Since the parse_args() stops parsing at '--', bootconfig_params()
will never get the '--' as param and initargs_found never be true.
In the result, if we pass some init arguments via the bootconfig,
those are always appended to the kernel command line with '--'
even if the kernel command line already has '--'.
To fix this correctly, check the return value of parse_args()
and set initargs_found true if the return value is not an error
but a valid address.
Link: https://lkml.kernel.org/r/159650953285.270383.14822353843556363851.stgit@devnote2
Fixes: f61872bb58 ("bootconfig: Use parse_args() to find bootconfig and '--'")
Cc: stable@vger.kernel.org
Reported-by: Arvind Sankar <nivedita@alum.mit.edu>
Suggested-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
- Introduce CONFIG_INIT_STACK_ALL_ZERO (Alexander Potapenko)
-----BEGIN PGP SIGNATURE-----
iQJKBAABCgA0FiEEpcP2jyKd1g9yPm4TiXL039xtwCYFAl8oXX4WHGtlZXNjb29r
QGNocm9taXVtLm9yZwAKCRCJcvTf3G3AJt/FD/wJISl6Va3UvJrwGWcjLqb3iQh/
38Nq7LV9ysUStpi5ibxhiB95uawFtAUsBLKyBKLtOERUz5RXiHrR9MI4UWNPBgNc
7/H5ZAkkD21LpzC76FH+a4SWQp1kQTiyu/iONn03LE8p4vSwSVZzoGqA1r4fpzGY
Np++2Ym/bzWV7R0Xdq/LI5oH9109dm75PhcCqCZPAtlIq+USXpyNAozimgREplVl
/clYmj7oruoRYiF5uheOlbpCEXYlybwVHfDKE2Uh5IcXcpm3OYZU9HEK5ot5oudJ
Z7bIcMeS2mMtSH/hhyjFbi0cZBVtJFc9exHRmuiDiYzNkWzaT2/5xAMUzw65q7Yk
BTpr5AU+nkVQwuAmkN3AyBLrqQYyhWL0+xnWRmbbjt2yoqCx5x3AyxaBgHDV4vgF
sTNhczFQdGqhlmvbxOw93PARV+lU9pozcc6b8TpXVdsE+bFFN5mBuRljIOTCRvke
yxFsLF9olfNB3CXTHXAWLC/RuqdH/Vk7zC0vS34tlmvWgVC07P9QXyWciqcldAgL
BsFXsRt6bRvOukyunhRfQkLVRxsOCLhQuYC33cRX9xY9vwCkM5v6TQH5WRcfxK7Q
swujqqvozYZ/njblBTeagg8sGg0OiqxpCvJZD6qA6s1mO3lG58CDqqwxd4DemIDF
/BxVarzUtmvBuiMBSQ==
=c2Rf
-----END PGP SIGNATURE-----
Merge tag 'var-init-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull automatic variable initialization updates from Kees Cook:
"This adds the "zero" init option from Clang, which is being used
widely in production builds of Android and Chrome OS (though it also
keeps the "pattern" init, which is better for debug builds).
- Introduce CONFIG_INIT_STACK_ALL_ZERO (Alexander Potapenko)"
* tag 'var-init-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
security: allow using Clang's zero initialization for stack variables
When booting on 32-bit machines (seen on OpenRISC) I saw this warning
with CONFIG_DEBUG_MUTEXES turned on.
------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at kernel/locking/mutex.c:1242 __mutex_unlock_slowpath+0x328/0x3ec
DEBUG_LOCKS_WARN_ON(__owner_task(owner) != current)
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 5.8.0-rc1-simple-smp-00005-g2864e2171db4-dirty #179
Call trace:
[<(ptrval)>] dump_stack+0x34/0x48
[<(ptrval)>] __warn+0x104/0x158
[<(ptrval)>] ? __mutex_unlock_slowpath+0x328/0x3ec
[<(ptrval)>] warn_slowpath_fmt+0x7c/0x94
[<(ptrval)>] __mutex_unlock_slowpath+0x328/0x3ec
[<(ptrval)>] mutex_unlock+0x18/0x28
[<(ptrval)>] __cpuhp_setup_state_cpuslocked.part.0+0x29c/0x2f4
[<(ptrval)>] ? page_alloc_cpu_dead+0x0/0x30
[<(ptrval)>] ? start_kernel+0x0/0x684
[<(ptrval)>] __cpuhp_setup_state+0x4c/0x5c
[<(ptrval)>] page_alloc_init+0x34/0x68
[<(ptrval)>] ? start_kernel+0x1a0/0x684
[<(ptrval)>] ? early_init_dt_scan_nodes+0x60/0x70
irq event stamp: 0
I traced this to kernel/locking/mutex.c storing 3 bits of MUTEX_FLAGS in
the task_struct pointer (mutex.owner). There is a comment saying that
task_structs are always aligned to L1_CACHE_BYTES. This is not true for
the init_task.
On 64-bit machines this is not a problem because symbol addresses are
naturally aligned to 64-bits providing 3 bits for MUTEX_FLAGS. Howerver,
for 32-bit machines the symbol address only has 2 bits available.
Fix this by setting init_task alignment to at least L1_CACHE_BYTES.
Signed-off-by: Stafford Horne <shorne@gmail.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=X7o0
-----END PGP SIGNATURE-----
Merge tag 'x86-cleanups-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cleanups from Ingo Molnar:
"Misc cleanups all around the place"
* tag 'x86-cleanups-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/ioperm: Initialize pointer bitmap with NULL rather than 0
x86: uv: uv_hub.h: Delete duplicated word
x86: cmpxchg_32.h: Delete duplicated word
x86: bootparam.h: Delete duplicated word
x86/mm: Remove the unused mk_kernel_pgd() #define
x86/tsc: Remove unused "US_SCALE" and "NS_SCALE" leftover macros
x86/ioapic: Remove unused "IOAPIC_AUTO" define
x86/mm: Drop unused MAX_PHYSADDR_BITS
x86/msr: Move the F15h MSRs where they belong
x86/idt: Make idt_descr static
initrd: Remove erroneous comment
x86/mm/32: Fix -Wmissing prototypes warnings for init.c
cpu/speculation: Add prototype for cpu_show_srbds()
x86/mm: Fix -Wmissing-prototypes warnings for arch/x86/mm/init.c
x86/asm: Unify __ASSEMBLY__ blocks
x86/cpufeatures: Mark two free bits in word 3
x86/msr: Lift AMD family 0x15 power-specific MSRs
kernel and initrd images.
ZSTD has a very fast decompressor, yet it compresses better than gzip.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=bARW
-----END PGP SIGNATURE-----
Merge tag 'x86-boot-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
"The main change in this cycle was to add support for ZSTD-compressed
kernel and initrd images.
ZSTD has a very fast decompressor, yet it compresses better than gzip"
* tag 'x86-boot-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Documentation: dontdiff: Add zstd compressed files
.gitignore: Add ZSTD-compressed files
x86: Add support for ZSTD compressed kernel
x86: Bump ZO_z_extra_bytes margin for zstd
usr: Add support for zstd compressed initramfs
init: Add support for zstd compressed kernel
lib: Add zstd support to decompress
lib: Prepare zstd for preboot environment, improve performance
- Add the zstd and zstd22 cmds to scripts/Makefile.lib
- Add the HAVE_KERNEL_ZSTD and KERNEL_ZSTD options
Architecture specific support is still needed for decompression.
Signed-off-by: Nick Terrell <terrelln@fb.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200730190841.2071656-4-nickrterrell@gmail.com
Add a simple helper to set timestamps with a kernel space file name and
switch the early init code over to it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add a simple helper to mknod with a kernel space file name and switch
the early init code over to it. Remove the now unused ksys_mknod.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add a simple helper to mkdir with a kernel space file name and switch
the early init code over to it. Remove the now unused ksys_mkdir.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add a simple helper to symlink with a kernel space file name and switch
the early init code over to it. Remove the now unused ksys_symlink.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add a simple helper to link with a kernel space file name and switch
the early init code over to it. Remove the now unused ksys_link.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add a simple helper to check if a file exists based on kernel space file
name and switch the early init code over to it. Note that this
theoretically changes behavior as it always is based on the effective
permissions. But during early init that doesn't make a difference.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add a simple helper to chroot with a kernel space file name and switch
the early init code over to it. Remove the now unused ksys_chroot.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add a simple helper to chdir with a kernel space file name and switch
the early init code over to it. Remove the now unused ksys_chdir.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add a simple helper to rmdir with a kernel space file name and switch
the early init code over to it. Remove the now unused ksys_rmdir.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add a simple helper to unlink with a kernel space file name and switch
the early init code over to it. Remove the now unused ksys_unlink.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Like ksys_umount, but takes a kernel pointer for the destination path.
Switch over the umount in the init code, which just happen to work due to
the implicit set_fs(KERNEL_DS) during early init right now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Like do_mount, but takes a kernel pointer for the destination path.
Switch over the mounts in the init code and devtmpfs to it, which
just happen to work due to the implicit set_fs(KERNEL_DS) during early
init right now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Set ramdisk_execute_command to "/init" at compile time. The command
line can still override it, but this saves a few instructions and
removes a NULL check.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Don't bother saving away the pathname and just use the new struct path
based utimes helper instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Don't rely on the implicit set_fs(KERNEL_DS) for ksys_open to work, but
instead open a struct file for /dev/console and then install it as FD
0/1/2 manually.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
There is no good reason to mess with file descriptors from in-kernel
code, switch the initramfs unpacking to struct file based write
instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
There is no point in trying to clean up after unpacking the initramfs
failed, as it should never get past the magic number check. In addition
the current code only removes file that are direct children of the root
entry, which wasn't complete anyway
Fixes: df52092f3c ("fastboot: remove duplicate unpack_to_rootfs()")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
If initrd support is not enable just print the warning directly instead
of hiding the fact that we just failed behind two stub functions.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
The classic initial ramdisk has been replaced by the much more
flexible and efficient initramfs a long time. Warn about it being
removed soon.
Includes a spelling fix from Colin Ian King <colin.king@canonical.com>.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
There is no good reason to mess with file descriptors from in-kernel
code, switch the initrd loading to struct file based read and writes
instead.
Also Pass an explicit offset instead of ->f_pos, and to make that easier,
use file scope file structs and offsets everywhere except for
identify_ramdisk_image instead of the current strange mix.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
BLKFLSBUF used to be overloaded for the ramdisk driver to free the whole
ramdisk, which was completely different behavior compared to all other
drivers. But this magic overload got removed in commit ff26956875
("brd: remove support for BLKFLSBUF"), so this call is entirely
pointless now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the special handling for multiple floppies in the initrd code.
No one should be using floppies for booting these days. (famous last
words..)
Includes a spelling fix from Colin Ian King <colin.king@canonical.com>.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
A sequence counter write side critical section must be protected by some
form of locking to serialize writers. A plain seqcount_t does not
contain the information of which lock must be held when entering a write
side critical section.
Use the new seqcount_spinlock_t data type, which allows to associate a
spinlock with the sequence counter. This enables lockdep to verify that
the spinlock used for writer serialization is held when the write side
critical section is entered.
If lockdep is disabled this lock association is compiled out and has
neither storage size nor runtime overhead.
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200720155530.1173732-14-a.darwish@linutronix.de
Qian reported that the current setup forgoes the Kconfig dependencies and
results in warnings such as:
WARNING: unmet direct dependencies detected for SCHED_THERMAL_PRESSURE
Depends on [n]: SMP [=y] && CPU_FREQ_THERMAL [=n]
Selected by [y]:
- ARM64 [=y]
Revert commit
e17ae7fea8 ("arm, arm64: Select CONFIG_SCHED_THERMAL_PRESSURE")
and re-implement it by making the option default to 'y' for arm64 and arm,
which respects Kconfig dependencies (i.e. will remain 'n' if
CPU_FREQ_THERMAL=n).
Fixes: e17ae7fea8 ("arm, arm64: Select CONFIG_SCHED_THERMAL_PRESSURE")
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200729135718.1871-1-valentin.schneider@arm.com
As Russell pointed out [1], this option is severely lacking in the
documentation department, and figuring out if one has the required
dependencies to benefit from turning it on is not straightforward.
Make it non user-visible, and add a bit of help to it. While at it, make it
depend on CPU_FREQ_THERMAL.
[1]: https://lkml.kernel.org/r/20200603173150.GB1551@shell.armlinux.org.uk
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200712165917.9168-3-valentin.schneider@arm.com
To allow the kernel not to play games with set_fs to call exec
implement kernel_execve. The function kernel_execve takes pointers
into kernel memory and copies the values pointed to onto the new
userspace stack.
The calls with arguments from kernel space of do_execve are replaced
with calls to kernel_execve.
The calls do_execve and do_execveat are made static as there are now
no callers outside of exec.
The comments that mention do_execve are updated to refer to
kernel_execve or execve depending on the circumstances. In addition
to correcting the comments, this makes it easy to grep for do_execve
and verify it is not used.
Inspired-by: https://lkml.kernel.org/r/20200627072704.2447163-1-hch@lst.de
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/87wo365ikj.fsf@x220.int.ebiederm.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Just like the NFS and CIFS root code this better lives with the
driver it is tightly integrated with.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
The only caller of the bstat function becomes cleaner and simpler when
open coding the function.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: NeilBrown <neilb@suse.de>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
A common question asked when debugging seccomp filters is "how many
filters are attached to your process?" Provide a way to easily answer
this question through /proc/$pid/status with a "Seccomp_filters" line.
Signed-off-by: Kees Cook <keescook@chromium.org>
scripts/cc-can-link.sh tests if the compiler can link userspace
programs.
When $(CC) is GCC, it is checked against the target architecture
because the toolchain prefix is specified as a part of $(CC).
When $(CC) is Clang, it is checked against the host architecture
because --target option is missing.
Pass $(CLANG_FLAGS) to scripts/cc-can-link.sh to evaluate the link
capability for the target architecture.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
The nommu-mmap.txt file provides description of user visible
behaviuour. So, move it to the admin-guide.
As it is already at the ReST, also rename it.
Suggested-by: Mike Rapoport <rppt@linux.ibm.com>
Suggested-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/3a63d1833b513700755c85bf3bda0a6c4ab56986.1592918949.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Most architectures have been passing the location of an initrd via the
initrd= option since their inception. Remove the comment as it's both
wrong and unrelated to the commit that introduced it.
For a bit more context, I assume there's been some confusion between
"initrd" being a keyword in things like extlinux.conf and also that for
quite a long time now initrd information is passed via device tree and
not the command line on relevant architectures. But it's still true that
it's been a valid command line option to the kernel since the 90s. It's
just the case that in 2018 the code was consolidated from under arch/
and in to this file.
[ bp: Move the context clarification up into the commit message proper. ]
Fixes: 694cfd87b0 ("x86/setup: Add an initrdmem= option to specify initrd physical address")
Signed-off-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200619143056.24538-1-trini@konsulko.com
In addition to -ftrivial-auto-var-init=pattern (used by
CONFIG_INIT_STACK_ALL now) Clang also supports zero initialization for
locals enabled by -ftrivial-auto-var-init=zero. The future of this flag
is still being debated (see https://bugs.llvm.org/show_bug.cgi?id=45497).
Right now it is guarded by another flag,
-enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang,
which means it may not be supported by future Clang releases. Another
possible resolution is that -ftrivial-auto-var-init=zero will persist
(as certain users have already started depending on it), but the name
of the guard flag will change.
In the meantime, zero initialization has proven itself as a good
production mitigation measure against uninitialized locals. Unlike pattern
initialization, which has a higher chance of triggering existing bugs,
zero initialization provides safe defaults for strings, pointers, indexes,
and sizes. On the other hand, pattern initialization remains safer for
return values. Chrome OS and Android are moving to using zero
initialization for production builds.
Performance-wise, the difference between pattern and zero initialization
is usually negligible, although the generated code for zero
initialization is more compact.
This patch renames CONFIG_INIT_STACK_ALL to CONFIG_INIT_STACK_ALL_PATTERN
and introduces another config option, CONFIG_INIT_STACK_ALL_ZERO, that
enables zero initialization for locals if the corresponding flags are
supported by Clang.
Cc: Kees Cook <keescook@chromium.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Alexander Potapenko <glider@google.com>
Link: https://lore.kernel.org/r/20200616083435.223038-1-glider@google.com
Reviewed-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
- fix build rules in binderfs sample
- fix build errors when Kbuild recurses to the top Makefile
- covert '---help---' in Kconfig to 'help'
-----BEGIN PGP SIGNATURE-----
iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl7lBuYVHG1hc2FoaXJv
eUBrZXJuZWwub3JnAAoJED2LAQed4NsGHvIP/3iErjPshpg/phwH8NTCS4SFkiti
BZRM+2lupSn7Qs53BTpVzIkXoHBJQZlJxlQ5HY8ScO+fiz28rKZr+b40us+je1Q+
SkvSPfwZzxjEg7lAZutznG4KgItJLWJKmDyh9T8Y8TAuG4f8WO0hKnXoAp3YorS2
zppEIxso8O5spZPjp+fF/fPbxPjIsabGK7Jp2LpSVFR5pVDHI/ycTlKQS+MFpMEx
6JIpdFRw7TkvKew1dr5uAWT5btWHatEqjSR3JeyVHv3EICTGQwHmcHK67cJzGInK
T51+DT7/CpKtmRgGMiTEu/INfMzzoQAKl6Fcu+vMaShTN97Hk9DpdtQyvA6P/h3L
8GA4UBct05J7fjjIB7iUD+GYQ0EZbaFujzRXLYk+dQqEJRbhcCwvdzggGp0WvGRs
1f8/AIpgnQv8JSL/bOMgGMS5uL2dSLsgbzTdr6RzWf1jlYdI1i4u7AZ/nBrwWP+Z
iOBkKsVceEoJrTbaynl3eoYqFLtWyDau+//oBc2gUvmhn8ioM5dfqBRiJjxJnPG9
/giRj6xRIqMMEw8Gg8PCG7WebfWxWyaIQwlWBbPok7DwISURK5mvOyakZL+Q25/y
6MBr2H8NEJsf35q0GTINpfZnot7NX4JXrrndJH8NIRC7HEhwd29S041xlQJdP0rs
E76xsOr3hrAmBu4P
=1NIT
-----END PGP SIGNATURE-----
Merge tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull more Kbuild updates from Masahiro Yamada:
- fix build rules in binderfs sample
- fix build errors when Kbuild recurses to the top Makefile
- covert '---help---' in Kconfig to 'help'
* tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
treewide: replace '---help---' in Kconfig files with 'help'
kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables
samples: binderfs: really compile this sample and fix build issues
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.
This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.
There are a variety of indentation styles found.
a) 4 spaces + '---help---'
b) 7 spaces + '---help---'
c) 8 spaces + '---help---'
d) 1 space + 1 tab + '---help---'
e) 1 tab + '---help---' (correct indentation)
f) 1 tab + 1 space + '---help---'
g) 1 tab + 2 spaces + '---help---'
In order to convert all of them to 1 tab + 'help', I ran the
following commend:
$ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
-----BEGIN PGP SIGNATURE-----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=YTGf
-----END PGP SIGNATURE-----
Merge tag 'notifications-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull notification queue from David Howells:
"This adds a general notification queue concept and adds an event
source for keys/keyrings, such as linking and unlinking keys and
changing their attributes.
Thanks to Debarshi Ray, we do have a pull request to use this to fix a
problem with gnome-online-accounts - as mentioned last time:
https://gitlab.gnome.org/GNOME/gnome-online-accounts/merge_requests/47
Without this, g-o-a has to constantly poll a keyring-based kerberos
cache to find out if kinit has changed anything.
[ There are other notification pending: mount/sb fsinfo notifications
for libmount that Karel Zak and Ian Kent have been working on, and
Christian Brauner would like to use them in lxc, but let's see how
this one works first ]
LSM hooks are included:
- A set of hooks are provided that allow an LSM to rule on whether or
not a watch may be set. Each of these hooks takes a different
"watched object" parameter, so they're not really shareable. The
LSM should use current's credentials. [Wanted by SELinux & Smack]
- A hook is provided to allow an LSM to rule on whether or not a
particular message may be posted to a particular queue. This is
given the credentials from the event generator (which may be the
system) and the watch setter. [Wanted by Smack]
I've provided SELinux and Smack with implementations of some of these
hooks.
WHY
===
Key/keyring notifications are desirable because if you have your
kerberos tickets in a file/directory, your Gnome desktop will monitor
that using something like fanotify and tell you if your credentials
cache changes.
However, we also have the ability to cache your kerberos tickets in
the session, user or persistent keyring so that it isn't left around
on disk across a reboot or logout. Keyrings, however, cannot currently
be monitored asynchronously, so the desktop has to poll for it - not
so good on a laptop. This facility will allow the desktop to avoid the
need to poll.
DESIGN DECISIONS
================
- The notification queue is built on top of a standard pipe. Messages
are effectively spliced in. The pipe is opened with a special flag:
pipe2(fds, O_NOTIFICATION_PIPE);
The special flag has the same value as O_EXCL (which doesn't seem
like it will ever be applicable in this context)[?]. It is given up
front to make it a lot easier to prohibit splice&co from accessing
the pipe.
[?] Should this be done some other way? I'd rather not use up a new
O_* flag if I can avoid it - should I add a pipe3() system call
instead?
The pipe is then configured::
ioctl(fds[1], IOC_WATCH_QUEUE_SET_SIZE, queue_depth);
ioctl(fds[1], IOC_WATCH_QUEUE_SET_FILTER, &filter);
Messages are then read out of the pipe using read().
- It should be possible to allow write() to insert data into the
notification pipes too, but this is currently disabled as the
kernel has to be able to insert messages into the pipe *without*
holding pipe->mutex and the code to make this work needs careful
auditing.
- sendfile(), splice() and vmsplice() are disabled on notification
pipes because of the pipe->mutex issue and also because they
sometimes want to revert what they just did - but one or more
notification messages might've been interleaved in the ring.
- The kernel inserts messages with the wait queue spinlock held. This
means that pipe_read() and pipe_write() have to take the spinlock
to update the queue pointers.
- Records in the buffer are binary, typed and have a length so that
they can be of varying size.
This allows multiple heterogeneous sources to share a common
buffer; there are 16 million types available, of which I've used
just a few, so there is scope for others to be used. Tags may be
specified when a watchpoint is created to help distinguish the
sources.
- Records are filterable as types have up to 256 subtypes that can be
individually filtered. Other filtration is also available.
- Notification pipes don't interfere with each other; each may be
bound to a different set of watches. Any particular notification
will be copied to all the queues that are currently watching for it
- and only those that are watching for it.
- When recording a notification, the kernel will not sleep, but will
rather mark a queue as having lost a message if there's
insufficient space. read() will fabricate a loss notification
message at an appropriate point later.
- The notification pipe is created and then watchpoints are attached
to it, using one of:
keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fds[1], 0x01);
watch_mount(AT_FDCWD, "/", 0, fd, 0x02);
watch_sb(AT_FDCWD, "/mnt", 0, fd, 0x03);
where in both cases, fd indicates the queue and the number after is
a tag between 0 and 255.
- Watches are removed if either the notification pipe is destroyed or
the watched object is destroyed. In the latter case, a message will
be generated indicating the enforced watch removal.
Things I want to avoid:
- Introducing features that make the core VFS dependent on the
network stack or networking namespaces (ie. usage of netlink).
- Dumping all this stuff into dmesg and having a daemon that sits
there parsing the output and distributing it as this then puts the
responsibility for security into userspace and makes handling
namespaces tricky. Further, dmesg might not exist or might be
inaccessible inside a container.
- Letting users see events they shouldn't be able to see.
TESTING AND MANPAGES
====================
- The keyutils tree has a pipe-watch branch that has keyctl commands
for making use of notifications. Proposed manual pages can also be
found on this branch, though a couple of them really need to go to
the main manpages repository instead.
If the kernel supports the watching of keys, then running "make
test" on that branch will cause the testing infrastructure to spawn
a monitoring process on the side that monitors a notifications pipe
for all the key/keyring changes induced by the tests and they'll
all be checked off to make sure they happened.
https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/keyutils.git/log/?h=pipe-watch
- A test program is provided (samples/watch_queue/watch_test) that
can be used to monitor for keyrings, mount and superblock events.
Information on the notifications is simply logged to stdout"
* tag 'notifications-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
smack: Implement the watch_key and post_notification hooks
selinux: Implement the watch_key security hook
keys: Make the KEY_NEED_* perms an enum rather than a mask
pipe: Add notification lossage handling
pipe: Allow buffers to be marked read-whole-or-error for notifications
Add sample notification program
watch_queue: Add a key/keyring notification facility
security: Add hooks to rule on setting a watch
pipe: Add general notification queue support
pipe: Add O_NOTIFICATION_PIPE
security: Add a hook for the point of notification insertion
uapi: General notification queue definitions
Merge the state of the locking kcsan branch before the read/write_once()
and the atomics modifications got merged.
Squash the fallout of the rebase on top of the read/write once and atomic
fallback work into the merge. The history of the original branch is
preserved in tag locking-kcsan-2020-06-02.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Pull READ/WRITE_ONCE rework from Will Deacon:
"This the READ_ONCE rework I've been working on for a while, which
bumps the minimum GCC version and improves code-gen on arm64 when
stack protector is enabled"
[ Side note: I'm _really_ tempted to raise the minimum gcc version to
4.9, so that we can just say that we require _Generic() support.
That would allow us to more cleanly handle a lot of the cases where we
depend on very complex macros with 'sizeof' or __builtin_choose_expr()
with __builtin_types_compatible_p() etc.
This branch has a workaround for sparse not handling _Generic(),
either, but that was already fixed in the sparse development branch,
so it's really just gcc-4.9 that we'd require. - Linus ]
* 'rwonce/rework' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux:
compiler_types.h: Use unoptimized __unqual_scalar_typeof for sparse
compiler_types.h: Optimize __unqual_scalar_typeof compilation time
compiler.h: Enforce that READ_ONCE_NOCHECK() access size is sizeof(long)
compiler-types.h: Include naked type in __pick_integer_type() match
READ_ONCE: Fix comment describing 2x32-bit atomicity
gcov: Remove old GCC 3.4 support
arm64: barrier: Use '__unqual_scalar_typeof' for acquire/release macros
locking/barriers: Use '__unqual_scalar_typeof' for load-acquire macros
READ_ONCE: Drop pointer qualifiers when reading from scalar types
READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses
READ_ONCE: Simplify implementations of {READ,WRITE}_ONCE()
arm64: csum: Disable KASAN for do_csum()
fault_inject: Don't rely on "return value" from WRITE_ONCE()
net: tls: Avoid assigning 'const' pointer to non-const pointer
netfilter: Avoid assigning 'const' pointer to non-const pointer
compiler/gcc: Raise minimum GCC version for kernel builds to 4.8
Patch series "mm: consolidate definitions of page table accessors", v2.
The low level page table accessors (pXY_index(), pXY_offset()) are
duplicated across all architectures and sometimes more than once. For
instance, we have 31 definition of pgd_offset() for 25 supported
architectures.
Most of these definitions are actually identical and typically it boils
down to, e.g.
static inline unsigned long pmd_index(unsigned long address)
{
return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1);
}
static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
{
return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address);
}
These definitions can be shared among 90% of the arches provided
XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined.
For architectures that really need a custom version there is always
possibility to override the generic version with the usual ifdefs magic.
These patches introduce include/linux/pgtable.h that replaces
include/asm-generic/pgtable.h and add the definitions of the page table
accessors to the new header.
This patch (of 12):
The linux/mm.h header includes <asm/pgtable.h> to allow inlining of the
functions involving page table manipulations, e.g. pte_alloc() and
pmd_alloc(). So, there is no point to explicitly include <asm/pgtable.h>
in the files that include <linux/mm.h>.
The include statements in such cases are remove with a simple loop:
for f in $(git grep -l "include <linux/mm.h>") ; do
sed -i -e '/include <asm\/pgtable.h>/ d' $f
done
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org
Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "support setting sysctl parameters from kernel command line", v3.
This series adds support for something that seems like many people
always wanted but nobody added it yet, so here's the ability to set
sysctl parameters via kernel command line options in the form of
sysctl.vm.something=1
The important part is Patch 1. The second, not so important part is an
attempt to clean up legacy one-off parameters that do the same thing as
a sysctl. I don't want to remove them completely for compatibility
reasons, but with generic sysctl support the idea is to remove the
one-off param handlers and treat the parameters as aliases for the
sysctl variants.
I have identified several parameters that mention sysctl counterparts in
Documentation/admin-guide/kernel-parameters.txt but there might be more.
The conversion also has varying level of success:
- numa_zonelist_order is converted in Patch 2 together with adding the
necessary infrastructure. It's easy as it doesn't really do anything
but warn on deprecated value these days.
- hung_task_panic is converted in Patch 3, but there's a downside that
now it only accepts 0 and 1, while previously it was any integer
value
- nmi_watchdog maps to two sysctls nmi_watchdog and hardlockup_panic,
so there's no straighforward conversion possible
- traceoff_on_warning is a flag without value and it would be required
to handle that somehow in the conversion infractructure, which seems
pointless for a single flag
This patch (of 5):
A recently proposed patch to add vm_swappiness command line parameter in
addition to existing sysctl [1] made me wonder why we don't have a
general support for passing sysctl parameters via command line.
Googling found only somebody else wondering the same [2], but I haven't
found any prior discussion with reasons why not to do this.
Settings the vm_swappiness issue aside (the underlying issue might be
solved in a different way), quick search of kernel-parameters.txt shows
there are already some that exist as both sysctl and kernel parameter -
hung_task_panic, nmi_watchdog, numa_zonelist_order, traceoff_on_warning.
A general mechanism would remove the need to add more of those one-offs
and might be handy in situations where configuration by e.g.
/etc/sysctl.d/ is impractical.
Hence, this patch adds a new parse_args() pass that looks for parameters
prefixed by 'sysctl.' and tries to interpret them as writes to the
corresponding sys/ files using an temporary in-kernel procfs mount.
This mechanism was suggested by Eric W. Biederman [3], as it handles
all dynamically registered sysctl tables, even though we don't handle
modular sysctls. Errors due to e.g. invalid parameter name or value
are reported in the kernel log.
The processing is hooked right before the init process is loaded, as
some handlers might be more complicated than simple setters and might
need some subsystems to be initialized. At the moment the init process
can be started and eventually execute a process writing to /proc/sys/
then it should be also fine to do that from the kernel.
Sysctls registered later on module load time are not set by this
mechanism - it's expected that in such scenarios, setting sysctl values
from userspace is practical enough.
[1] https://lore.kernel.org/r/BL0PR02MB560167492CA4094C91589930E9FC0@BL0PR02MB5601.namprd02.prod.outlook.com/
[2] https://unix.stackexchange.com/questions/558802/how-to-set-sysctl-using-kernel-command-line-parameter
[3] https://lore.kernel.org/r/87bloj2skm.fsf@x220.int.ebiederm.org/
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Ivan Teterevkov <ivan.teterevkov@nutanix.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: "Guilherme G . Piccoli" <gpiccoli@canonical.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Link: http://lkml.kernel.org/r/20200427180433.7029-1-vbabka@suse.cz
Link: http://lkml.kernel.org/r/20200427180433.7029-2-vbabka@suse.cz
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- fix warnings in 'make clean' for ARCH=um, hexagon, h8300, unicore32
- ensure to rebuild all objects when the compiler is upgraded
- exclude system headers from dependency tracking and fixdep processing
- fix potential bit-size mismatch between the kernel and BPF user-mode
helper
- add the new syntax 'userprogs' to build user-space programs for the
target architecture (the same arch as the kernel)
- compile user-space sample code under samples/ for the target arch
instead of the host arch
- make headers_install fail if a CONFIG option is leaked to user-space
- sanitize the output format of scripts/checkstack.pl
- handle ARM 'push' instruction in scripts/checkstack.pl
- error out before modpost if a module name conflict is found
- error out when multiple directories are passed to M= because this
feature is broken for a long time
- add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info
- a lot of cleanups of modpost
- dump vmlinux symbols out into vmlinux.symvers, and reuse it in the
second pass of modpost
- do not run the second pass of modpost if nothing in modules is updated
- install modules.builtin(.modinfo) by 'make install' as well as by
'make modules_install' because it is useful even when CONFIG_MODULES=n
- add new command line variables, GZIP, BZIP2, LZOP, LZMA, LZ4, and XZ
to allow users to use alternatives such as pigz, pbzip2, etc.
-----BEGIN PGP SIGNATURE-----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=GKe5
-----END PGP SIGNATURE-----
Merge tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- fix warnings in 'make clean' for ARCH=um, hexagon, h8300, unicore32
- ensure to rebuild all objects when the compiler is upgraded
- exclude system headers from dependency tracking and fixdep processing
- fix potential bit-size mismatch between the kernel and BPF user-mode
helper
- add the new syntax 'userprogs' to build user-space programs for the
target architecture (the same arch as the kernel)
- compile user-space sample code under samples/ for the target arch
instead of the host arch
- make headers_install fail if a CONFIG option is leaked to user-space
- sanitize the output format of scripts/checkstack.pl
- handle ARM 'push' instruction in scripts/checkstack.pl
- error out before modpost if a module name conflict is found
- error out when multiple directories are passed to M= because this
feature is broken for a long time
- add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info
- a lot of cleanups of modpost
- dump vmlinux symbols out into vmlinux.symvers, and reuse it in the
second pass of modpost
- do not run the second pass of modpost if nothing in modules is
updated
- install modules.builtin(.modinfo) by 'make install' as well as by
'make modules_install' because it is useful even when
CONFIG_MODULES=n
- add new command line variables, GZIP, BZIP2, LZOP, LZMA, LZ4, and XZ
to allow users to use alternatives such as pigz, pbzip2, etc.
* tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (96 commits)
kbuild: add variables for compression tools
Makefile: install modules.builtin even if CONFIG_MODULES=n
mksysmap: Fix the mismatch of '.L' symbols in System.map
kbuild: doc: rename LDFLAGS to KBUILD_LDFLAGS
modpost: change elf_info->size to size_t
modpost: remove is_vmlinux() helper
modpost: strip .o from modname before calling new_module()
modpost: set have_vmlinux in new_module()
modpost: remove mod->skip struct member
modpost: add mod->is_vmlinux struct member
modpost: remove is_vmlinux() call in check_for_{gpl_usage,unused}()
modpost: remove mod->is_dot_o struct member
modpost: move -d option in scripts/Makefile.modpost
modpost: remove -s option
modpost: remove get_next_text() and make {grab,release_}file static
modpost: use read_text_file() and get_line() for reading text files
modpost: avoid false-positive file open error
modpost: fix potential mmap'ed file overrun in get_src_version()
modpost: add read_text_file() and get_line() helpers
modpost: do not call get_modinfo() for vmlinux(.o)
...
This allows C code to make use of compilers with support for output
variables along the fallthrough path via preprocessor define:
CONFIG_CC_HAS_ASM_GOTO_OUTPUT
[ This is not used anywhere yet, and currently released compilers don't
support this yet, but it's coming, and I have some local experimental
patches to take advantage of it when it does - Linus ]
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some init systems (eg. systemd) have init at their own paths, for
example, /usr/lib/systemd/systemd. A compatibility symlink to one of the
hardcoded init paths is provided by another package, usually named
something like systemd-sysvcompat or similar.
Currently distro maintainers who are hands-off on the bootloader are more
or less required to include those compatibility links as part of their
base distribution, because it's hard to migrate away from them since
there's a risk some users will not get the message to set init= on the
kernel command line appropriately.
Moreover, for distributions where the init system is something the
distribution itself is opinionated about (eg. Arch, which has systemd in
the required `base` package), we could usually reasonably configure this
ahead of time when building the distribution kernel. However, we
currently simply don't have any way to configure the kernel to do this.
Here's an example discussion where removing sysvcompat was discussed by
distro maintainers[0].
This patch adds a new Kconfig tunable, CONFIG_DEFAULT_INIT, which if set
is tried before the hardcoded fallback list. So the order of precedence
is now thus:
1. init= on command line (on failure: panic)
2. CONFIG_DEFAULT_INIT (on failure: try #3)
3. Hardcoded fallback list (on failure: panic)
This new config parameter will allow distribution maintainers to move away
from these compatibility links safely, without having to worry that their
users might not have the right init=.
There are also two other benefits of this over having the distribution
maintain a symlink:
1. One of the value propositions over simply having distributions
maintain a /sbin/init symlink via a package is that it also frees
distributions which have a preferred default, but not mandatory, init
system from having their package manager fight with their users for
control of /{s,}bin/init. Instead, the distribution simply makes
their preference known in CONFIG_DEFAULT_INIT, and if the user
installs another init system and uninstalls the default one they can
still make use of /{s,}bin/init and friends for their own uses. This
makes more cases Just Work(tm) without the user having to perform
extra configuration via init=.
2. Since before this we don't know which path the distribution actually
_intends_ to serve init from, we don't pr_err if it is simply
missing, and usually will just silently put the user in a /bin/sh
shell. Now that the distribution can make a declaration of intent, we
can be more vocal when this init system fails to launch for any
reason, even if it's simply because no file exists at that location,
speeding up the palaver of init/mount dependency/etc debugging a bit.
[0]: https://lists.archlinux.org/pipermail/arch-dev-public/2019-January/029435.html
Signed-off-by: Chris Down <chris@chrisdown.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: http://lkml.kernel.org/r/20200522160234.GA1487022@chrisdown.name
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge more updates from Andrew Morton:
"More mm/ work, plenty more to come
Subsystems affected by this patch series: slub, memcg, gup, kasan,
pagealloc, hugetlb, vmscan, tools, mempolicy, memblock, hugetlbfs,
thp, mmap, kconfig"
* akpm: (131 commits)
arm64: mm: use ARCH_HAS_DEBUG_WX instead of arch defined
x86: mm: use ARCH_HAS_DEBUG_WX instead of arch defined
riscv: support DEBUG_WX
mm: add DEBUG_WX support
drivers/base/memory.c: cache memory blocks in xarray to accelerate lookup
mm/thp: rename pmd_mknotpresent() as pmd_mkinvalid()
powerpc/mm: drop platform defined pmd_mknotpresent()
mm: thp: don't need to drain lru cache when splitting and mlocking THP
hugetlbfs: get unmapped area below TASK_UNMAPPED_BASE for hugetlbfs
sparc32: register memory occupied by kernel as memblock.memory
include/linux/memblock.h: fix minor typo and unclear comment
mm, mempolicy: fix up gup usage in lookup_node
tools/vm/page_owner_sort.c: filter out unneeded line
mm: swap: memcg: fix memcg stats for huge pages
mm: swap: fix vmstats for huge pages
mm: vmscan: limit the range of LRU type balancing
mm: vmscan: reclaim writepage is IO cost
mm: vmscan: determine anon/file pressure balance at the reclaim root
mm: balance LRU lists based on relative thrashing
mm: only count actual rotations as LRU reclaim cost
...
Without swap page tracking, users that are otherwise memory controlled can
easily escape their containment and allocate significant amounts of memory
that they're not being charged for. That's because swap does readahead,
but without the cgroup records of who owned the page at swapout, readahead
pages don't get charged until somebody actually faults them into their
page table and we can identify an owner task. This can be maliciously
exploited with MADV_WILLNEED, which triggers arbitrary readahead
allocations without charging the pages.
Make swap swap page tracking an integral part of memcg and remove the
Kconfig options. In the first place, it was only made configurable to
allow users to save some memory. But the overhead of tracking cgroup
ownership per swap page is minimal - 2 byte per page, or 512k per 1G of
swap, or 0.04%. Saving that at the expense of broken containment
semantics is not something we should present as a coequal option.
The swapaccount=0 boot option will continue to exist, and it will
eliminate the page_counter overhead and hide the swap control files, but
it won't disable swap slot ownership tracking.
This patch makes sure we always have the cgroup records at swapin time;
the next patch will fix the actual bug by charging readahead swap pages at
swapin time rather than at fault time.
v2: fix double swap charge bug in cgroup1/cgroup2 code gating
[hannes@cmpxchg.org: fix crash with cgroup_disable=memory]
Link: http://lkml.kernel.org/r/20200521215855.GB815153@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Link: http://lkml.kernel.org/r/20200508183105.225460-16-hannes@cmpxchg.org
Debugged-by: Hugh Dickins <hughd@google.com>
Debugged-by: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
padata will soon initialize the system's struct pages in parallel, so it
needs to be ready by page_alloc_init_late().
The error return from padata_driver_init() triggers an initcall warning,
so add a warning to padata_init() to avoid silent failure.
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Josh Triplett <josh@joshtriplett.org>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Robert Elliott <elliott@hpe.com>
Cc: Shile Zhang <shile.zhang@linux.alibaba.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Link: http://lkml.kernel.org/r/20200527173608.2885243-3-daniel.m.jordan@oracle.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- added support for MIPSr5 and P5600 cores
- converted Loongson PCI driver into a PCI host driver using the generic
PCI framework
- added emulation of CPUCFG command for Loogonson64 cpus
- removed of LASAT, PMC MSP71xx and NEC MARKEINS/EMMA
- ioremap cleanup
- fix for a race between two threads faulting the same page
- various cleanups and fixes
-----BEGIN PGP SIGNATURE-----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=eAtN
-----END PGP SIGNATURE-----
Merge tag 'mips_5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux
Pull MIPS updates from Thomas Bogendoerfer:
- added support for MIPSr5 and P5600 cores
- converted Loongson PCI driver into a PCI host driver using the
generic PCI framework
- added emulation of CPUCFG command for Loogonson64 cpus
- removed of LASAT, PMC MSP71xx and NEC MARKEINS/EMMA
- ioremap cleanup
- fix for a race between two threads faulting the same page
- various cleanups and fixes
* tag 'mips_5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (143 commits)
MIPS: ralink: drop ralink_clk_init for mt7621
MIPS: ralink: bootrom: mark a function as __init to save some memory
MIPS: Loongson64: Reorder CPUCFG model match arms
MIPS: Expose Loongson CPUCFG availability via HWCAP
MIPS: Loongson64: Guard against future cores without CPUCFG
MIPS: Fix build warning about "PTR_STR" redefinition
MIPS: Loongson64: Remove not used pci.c
MIPS: Loongson64: Define PCI_IOBASE
MIPS: CPU_LOONGSON2EF need software to maintain cache consistency
MIPS: DTS: Fix build errors used with various configs
MIPS: Loongson64: select NO_EXCEPT_FILL
MIPS: Fix IRQ tracing when call handle_fpe() and handle_msa_fpe()
MIPS: mm: add page valid judgement in function pte_modify
mm/memory.c: Add memory read privilege on page fault handling
mm/memory.c: Update local TLB if PTE entry exists
MIPS: Do not flush tlb page when updating PTE entry
MIPS: ingenic: Default to a generic board
MIPS: ingenic: Add support for GCW Zero prototype
MIPS: ingenic: DTS: Add memory info of GCW Zero
MIPS: Loongson64: Switch to generic PCI driver
...
- Branch Target Identification (BTI)
* Support for ARMv8.5-BTI in both user- and kernel-space. This
allows branch targets to limit the types of branch from which
they can be called and additionally prevents branching to
arbitrary code, although kernel support requires a very recent
toolchain.
* Function annotation via SYM_FUNC_START() so that assembly
functions are wrapped with the relevant "landing pad"
instructions.
* BPF and vDSO updates to use the new instructions.
* Addition of a new HWCAP and exposure of BTI capability to
userspace via ID register emulation, along with ELF loader
support for the BTI feature in .note.gnu.property.
* Non-critical fixes to CFI unwind annotations in the sigreturn
trampoline.
- Shadow Call Stack (SCS)
* Support for Clang's Shadow Call Stack feature, which reserves
platform register x18 to point at a separate stack for each
task that holds only return addresses. This protects function
return control flow from buffer overruns on the main stack.
* Save/restore of x18 across problematic boundaries (user-mode,
hypervisor, EFI, suspend, etc).
* Core support for SCS, should other architectures want to use it
too.
* SCS overflow checking on context-switch as part of the existing
stack limit check if CONFIG_SCHED_STACK_END_CHECK=y.
- CPU feature detection
* Removed numerous "SANITY CHECK" errors when running on a system
with mismatched AArch32 support at EL1. This is primarily a
concern for KVM, which disabled support for 32-bit guests on
such a system.
* Addition of new ID registers and fields as the architecture has
been extended.
- Perf and PMU drivers
* Minor fixes and cleanups to system PMU drivers.
- Hardware errata
* Unify KVM workarounds for VHE and nVHE configurations.
* Sort vendor errata entries in Kconfig.
- Secure Monitor Call Calling Convention (SMCCC)
* Update to the latest specification from Arm (v1.2).
* Allow PSCI code to query the SMCCC version.
- Software Delegated Exception Interface (SDEI)
* Unexport a bunch of unused symbols.
* Minor fixes to handling of firmware data.
- Pointer authentication
* Add support for dumping the kernel PAC mask in vmcoreinfo so
that the stack can be unwound by tools such as kdump.
* Simplification of key initialisation during CPU bringup.
- BPF backend
* Improve immediate generation for logical and add/sub
instructions.
- vDSO
- Minor fixes to the linker flags for consistency with other
architectures and support for LLVM's unwinder.
- Clean up logic to initialise and map the vDSO into userspace.
- ACPI
- Work around for an ambiguity in the IORT specification relating
to the "num_ids" field.
- Support _DMA method for all named components rather than only
PCIe root complexes.
- Minor other IORT-related fixes.
- Miscellaneous
* Initialise debug traps early for KGDB and fix KDB cacheflushing
deadlock.
* Minor tweaks to early boot state (documentation update, set
TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections).
* Refactoring and cleanup
-----BEGIN PGP SIGNATURE-----
iQFEBAABCgAuFiEEPxTL6PPUbjXGY88ct6xw3ITBYzQFAl7U9csQHHdpbGxAa2Vy
bmVsLm9yZwAKCRC3rHDchMFjNLBHCACs/YU4SM7Om5f+7QnxIKao5DBr2CnGGvdC
yTfDghFDTLQVv3MufLlfno3yBe5G8sQpcZfcc+hewfcGoMzVZXu8s7LzH6VSn9T9
jmT3KjDMrg0RjSHzyumJp2McyelTk0a4FiKArSIIKsJSXUyb1uPSgm7SvKVDwEwU
JGDzL9IGilmq59GiXfDzGhTZgmC37QdwRoRxDuqtqWQe5CHoRXYexg87HwBKOQxx
HgU9L7ehri4MRZfpyjaDrr6quJo3TVnAAKXNBh3mZAskVS9ZrfKpEH0kYWYuqybv
znKyHRecl/rrGePV8RTMtrwnSdU26zMXE/omsVVauDfG9hqzqm+Q
=w3qi
-----END PGP SIGNATURE-----
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"A sizeable pile of arm64 updates for 5.8.
Summary below, but the big two features are support for Branch Target
Identification and Clang's Shadow Call stack. The latter is currently
arm64-only, but the high-level parts are all in core code so it could
easily be adopted by other architectures pending toolchain support
Branch Target Identification (BTI):
- Support for ARMv8.5-BTI in both user- and kernel-space. This allows
branch targets to limit the types of branch from which they can be
called and additionally prevents branching to arbitrary code,
although kernel support requires a very recent toolchain.
- Function annotation via SYM_FUNC_START() so that assembly functions
are wrapped with the relevant "landing pad" instructions.
- BPF and vDSO updates to use the new instructions.
- Addition of a new HWCAP and exposure of BTI capability to userspace
via ID register emulation, along with ELF loader support for the
BTI feature in .note.gnu.property.
- Non-critical fixes to CFI unwind annotations in the sigreturn
trampoline.
Shadow Call Stack (SCS):
- Support for Clang's Shadow Call Stack feature, which reserves
platform register x18 to point at a separate stack for each task
that holds only return addresses. This protects function return
control flow from buffer overruns on the main stack.
- Save/restore of x18 across problematic boundaries (user-mode,
hypervisor, EFI, suspend, etc).
- Core support for SCS, should other architectures want to use it
too.
- SCS overflow checking on context-switch as part of the existing
stack limit check if CONFIG_SCHED_STACK_END_CHECK=y.
CPU feature detection:
- Removed numerous "SANITY CHECK" errors when running on a system
with mismatched AArch32 support at EL1. This is primarily a concern
for KVM, which disabled support for 32-bit guests on such a system.
- Addition of new ID registers and fields as the architecture has
been extended.
Perf and PMU drivers:
- Minor fixes and cleanups to system PMU drivers.
Hardware errata:
- Unify KVM workarounds for VHE and nVHE configurations.
- Sort vendor errata entries in Kconfig.
Secure Monitor Call Calling Convention (SMCCC):
- Update to the latest specification from Arm (v1.2).
- Allow PSCI code to query the SMCCC version.
Software Delegated Exception Interface (SDEI):
- Unexport a bunch of unused symbols.
- Minor fixes to handling of firmware data.
Pointer authentication:
- Add support for dumping the kernel PAC mask in vmcoreinfo so that
the stack can be unwound by tools such as kdump.
- Simplification of key initialisation during CPU bringup.
BPF backend:
- Improve immediate generation for logical and add/sub instructions.
vDSO:
- Minor fixes to the linker flags for consistency with other
architectures and support for LLVM's unwinder.
- Clean up logic to initialise and map the vDSO into userspace.
ACPI:
- Work around for an ambiguity in the IORT specification relating to
the "num_ids" field.
- Support _DMA method for all named components rather than only PCIe
root complexes.
- Minor other IORT-related fixes.
Miscellaneous:
- Initialise debug traps early for KGDB and fix KDB cacheflushing
deadlock.
- Minor tweaks to early boot state (documentation update, set
TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections).
- Refactoring and cleanup"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (148 commits)
KVM: arm64: Move __load_guest_stage2 to kvm_mmu.h
KVM: arm64: Check advertised Stage-2 page size capability
arm64/cpufeature: Add get_arm64_ftr_reg_nowarn()
ACPI/IORT: Remove the unused __get_pci_rid()
arm64/cpuinfo: Add ID_MMFR4_EL1 into the cpuinfo_arm64 context
arm64/cpufeature: Add remaining feature bits in ID_AA64PFR1 register
arm64/cpufeature: Add remaining feature bits in ID_AA64PFR0 register
arm64/cpufeature: Add remaining feature bits in ID_AA64ISAR0 register
arm64/cpufeature: Add remaining feature bits in ID_MMFR4 register
arm64/cpufeature: Add remaining feature bits in ID_PFR0 register
arm64/cpufeature: Introduce ID_MMFR5 CPU register
arm64/cpufeature: Introduce ID_DFR1 CPU register
arm64/cpufeature: Introduce ID_PFR2 CPU register
arm64/cpufeature: Make doublelock a signed feature in ID_AA64DFR0
arm64/cpufeature: Drop TraceFilt feature exposure from ID_DFR0 register
arm64/cpufeature: Add explicit ftr_id_isar0[] for ID_ISAR0 register
arm64: mm: Add asid_gen_match() helper
firmware: smccc: Fix missing prototype warning for arm_smccc_version_init
arm64: vdso: Fix CFI directives in sigreturn trampoline
arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instruction
...
- Add the initrdmem= boot option to specify an initrd embedded in RAM (flash most likely)
- Sanitize the CS value earlier during boot, which also fixes SEV-ES.
- Various fixes and smaller cleanups.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=U/uh
-----END PGP SIGNATURE-----
Merge tag 'x86-boot-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
"Misc updates:
- Add the initrdmem= boot option to specify an initrd embedded in RAM
(flash most likely)
- Sanitize the CS value earlier during boot, which also fixes SEV-ES
- Various fixes and smaller cleanups"
* tag 'x86-boot-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot: Correct relocation destination on old linkers
x86/boot/compressed/64: Switch to __KERNEL_CS after GDT is loaded
x86/boot: Fix -Wint-to-pointer-cast build warning
x86/boot: Add kstrtoul() from lib/
x86/tboot: Mark tboot static
x86/setup: Add an initrdmem= option to specify initrd physical address
- RCU-tasks update, including addition of RCU Tasks Trace for
BPF use and TASKS_RUDE_RCU
- kfree_rcu() updates.
- Remove scheduler locking restriction
- RCU CPU stall warning updates.
- Torture-test updates.
- Miscellaneous fixes and other updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=Yisx
-----END PGP SIGNATURE-----
Merge tag 'core-rcu-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
"The RCU updates for this cycle were:
- RCU-tasks update, including addition of RCU Tasks Trace for BPF use
and TASKS_RUDE_RCU
- kfree_rcu() updates.
- Remove scheduler locking restriction
- RCU CPU stall warning updates.
- Torture-test updates.
- Miscellaneous fixes and other updates"
* tag 'core-rcu-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits)
rcu: Allow for smp_call_function() running callbacks from idle
rcu: Provide rcu_irq_exit_check_preempt()
rcu: Abstract out rcu_irq_enter_check_tick() from rcu_nmi_enter()
rcu: Provide __rcu_is_watching()
rcu: Provide rcu_irq_exit_preempt()
rcu: Make RCU IRQ enter/exit functions rely on in_nmi()
rcu/tree: Mark the idle relevant functions noinstr
x86: Replace ist_enter() with nmi_enter()
x86/mce: Send #MC singal from task work
x86/entry: Get rid of ist_begin/end_non_atomic()
sched,rcu,tracing: Avoid tracing before in_nmi() is correct
sh/ftrace: Move arch_ftrace_nmi_{enter,exit} into nmi exception
lockdep: Always inline lockdep_{off,on}()
hardirq/nmi: Allow nested nmi_enter()
arm64: Prepare arch_nmi_enter() for recursion
printk: Disallow instrumenting print_nmi_enter()
printk: Prepare for nested printk_nmi_enter()
rcutorture: Convert ULONG_CMP_LT() to time_before()
torture: Add a --kasan argument
torture: Save a few lines by using config_override_param initially
...
Make it possible to have a general notification queue built on top of a
standard pipe. Notifications are 'spliced' into the pipe and then read
out. splice(), vmsplice() and sendfile() are forbidden on pipes used for
notifications as post_one_notification() cannot take pipe->mutex. This
means that notifications could be posted in between individual pipe
buffers, making iov_iter_revert() difficult to effect.
The way the notification queue is used is:
(1) An application opens a pipe with a special flag and indicates the
number of messages it wishes to be able to queue at once (this can
only be set once):
pipe2(fds, O_NOTIFICATION_PIPE);
ioctl(fds[0], IOC_WATCH_QUEUE_SET_SIZE, queue_depth);
(2) The application then uses poll() and read() as normal to extract data
from the pipe. read() will return multiple notifications if the
buffer is big enough, but it will not split a notification across
buffers - rather it will return a short read or EMSGSIZE.
Notification messages include a length in the header so that the
caller can split them up.
Each message has a header that describes it:
struct watch_notification {
__u32 type:24;
__u32 subtype:8;
__u32 info;
};
The type indicates the source (eg. mount tree changes, superblock events,
keyring changes, block layer events) and the subtype indicates the event
type (eg. mount, unmount; EIO, EDQUOT; link, unlink). The info field
indicates a number of things, including the entry length, an ID assigned to
a watchpoint contributing to this buffer and type-specific flags.
Supplementary data, such as the key ID that generated an event, can be
attached in additional slots. The maximum message size is 127 bytes.
Messages may not be padded or aligned, so there is no guarantee, for
example, that the notification type will be on a 4-byte bounary.
Signed-off-by: David Howells <dhowells@redhat.com>
stack protector enabled.
-----BEGIN PGP SIGNATURE-----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=5Xi5
-----END PGP SIGNATURE-----
Merge tag 'x86_urgent_for_v5.7-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fix from Borislav Petkov:
"A single fix for early boot crashes of kernels built with gcc10 and
stack protector enabled"
* tag 'x86_urgent_for_v5.7-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Fix early boot crash on gcc-10, third try
On Fedora, linking static glibc requires the glibc-static RPM package,
which is not part of the glibc-devel package.
CONFIG_CC_CAN_LINK does not check the capability of static linking,
so you can enable CONFIG_BPFILTER_UMH, then fail to build:
HOSTLD net/bpfilter/bpfilter_umh
/usr/bin/ld: cannot find -lc
collect2: error: ld returned 1 exit status
Add CONFIG_CC_CAN_LINK_STATIC, and make CONFIG_BPFILTER_UMH depend
on it.
Reported-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
bpfilter_umh is built for the default machine bit of the compiler,
which may not match to the bit size of the kernel.
This happens in the scenario below:
You can use biarch GCC that defaults to 64-bit for building the 32-bit
kernel. In this case, Kbuild passes -m32 to teach the compiler to
produce 32-bit kernel space objects. However, it is missing when
building bpfilter_umh. It is built as a 64-bit ELF, and then embedded
into the 32-bit kernel.
The 32-bit kernel and 64-bit umh is a bad combination.
In theory, we can have 32-bit umh running on 64-bit kernel, but we do
not have a good reason to support such a usecase.
The best is to match the bit size between them.
Pass -m32 or -m64 to the umh build command if it is found in
$(KBUILD_CFLAGS). Evaluate CC_CAN_LINK against the kernel bit-size.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull networking fixes from David Miller:
1) Fix sk_psock reference count leak on receive, from Xiyu Yang.
2) CONFIG_HNS should be invisible, from Geert Uytterhoeven.
3) Don't allow locking route MTUs in ipv6, RFCs actually forbid this,
from Maciej Żenczykowski.
4) ipv4 route redirect backoff wasn't actually enforced, from Paolo
Abeni.
5) Fix netprio cgroup v2 leak, from Zefan Li.
6) Fix infinite loop on rmmod in conntrack, from Florian Westphal.
7) Fix tcp SO_RCVLOWAT hangs, from Eric Dumazet.
8) Various bpf probe handling fixes, from Daniel Borkmann.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (68 commits)
selftests: mptcp: pm: rm the right tmp file
dpaa2-eth: properly handle buffer size restrictions
bpf: Restrict bpf_trace_printk()'s %s usage and add %pks, %pus specifier
bpf: Add bpf_probe_read_{user, kernel}_str() to do_refine_retval_range
bpf: Restrict bpf_probe_read{, str}() only to archs where they work
MAINTAINERS: Mark networking drivers as Maintained.
ipmr: Add lockdep expression to ipmr_for_each_table macro
ipmr: Fix RCU list debugging warning
drivers: net: hamradio: Fix suspicious RCU usage warning in bpqether.c
net: phy: broadcom: fix BCM54XX_SHD_SCR3_TRDDAPD value for BCM54810
tcp: fix error recovery in tcp_zerocopy_receive()
MAINTAINERS: Add Jakub to networking drivers.
MAINTAINERS: another add of Karsten Graul for S390 networking
drivers: ipa: fix typos for ipa_smp2p structure doc
pppoe: only process PADT targeted at local interfaces
selftests/bpf: Enforce returning 0 for fentry/fexit programs
bpf: Enforce returning 0 for fentry/fexit progs
net: stmmac: fix num_por initialization
security: Fix the default value of secid_to_secctx hook
libbpf: Fix register naming in PT_REGS s390 macros
...
This change adds generic support for Clang's Shadow Call Stack,
which uses a shadow stack to protect return addresses from being
overwritten by an attacker. Details are available here:
https://clang.llvm.org/docs/ShadowCallStack.html
Note that security guarantees in the kernel differ from the ones
documented for user space. The kernel must store addresses of
shadow stacks in memory, which means an attacker capable reading
and writing arbitrary memory may be able to locate them and hijack
control flow by modifying the stacks.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
[will: Numerous cosmetic changes]
Signed-off-by: Will Deacon <will@kernel.org>
Given the legacy bpf_probe_read{,str}() BPF helpers are broken on archs
with overlapping address ranges, we should really take the next step to
disable them from BPF use there.
To generally fix the situation, we've recently added new helper variants
bpf_probe_read_{user,kernel}() and bpf_probe_read_{user,kernel}_str().
For details on them, see 6ae08ae3de ("bpf: Add probe_read_{user, kernel}
and probe_read_{user,kernel}_str helpers").
Given bpf_probe_read{,str}() have been around for ~5 years by now, there
are plenty of users at least on x86 still relying on them today, so we
cannot remove them entirely w/o breaking the BPF tracing ecosystem.
However, their use should be restricted to archs with non-overlapping
address ranges where they are working in their current form. Therefore,
move this behind a CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE and
have x86, arm64, arm select it (other archs supporting it can follow-up
on it as well).
For the remaining archs, they can workaround easily by relying on the
feature probe from bpftool which spills out defines that can be used out
of BPF C code to implement the drop-in replacement for old/new kernels
via: bpftool feature probe macro
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/bpf/20200515101118.6508-2-daniel@iogearbox.net
... or the odyssey of trying to disable the stack protector for the
function which generates the stack canary value.
The whole story started with Sergei reporting a boot crash with a kernel
built with gcc-10:
Kernel panic — not syncing: stack-protector: Kernel stack is corrupted in: start_secondary
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc5—00235—gfffb08b37df9 #139
Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M—D3H, BIOS F12 11/14/2013
Call Trace:
dump_stack
panic
? start_secondary
__stack_chk_fail
start_secondary
secondary_startup_64
-—-[ end Kernel panic — not syncing: stack—protector: Kernel stack is corrupted in: start_secondary
This happens because gcc-10 tail-call optimizes the last function call
in start_secondary() - cpu_startup_entry() - and thus emits a stack
canary check which fails because the canary value changes after the
boot_init_stack_canary() call.
To fix that, the initial attempt was to mark the one function which
generates the stack canary with:
__attribute__((optimize("-fno-stack-protector"))) ... start_secondary(void *unused)
however, using the optimize attribute doesn't work cumulatively
as the attribute does not add to but rather replaces previously
supplied optimization options - roughly all -fxxx options.
The key one among them being -fno-omit-frame-pointer and thus leading to
not present frame pointer - frame pointer which the kernel needs.
The next attempt to prevent compilers from tail-call optimizing
the last function call cpu_startup_entry(), shy of carving out
start_secondary() into a separate compilation unit and building it with
-fno-stack-protector, was to add an empty asm("").
This current solution was short and sweet, and reportedly, is supported
by both compilers but we didn't get very far this time: future (LTO?)
optimization passes could potentially eliminate this, which leads us
to the third attempt: having an actual memory barrier there which the
compiler cannot ignore or move around etc.
That should hold for a long time, but hey we said that about the other
two solutions too so...
Reported-by: Sergei Trofimovich <slyfox@gentoo.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Kalle Valo <kvalo@codeaurora.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200314164451.346497-1-slyfox@gentoo.org
Unfortunately, the last set of fixes introduced some minor bugs:
- The bootconfig apply_xbc() leak fix caused the application to return
a positive number on success, when it should have returned zero.
- The preempt_irq_delay_thread fix to make the creation code
wait for the kthread to finish to prevent it from executing after
module unload, can now cause the kthread to exit before it even
executes (preventing it to run its tests).
- The fix to the bootconfig that fixed the initrd to remove the
bootconfig from causing the kernel to panic, now prints a warning
that the bootconfig is not found, even when bootconfig is not
on the command line.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXrq2ehQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qrdjAQDGNaJa7Ft13KTDTNTioKmOorOi38vF
ava4E3uBHl3StQD/anJmVq7Kk4WJFKGYemV6usbjDqy510PCFu/VQ1AbGQc=
=hJvk
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Fixes to previous fixes.
Unfortunately, the last set of fixes introduced some minor bugs:
- The bootconfig apply_xbc() leak fix caused the application to
return a positive number on success, when it should have returned
zero.
- The preempt_irq_delay_thread fix to make the creation code wait for
the kthread to finish to prevent it from executing after module
unload, can now cause the kthread to exit before it even executes
(preventing it to run its tests).
- The fix to the bootconfig that fixed the initrd to remove the
bootconfig from causing the kernel to panic, now prints a warning
that the bootconfig is not found, even when bootconfig is not on
the command line"
* tag 'trace-v5.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
bootconfig: Fix to prevent warning message if no bootconfig option
tracing: Wait for preempt irq delay thread to execute
tools/bootconfig: Fix apply_xbc() to return zero on success
Commit de462e5f10 ("bootconfig: Fix to remove bootconfig
data from initrd while boot") causes a cosmetic regression
on dmesg, which warns "no bootconfig data" message without
bootconfig cmdline option.
Fix setup_boot_config() by moving no bootconfig check after
commandline option check.
Link: http://lkml.kernel.org/r/9b1ba335-071d-c983-89a4-2677b522dcc8@molgen.mpg.de
Link: http://lkml.kernel.org/r/158916116468.21787.14558782332170588206.stgit@devnote2
Fixes: de462e5f10 ("bootconfig: Fix to remove bootconfig data from initrd while boot")
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Similarly to the CC_IS_CLANG config, add LD_IS_LLD to avoid GNU ld
specific logic such as ld-version or ld-ifversion and gain the
ability to select potential features that depend on the linker at
configuration time such as LTO.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Masahiro Yamada <masahiroy@kernel.org>
[nc: Reword commit message]
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
scripts/mkcompile_h runs $(CC) just for getting the version string.
Reuse CONFIG_CC_VERSION_TEXT for optimization.
For GCC, this slightly changes the version string. I do not think it
is a big deal as we do not have the defined format for LINUX_COMPILER.
In fact, the recent commit 4dcc9a8844 ("kbuild: mkcompile_h:
Include $LD version in /proc/version") added the linker version.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Commit 21c54b7747 ("kconfig: show compiler version text in the top
comment") added the environment variable, CC_VERSION_TEXT in the comment
of the top Kconfig file. It can detect the compiler update, and invoke
the syncconfig because all environment variables referenced in Kconfig
files are recorded in include/config/auto.conf.cmd
This commit makes it a CONFIG option in order to ensure the full rebuild
when the compiler is updated.
This works like follows:
include/config/kconfig.h contains "CONFIG_CC_VERSION_TEXT" in the comment
block.
The top Makefile specifies "-include $(srctree)/include/linux/kconfig.h"
to guarantee it is included from all kernel source files.
fixdep parses every source file and all headers included from it,
searching for words prefixed with "CONFIG_". Then, fixdep finds
CONFIG_CC_VERSION_TEXT in include/config/kconfig.h and adds
include/config/cc/version/text.h into every .*.cmd file.
When the compiler is updated, syncconfig is invoked because init/Kconfig
contains the reference to the environment variable CC_VERTION_TEXT.
CONFIG_CC_VERSION_TEXT is updated to the new version string, and
include/config/cc/version/text.h is touched.
In the next rebuild, Make will rebuild every files since the timestamp
of include/config/cc/version/text.h is newer than that of target.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The result of '$(CC) --version | head -n 1' has already been computed
by the top Makefile, and stored in the environment variable,
CC_VERSION_TEXT.
'echo' is cheaper than the two commands $(CC) and 'head' although this
optimization is not noticeable level.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
It seems that for whatever reason, gcc-10 ends up not inlining a couple
of functions that used to be inlined before. Even if they only have one
single callsite - it looks like gcc may have decided that the code was
unlikely, and not worth inlining.
The code generation difference is harmless, but caused a few new section
mismatch errors, since the (now no longer inlined) function wasn't in
the __init section, but called other init functions:
Section mismatch in reference from the function kexec_free_initrd() to the function .init.text:free_initrd_mem()
Section mismatch in reference from the function tpm2_calc_event_log_size() to the function .init.text:early_memremap()
Section mismatch in reference from the function tpm2_calc_event_log_size() to the function .init.text:early_memunmap()
So add the appropriate __init annotation to make modpost not complain.
In both cases there were trivially just a single callsite from another
__init function.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We have some rather random rules about when we accept the
"maybe-initialized" warnings, and when we don't.
For example, we consider it unreliable for gcc versions < 4.9, but also
if -O3 is enabled, or if optimizing for size. And then various kernel
config options disabled it, because they know that they trigger that
warning by confusing gcc sufficiently (ie PROFILE_ALL_BRANCHES).
And now gcc-10 seems to be introducing a lot of those warnings too, so
it falls under the same heading as 4.9 did.
At the same time, we have a very straightforward way to _enable_ that
warning when wanted: use "W=2" to enable more warnings.
So stop playing these ad-hoc games, and just disable that warning by
default, with the known and straight-forward "if you want to work on the
extra compiler warnings, use W=123".
Would it be great to have code that is always so obvious that it never
confuses the compiler whether a variable is used initialized or not?
Yes, it would. In a perfect world, the compilers would be smarter, and
our source code would be simpler.
That's currently not the world we live in, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If there is a bootconfig data in the tail of initrd/initramfs,
initrd image sanity check caused an error while decompression
stage as follows.
[ 0.883882] Unpacking initramfs...
[ 2.696429] Initramfs unpacking failed: invalid magic at start of compressed archive
This error will be ignored if CONFIG_BLK_DEV_RAM=n,
but CONFIG_BLK_DEV_RAM=y the kernel failed to mount rootfs
and causes a panic.
To fix this issue, shrink down the initrd_end for removing
tailing bootconfig data while boot the kernel.
Link: http://lkml.kernel.org/r/158788401014.24243.17424755854115077915.stgit@devnote2
Cc: Borislav Petkov <bp@alien8.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Fixes: 7684b8582c ("bootconfig: Load boot config from the tail of initrd")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit splits ->trc_reader_need_end by using the rcu_special union.
This change permits readers to check to see if a memory barrier is
required without any added overhead in the common case where no such
barrier is required. This commit also adds the read-side checking.
Later commits will add the machinery to properly set the new
->trc_reader_special.b.need_mb field.
This commit also makes rcu_read_unlock_trace_special() tolerate nested
read-side critical sections within interrupt and NMI handlers.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Because RCU does not watch exception early-entry/late-exit, idle-loop,
or CPU-hotplug execution, protection of tracing and BPF operations is
needlessly complicated. This commit therefore adds a variant of
Tasks RCU that:
o Has explicit read-side markers to allow finite grace periods in
the face of in-kernel loops for PREEMPT=n builds. These markers
are rcu_read_lock_trace() and rcu_read_unlock_trace().
o Protects code in the idle loop, exception entry/exit, and
CPU-hotplug code paths. In this respect, RCU-tasks trace is
similar to SRCU, but with lighter-weight readers.
o Avoids expensive read-side instruction, having overhead similar
to that of Preemptible RCU.
There are of course downsides:
o The grace-period code can send IPIs to CPUs, even when those
CPUs are in the idle loop or in nohz_full userspace. This is
mitigated by later commits.
o It is necessary to scan the full tasklist, much as for Tasks RCU.
o There is a single callback queue guarded by a single lock,
again, much as for Tasks RCU. However, those early use cases
that request multiple grace periods in quick succession are
expected to do so from a single task, which makes the single
lock almost irrelevant. If needed, multiple callback queues
can be provided using any number of schemes.
Perhaps most important, this variant of RCU does not affect the vanilla
flavors, rcu_preempt and rcu_sched. The fact that RCU Tasks Trace
readers can operate from idle, offline, and exception entry/exit in no
way enables rcu_preempt and rcu_sched readers to do so.
The memory ordering was outlined here:
https://lore.kernel.org/lkml/20200319034030.GX3199@paulmck-ThinkPad-P72/
This effort benefited greatly from off-list discussions of BPF
requirements with Alexei Starovoitov and Andrii Nakryiko. At least
some of the on-list discussions are captured in the Link: tags below.
In addition, KCSAN was quite helpful in finding some early bugs.
Link: https://lore.kernel.org/lkml/20200219150744.428764577@infradead.org/
Link: https://lore.kernel.org/lkml/87mu8p797b.fsf@nanos.tec.linutronix.de/
Link: https://lore.kernel.org/lkml/20200225221305.605144982@linutronix.de/
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Andrii Nakryiko <andriin@fb.com>
[ paulmck: Apply feedback from Steve Rostedt and Joel Fernandes. ]
[ paulmck: Decrement trc_n_readers_need_end upon IPI failure. ]
[ paulmck: Fix locking issue reported by rcutorture. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Add the initrdmem option:
initrdmem=ss[KMG],nn[KMG]
which is used to specify the physical address of the initrd, almost
always an address in FLASH. Also add code for x86 to use the existing
phys_init_start and phys_init_size variables in the kernel.
This is useful in cases where a kernel and an initrd is placed in FLASH,
but there is no firmware file system structure in the FLASH.
One such situation occurs when unused FLASH space on UEFI systems has
been reclaimed by, e.g., taking it from the Management Engine. For
example, on many systems, the ME is given half the FLASH part; not only
is 2.75M of an 8M part unused; but 10.75M of a 16M part is unused. This
space can be used to contain an initrd, but need to tell Linux where it
is.
This space is "raw": due to, e.g., UEFI limitations: it can not be added
to UEFI firmware volumes without rebuilding UEFI from source or writing
a UEFI device driver. It can be referenced only as a physical address
and size.
At the same time, if a kernel can be "netbooted" or loaded from GRUB or
syslinux, the option of not using the physical address specification
should be available.
Then, it is easy to boot the kernel and provide an initrd; or boot the
the kernel and let it use the initrd in FLASH. In practice, this has
proven to be very helpful when integrating Linux into FLASH on x86.
Hence, the most flexible and convenient path is to enable the initrdmem
command line option in a way that it is the last choice tried.
For example, on the DigitalLoggers Atomic Pi, an image into FLASH can be
burnt in with a built-in command line which includes:
initrdmem=0xff968000,0x200000
which specifies a location and size.
[ bp: Massage commit message, make it passive. ]
[akpm@linux-foundation.org: coding style fixes]
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Link: http://lkml.kernel.org/r/CAP6exYLK11rhreX=6QPyDQmW7wPHsKNEFtXE47pjx41xS6O7-A@mail.gmail.com
Link: https://lkml.kernel.org/r/20200426011021.1cskg0AGd%akpm@linux-foundation.org
It is very rare to see versions of GCC prior to 4.8 being used to build
the mainline kernel. These old compilers are also know to have codegen
issues which can lead to silent miscompilation:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145
Raise the minimum GCC version for kernel build to 4.8 and remove some
tautological Kconfig dependencies as a consequence.
Cc: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
This adds support for scoped accesses, where the memory range is checked
for the duration of the scope. The feature is implemented by inserting
the relevant access information into a list of scoped accesses for
the current execution context, which are then checked (until removed)
on every call (through instrumentation) into the KCSAN runtime.
An alternative, more complex, implementation could set up a watchpoint for
the scoped access, and keep the watchpoint set up. This, however, would
require first exposing a handle to the watchpoint, as well as dealing
with cases such as accesses by the same thread while the watchpoint is
still set up (and several more cases). It is also doubtful if this would
provide any benefit, since the majority of delay where the watchpoint
is set up is likely due to the injected delays by KCSAN. Therefore,
the implementation in this patch is simpler and avoids hurting KCSAN's
main use-case (normal data race detection); it also implicitly increases
scoped-access race-detection-ability due to increased probability of
setting up watchpoints by repeatedly calling __kcsan_check_access()
throughout the scope of the access.
The implementation required adding an additional conditional branch to
the fast-path. However, the microbenchmark showed a *speedup* of ~5%
on the fast-path. This appears to be due to subtly improved codegen by
GCC from moving get_ctx() and associated load of preempt_count earlier.
Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
-----BEGIN PGP SIGNATURE-----
iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl6TbaUeHHRvcnZhbGRz
QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGhgkH/iWpiKvosA20HJjC
rBqYeJPxQsgZTuBieWJ+MeVxbpcF7RlM4c+glyvg3QJhHwIEG58dl6LBrQbAyBAR
aFHNojr1iAYOruVCGnU3pA008YZiwUIDv/ZQ4DF8fmIU2vI2mJ6qHBv3XDl4G2uR
Nwz8Eu9AgIwZM5coomVOSmoWyFy7Vxmb7W+3t5VmKsvOWx4ib9kyQtOIkvQDEl7j
XCbWfI0xDQr6LFOm4jnCi5R/LhJ2LIqqIvHHrunbpszM8IwK797jCXz4im+dmd5Y
+km46N7a8pDqri36xXz1gdBAU3eG7Pt1NyvfjwRVTdX4GquQ2MT0GoojxbLxUP3y
3pEsQuE=
=whbL
-----END PGP SIGNATURE-----
Merge tag 'v5.7-rc1' into locking/kcsan, to resolve conflicts and refresh
Resolve these conflicts:
arch/x86/Kconfig
arch/x86/kernel/Makefile
Do a minor "evil merge" to move the KCSAN entry up a bit by a few lines
in the Kconfig to reduce the probability of future conflicts.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- raise minimum supported binutils version to 2.23
- remove old CONFIG_AS_* macros that we know binutils >= 2.23 supports
- move remaining CONFIG_AS_* tests to Kconfig from Makefile
- enable -Wtautological-compare warnings to catch more issues
- do not support GCC plugins for GCC <= 4.7
- fix various breakages of 'make xconfig'
- include the linker version used for linking the kernel into
LINUX_COMPILER, which is used for the banner, and also exposed to
/proc/version
- link lib-y objects to vmlinux forcibly when CONFIG_MODULES=y,
which allows us to remove the lib-ksyms.o workaround, and to
solve the last known issue of the LLVM linker
- add dummy tools in scripts/dummy-tools/ to enable all compiler
tests in Kconfig, which will be useful for distro maintainers
- support the single switch, LLVM=1 to use Clang and all LLVM utilities
instead of GCC and Binutils.
- support LLVM_IAS=1 to enable the integrated assembler, which is still
experimental
-----BEGIN PGP SIGNATURE-----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=jpyF
-----END PGP SIGNATURE-----
Merge tag 'kbuild-v5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull more Kbuild updates from Masahiro Yamada:
- raise minimum supported binutils version to 2.23
- remove old CONFIG_AS_* macros that we know binutils >= 2.23 supports
- move remaining CONFIG_AS_* tests to Kconfig from Makefile
- enable -Wtautological-compare warnings to catch more issues
- do not support GCC plugins for GCC <= 4.7
- fix various breakages of 'make xconfig'
- include the linker version used for linking the kernel into
LINUX_COMPILER, which is used for the banner, and also exposed to
/proc/version
- link lib-y objects to vmlinux forcibly when CONFIG_MODULES=y, which
allows us to remove the lib-ksyms.o workaround, and to solve the last
known issue of the LLVM linker
- add dummy tools in scripts/dummy-tools/ to enable all compiler tests
in Kconfig, which will be useful for distro maintainers
- support the single switch, LLVM=1 to use Clang and all LLVM utilities
instead of GCC and Binutils.
- support LLVM_IAS=1 to enable the integrated assembler, which is still
experimental
* tag 'kbuild-v5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (36 commits)
kbuild: fix comment about missing include guard detection
kbuild: support LLVM=1 to switch the default tools to Clang/LLVM
kbuild: replace AS=clang with LLVM_IAS=1
kbuild: add dummy toolchains to enable all cc-option etc. in Kconfig
kbuild: link lib-y objects to vmlinux forcibly when CONFIG_MODULES=y
MIPS: fw: arc: add __weak to prom_meminit and prom_free_prom_memory
kbuild: remove -I$(srctree)/tools/include from scripts/Makefile
kbuild: do not pass $(KBUILD_CFLAGS) to scripts/mkcompile_h
Documentation/llvm: fix the name of llvm-size
kbuild: mkcompile_h: Include $LD version in /proc/version
kconfig: qconf: Fix a few alignment issues
kconfig: qconf: remove some old bogus TODOs
kconfig: qconf: fix support for the split view mode
kconfig: qconf: fix the content of the main widget
kconfig: qconf: Change title for the item window
kconfig: qconf: clean deprecated warnings
gcc-plugins: drop support for GCC <= 4.7
kbuild: Enable -Wtautological-compare
x86: update AS_* macros to binutils >=2.23, supporting ADX and AVX2
crypto: x86 - clean up poly1305-x86_64-cryptogams.S by 'make clean'
...
printk_deferred(), similarly to printk_safe/printk_nmi, does not
immediately attempt to print a new message on the consoles, avoiding
calls into non-reentrant kernel paths, e.g. scheduler or timekeeping,
which potentially can deadlock the system.
Those printk() flavors, instead, rely on per-CPU flush irq_work to print
messages from safer contexts. For same reasons (recursive scheduler or
timekeeping calls) printk() uses per-CPU irq_work in order to wake up
user space syslog/kmsg readers.
However, only printk_safe/printk_nmi do make sure that per-CPU areas
have been initialised and that it's safe to modify per-CPU irq_work.
This means that, for instance, should printk_deferred() be invoked "too
early", that is before per-CPU areas are initialised, printk_deferred()
will perform illegal per-CPU access.
Lech Perczak [0] reports that after commit 1b710b1b10 ("char/random:
silence a lockdep splat with printk()") user-space syslog/kmsg readers
are not able to read new kernel messages.
The reason is printk_deferred() being called too early (as was pointed
out by Petr and John).
Fix printk_deferred() and do not queue per-CPU irq_work before per-CPU
areas are initialized.
Link: https://lore.kernel.org/lkml/aa0732c6-5c4e-8a8b-a1c1-75ebe3dca05b@camlintechnologies.com/
Reported-by: Lech Perczak <l.perczak@camlintechnologies.com>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Tested-by: Jann Horn <jannh@google.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Ensure that the compiler and linker versions are aligned so that ld
doesn't complain about not understanding a .note.gnu.property section
(emitted when pointer authentication is enabled).
- Force -mbranch-protection=none when the feature is not enabled, in
case a compiler may choose a different default value.
- Remove CONFIG_DEBUG_ALIGN_RODATA. It was never in defconfig and rarely
enabled.
- Fix checking 16-bit Thumb-2 instructions checking mask in the
emulation of the SETEND instruction (it could match the bottom half of
a 32-bit Thumb-2 instruction).
-----BEGIN PGP SIGNATURE-----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=pHRG
-----END PGP SIGNATURE-----
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Catalin Marinas:
- Ensure that the compiler and linker versions are aligned so that ld
doesn't complain about not understanding a .note.gnu.property section
(emitted when pointer authentication is enabled).
- Force -mbranch-protection=none when the feature is not enabled, in
case a compiler may choose a different default value.
- Remove CONFIG_DEBUG_ALIGN_RODATA. It was never in defconfig and
rarely enabled.
- Fix checking 16-bit Thumb-2 instructions checking mask in the
emulation of the SETEND instruction (it could match the bottom half
of a 32-bit Thumb-2 instruction).
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: armv8_deprecated: Fix undef_hook mask for thumb setend
arm64: remove CONFIG_DEBUG_ALIGN_RODATA feature
arm64: Always force a branch protection mode when the compiler has one
arm64: Kconfig: ptrauth: Add binutils version check to fix mismatch
init/kconfig: Add LD_VERSION Kconfig
scripts/mkcompile_h uses $(CC) only for getting the version string.
I suspected there was a specific reason why the additional flags were
needed, and dug the commit history. This code dates back to at least
2002 [1], but I could not get any more clue.
Just get rid of it.
[1]: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=29f3df7eba8ddf91a55183f9967f76fbcc3ab742
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
When doing Clang builds of the kernel, it is possible to link with
either ld.bfd (binutils) or ld.lld (LLVM), but it is not possible to
discover this from a running kernel. Add the "$LD -v" output to
/proc/version.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Fangrui Song <maskray@google.com>
Reviewed-by: Sedat Dilek <sedat.dilek@gmail.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Accurate userfaultfd WP tracking is possible by tracking exactly which
virtual memory ranges were writeprotected by userland. We can't relay
only on the RW bit of the mapped pagetable because that information is
destroyed by fork() or KSM or swap. If we were to relay on that, we'd
need to stay on the safe side and generate false positive wp faults for
every swapped out page.
[peterx@redhat.com: append _PAGE_UFD_WP to _PAGE_CHG_MASK]
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Shaohua Li <shli@fb.com>
Link: http://lkml.kernel.org/r/20200220163112.11409-4-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
core:
- Support for cgroup tracking in samples to allow cgroup based
analysis
tools:
- Support for cgroup analysis
- Commandline option and hotkey for perf top to change the sort order
- A set of fixes all over the place
- Various build system related improvements
- Updates of the X86 pmu event JSON data
- Documentation updates
-----BEGIN PGP SIGNATURE-----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=2UUD
-----END PGP SIGNATURE-----
Merge tag 'perf-urgent-2020-04-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull more perf updates from Thomas Gleixner:
"Perf updates all over the place:
core:
- Support for cgroup tracking in samples to allow cgroup based
analysis
tools:
- Support for cgroup analysis
- Commandline option and hotkey for perf top to change the sort order
- A set of fixes all over the place
- Various build system related improvements
- Updates of the X86 pmu event JSON data
- Documentation updates"
* tag 'perf-urgent-2020-04-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (55 commits)
perf python: Fix clang detection to strip out options passed in $CC
perf tools: Support Python 3.8+ in Makefile
perf script: Fix invalid read of directory entry after closedir()
perf script report: Fix SEGFAULT when using DWARF mode
perf script: add -S/--symbols documentation
perf pmu-events x86: Use CPU_CLK_UNHALTED.THREAD in Kernel_Utilization metric
perf events parser: Add missing Intel CPU events to parser
perf script: Allow --symbol to accept hexadecimal addresses
perf report/top TUI: Fix title line formatting
perf top: Support hotkey to change sort order
perf top: Support --group-sort-idx to change the sort order
perf symbols: Fix arm64 gap between kernel start and module end
perf build-test: Honour JOBS to override detection of number of cores
perf script: Add --show-cgroup-events option
perf top: Add --all-cgroups option
perf record: Add --all-cgroups option
perf record: Support synthesizing cgroup events
perf report: Add 'cgroup' sort key
perf cgroup: Maintain cgroup hierarchy
perf tools: Basic support for CGROUP event
...
- The ring buffer is no longer disabled when reading the trace file.
The trace_pipe file was made to be used for live tracing and reading
as it acted like the normal producer/consumer. As the trace file
would not consume the data, the easy way of handling it was to just
disable writes to the ring buffer. This came to a surprise to the
BPF folks who complained about lost events due to reading.
This is no longer an issue. If someone wants to keep the old disabling
there's a new option "pause-on-trace" that can be set.
- New set_ftrace_notrace_pid file. PIDs in this file will not be traced
by the function tracer. Similar to set_ftrace_pid, which makes the
function tracer only trace those tasks with PIDs in the file, the
set_ftrace_notrace_pid does the reverse.
- New set_event_notrace_pid file. PIDs in this file will cause events
not to be traced if triggered by a task with a matching PID.
Similar to the set_event_pid file but will not be traced.
Note, sched_waking and sched_switch events may still be trace if
one of the tasks referenced by those events contains a PID that
is allowed to be traced.
Tracing related features:
- New bootconfig option, that is attached to the initrd file.
If bootconfig is on the command line, then the initrd file
is searched looking for a bootconfig appended at the end.
- New GPU tracepoint infrastructure to help the gfx drivers to get
off debugfs (acked by Greg Kroah-Hartman)
Other minor updates and fixes.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXokgWRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qgrHAP0UkKs/52JY4oWa3OIh/OqK+vnCrIwz
zGvDFOYM0fKbwgD9FZWgzlcaYK5m2Cxlhp4VoraZveHMLJUhnEHtdX6X0wk=
=Rebj
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"New tracing features:
- The ring buffer is no longer disabled when reading the trace file.
The trace_pipe file was made to be used for live tracing and
reading as it acted like the normal producer/consumer. As the trace
file would not consume the data, the easy way of handling it was to
just disable writes to the ring buffer.
This came to a surprise to the BPF folks who complained about lost
events due to reading. This is no longer an issue. If someone wants
to keep the old disabling there's a new option "pause-on-trace"
that can be set.
- New set_ftrace_notrace_pid file. PIDs in this file will not be
traced by the function tracer.
Similar to set_ftrace_pid, which makes the function tracer only
trace those tasks with PIDs in the file, the set_ftrace_notrace_pid
does the reverse.
- New set_event_notrace_pid file. PIDs in this file will cause events
not to be traced if triggered by a task with a matching PID.
Similar to the set_event_pid file but will not be traced. Note,
sched_waking and sched_switch events may still be traced if one of
the tasks referenced by those events contains a PID that is allowed
to be traced.
Tracing related features:
- New bootconfig option, that is attached to the initrd file.
If bootconfig is on the command line, then the initrd file is
searched looking for a bootconfig appended at the end.
- New GPU tracepoint infrastructure to help the gfx drivers to get
off debugfs (acked by Greg Kroah-Hartman)
And other minor updates and fixes"
* tag 'trace-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (27 commits)
tracing: Do not allocate buffer in trace_find_next_entry() in atomic
tracing: Add documentation on set_ftrace_notrace_pid and set_event_notrace_pid
selftests/ftrace: Add test to test new set_event_notrace_pid file
selftests/ftrace: Add test to test new set_ftrace_notrace_pid file
tracing: Create set_event_notrace_pid to not trace tasks
ftrace: Create set_ftrace_notrace_pid to not trace tasks
ftrace: Make function trace pid filtering a bit more exact
ftrace/kprobe: Show the maxactive number on kprobe_events
tracing: Have the document reflect that the trace file keeps tracing enabled
ring-buffer/tracing: Have iterator acknowledge dropped events
tracing: Do not disable tracing when reading the trace file
ring-buffer: Do not disable recording when there is an iterator
ring-buffer: Make resize disable per cpu buffer instead of total buffer
ring-buffer: Optimize rb_iter_head_event()
ring-buffer: Do not die if rb_iter_peek() fails more than thrice
ring-buffer: Have rb_iter_head_event() handle concurrent writer
ring-buffer: Add page_stamp to iterator for synchronization
ring-buffer: Rename ring_buffer_read() to read_buffer_iter_advance()
ring-buffer: Have ring_buffer_empty() not depend on tracing stopped
tracing: Save off entry when peeking at next entry
...
perf python:
Arnaldo Carvalho de Melo:
- Fix clang detection to strip out options passed in $CC.
build:
He Zhe:
- Normalize gcc parameter when generating arch errno table, fixing
the build by removing options from $(CC).
Sam Lunt:
- Support Python 3.8+ in Makefile.
perf report/top:
Arnaldo Carvalho de Melo:
- Fix title line formatting.
perf script:
Andreas Gerstmayr:
- Fix SEGFAULT when using DWARF mode.
- Fix invalid read of directory entry after closedir(), found with valgrind.
Hagen Paul Pfeifer:
- Introduce --deltatime option.
Stephane Eranian:
- Allow --symbol to accept hexadecimal addresses.
Ian Rogers:
- Add -S/--symbols documentation
Namhyung Kim:
- Add --show-cgroup-events option.
perf python:
Arnaldo Carvalho de Melo:
- Include rwsem.c in the python binding, needed by the cgroups improvements.
build-test:
Arnaldo Carvalho de Melo:
- Honour JOBS to override detection of number of cores
perf top:
Jin Yao:
- Support --group-sort-idx to change the sort order
- perf top: Support hotkey to change sort order
perf pmu-events x86:
Jin Yao:
- Use CPU_CLK_UNHALTED.THREAD in Kernel_Utilization metric
perf symbols arm64:
Kemeng Shi:
- Fix arm64 gap between kernel start and module end
kernel perf subsystem:
Namhyung Kim:
- Add PERF_RECORD_CGROUP event and Add PERF_SAMPLE_CGROUP feature,
to allow cgroup tracking, saving a link between cgroup path and
its id number.
perf cgroup:
Namhyung Kim:
- Maintain cgroup hierarchy.
perf report:
Namhyung Kim:
- Add 'cgroup' sort key.
perf record:
Namhyung Kim:
- Support synthesizing cgroup events for pre-existing cgroups.
- Add --all-cgroups option
Documentation:
Tony Jones:
- Update docs regarding kernel/user space unwinding.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQR2GiIUctdOfX2qHhGyPKLppCJ+JwUCXodMtwAKCRCyPKLppCJ+
J+leAP0Ws0dGzMSIwcMVc7zvK1IsYOTlZ8lYXJePxD+Po/YPdAEA6Squf4gwZ2wm
b9R7w50dlCkMJ9LaueCeZZjh/4asFwQ=
=auOb
-----END PGP SIGNATURE-----
Merge tag 'perf-urgent-for-mingo-5.7-20200403' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/urgent fixes and improvements from Arnaldo Carvalho de Melo:
perf python:
Arnaldo Carvalho de Melo:
- Fix clang detection to strip out options passed in $CC.
build:
He Zhe:
- Normalize gcc parameter when generating arch errno table, fixing
the build by removing options from $(CC).
Sam Lunt:
- Support Python 3.8+ in Makefile.
perf report/top:
Arnaldo Carvalho de Melo:
- Fix title line formatting.
perf script:
Andreas Gerstmayr:
- Fix SEGFAULT when using DWARF mode.
- Fix invalid read of directory entry after closedir(), found with valgrind.
Hagen Paul Pfeifer:
- Introduce --deltatime option.
Stephane Eranian:
- Allow --symbol to accept hexadecimal addresses.
Ian Rogers:
- Add -S/--symbols documentation
Namhyung Kim:
- Add --show-cgroup-events option.
perf python:
Arnaldo Carvalho de Melo:
- Include rwsem.c in the python binding, needed by the cgroups improvements.
build-test:
Arnaldo Carvalho de Melo:
- Honour JOBS to override detection of number of cores
perf top:
Jin Yao:
- Support --group-sort-idx to change the sort order
- perf top: Support hotkey to change sort order
perf pmu-events x86:
Jin Yao:
- Use CPU_CLK_UNHALTED.THREAD in Kernel_Utilization metric
perf symbols arm64:
Kemeng Shi:
- Fix arm64 gap between kernel start and module end
kernel perf subsystem:
Namhyung Kim:
- Add PERF_RECORD_CGROUP event and Add PERF_SAMPLE_CGROUP feature,
to allow cgroup tracking, saving a link between cgroup path and
its id number.
perf cgroup:
Namhyung Kim:
- Maintain cgroup hierarchy.
perf report:
Namhyung Kim:
- Add 'cgroup' sort key.
perf record:
Namhyung Kim:
- Support synthesizing cgroup events for pre-existing cgroups.
- Add --all-cgroups option
Documentation:
Tony Jones:
- Update docs regarding kernel/user space unwinding.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull exec/proc updates from Eric Biederman:
"This contains two significant pieces of work: the work to sort out
proc_flush_task, and the work to solve a deadlock between strace and
exec.
Fixing proc_flush_task so that it no longer requires a persistent
mount makes improvements to proc possible. The removal of the
persistent mount solves an old regression that that caused the hidepid
mount option to only work on remount not on mount. The regression was
found and reported by the Android folks. This further allows Alexey
Gladkov's work making proc mount options specific to an individual
mount of proc to move forward.
The work on exec starts solving a long standing issue with exec that
it takes mutexes of blocking userspace applications, which makes exec
extremely deadlock prone. For the moment this adds a second mutex with
a narrower scope that handles all of the easy cases. Which makes the
tricky cases easy to spot. With a little luck the code to solve those
deadlocks will be ready by next merge window"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (25 commits)
signal: Extend exec_id to 64bits
pidfd: Use new infrastructure to fix deadlocks in execve
perf: Use new infrastructure to fix deadlocks in execve
proc: io_accounting: Use new infrastructure to fix deadlocks in execve
proc: Use new infrastructure to fix deadlocks in execve
kernel/kcmp.c: Use new infrastructure to fix deadlocks in execve
kernel: doc: remove outdated comment cred.c
mm: docs: Fix a comment in process_vm_rw_core
selftests/ptrace: add test cases for dead-locks
exec: Fix a deadlock in strace
exec: Add exec_update_mutex to replace cred_guard_mutex
exec: Move exec_mmap right after de_thread in flush_old_exec
exec: Move cleanup of posix timers on exec out of de_thread
exec: Factor unshare_sighand out of de_thread and call it separately
exec: Only compute current once in flush_old_exec
pid: Improve the comment about waiting in zap_pid_ns_processes
proc: Remove the now unnecessary internal mount of proc
uml: Create a private mount of proc for mconsole
uml: Don't consult current to find the proc_mnt in mconsole_proc
proc: Use a list of inodes to flush from proc
...
This option can be used in Kconfig files to compare the ld version
and enable/disable incompatible config options if required.
This option is used in the subsequent patch along with GCC_VERSION to
filter out an incompatible feature.
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
