The UML port uses 4 and 5 level fixups to support higher level page
table directories in the generic VM code.
Implement primitives necessary for the 4th level folding, add walks of
p4d level where appropriate and drop usage of __ARCH_USE_5LEVEL_HACK.
Link: http://lkml.kernel.org/r/1572938135-31886-13-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
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: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The naming of pgtable_page_{ctor,dtor}() seems to have confused a few
people, and until recently arm64 used these erroneously/pointlessly for
other levels of page table.
To make it incredibly clear that these only apply to the PTE level, and to
align with the naming of pgtable_pmd_page_{ctor,dtor}(), let's rename them
to pgtable_pte_page_{ctor,dtor}().
These changes were generated with the following shell script:
----
git grep -lw 'pgtable_page_.tor' | while read FILE; do
sed -i '{s/pgtable_page_ctor/pgtable_pte_page_ctor/}' $FILE;
sed -i '{s/pgtable_page_dtor/pgtable_pte_page_dtor/}' $FILE;
done
----
... with the documentation re-flowed to remain under 80 columns, and
whitespace fixed up in macros to keep backslashes aligned.
There should be no functional change as a result of this patch.
Link: http://lkml.kernel.org/r/20190722141133.3116-1-mark.rutland@arm.com
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Both pgtable_cache_init() and pgd_cache_init() are used to initialize kmem
cache for page table allocations on several architectures that do not use
PAGE_SIZE tables for one or more levels of the page table hierarchy.
Most architectures do not implement these functions and use __weak default
NOP implementation of pgd_cache_init(). Since there is no such default
for pgtable_cache_init(), its empty stub is duplicated among most
architectures.
Rename the definitions of pgd_cache_init() to pgtable_cache_init() and
drop empty stubs of pgtable_cache_init().
Link: http://lkml.kernel.org/r/1566457046-22637-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Will Deacon <will@kernel.org> [arm64]
Acked-by: Thomas Gleixner <tglx@linutronix.de> [x86]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm: remove quicklist page table caches".
A while ago Nicholas proposed to remove quicklist page table caches [1].
I've rebased his patch on the curren upstream and switched ia64 and sh to
use generic versions of PTE allocation.
[1] https://lore.kernel.org/linux-mm/20190711030339.20892-1-npiggin@gmail.com
This patch (of 3):
Remove page table allocator "quicklists". These have been around for a
long time, but have not got much traction in the last decade and are only
used on ia64 and sh architectures.
The numbers in the initial commit look interesting but probably don't
apply anymore. If anybody wants to resurrect this it's in the git
history, but it's unhelpful to have this code and divergent allocator
behaviour for minor archs.
Also it might be better to instead make more general improvements to page
allocator if this is still so slow.
Link: http://lkml.kernel.org/r/1565250728-21721-2-git-send-email-rppt@linux.ibm.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert files to use SPDX header. All files are licensed under the GPLv2.
Signed-off-by: Alex Dewar <alex.dewar@gmx.co.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
This module allows virtio devices to be used over a vhost-user socket.
Signed-off-by: Erel Geron <erelx.geron@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
UML has its own platform-specific barrier.h under arch/x86/um/,
which should get used. Fix the build system to use it, and then
fix the barrier.h to actually compile.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Periodic timers are broken, because the also only fire once.
As it happens, Linux doesn't care because it only sets the
timer to periodic very briefly during boot, and then switches
it only between one-shot and off later.
Nevertheless, fix the logic (we shouldn't even be looking at
time_travel_timer_expiry unless the timer is enabled) and
change the code to fire the timer periodically in periodic
mode, in case it ever gets used in the future.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
We do need to call the constructors for *modules*, and
at least for KASAN in the future, we must call even the
kernel constructors only later when the kernel has been
initialized.
Instead of relying on libc to call them, emit an empty
section for libc and let the kernel's CONSTRUCTORS code
do the rest of the job.
Tested that it indeed doesn't work in modules, and does
work after the fixes in both, with a few functions with
__attribute__((constructor)) in both dynamic and static
builds.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
UML enables TRACE_IRQFLAGS_SUPPORT but doesn't actually implement
it. It seems to have been added for lockdep support, but that can't
actually really work well without IRQ flags tracing, as is also
very noisily reported when enabling CONFIG_DEBUG_LOCKDEP.
Implement it now.
Fixes: 711553efa5 ("[PATCH] uml: declare in Kconfig our partial LOCKDEP support")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Due to the typo in the name, this can never be used, but
it's also misleading because our value for enabled/disabled
is always just 0/1, not an actual signal mask.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Anton Ivanov <anton.ivanov@cambridgegreys.co.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
Fix an off-by-one in IRQ enumeration
Fixes: 49da7e64f3 ("High Performance UML Vector Network Driver")
Reported by: Dana Johnson <djohns042@gmail.com>
Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Unfortunately, my build fix for when time travel mode isn't
enabled broke time travel mode, because I forgot that we need
to use the timer time after the timer has been marked disabled,
and thus need to leave the time stored instead of zeroing it.
Fix that by splitting the inline into two, so we can call only
the _mode() one in the relevant code path.
Fixes: b482e48d29 ("um: fix build without CONFIG_UML_TIME_TRAVEL_SUPPORT")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
- A new timer mode, time travel, for testing with UML
- Many bugixes/improvements for the serial line driver
- Various bugfixes
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Merge tag 'for-linus-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger:
- A new timer mode, time travel, for testing with UML
- Many bugixes/improvements for the serial line driver
- Various bugfixes
* tag 'for-linus-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
um: fix build without CONFIG_UML_TIME_TRAVEL_SUPPORT
um: Fix kcov crash during startup
um: configs: Remove useless UEVENT_HELPER_PATH
um: Support time travel mode
um: Pass nsecs to os timer functions
um: Remove drivers/ssl.h
um: Don't garbage collect in deactivate_all_fds()
um: Silence lockdep complaint about mmap_sem
um: Remove locking in deactivate_all_fds()
um: Timer code cleanup
um: fix os_timer_one_shot()
um: Fix IRQ controller regression on console read
um allocates PTE pages with __get_free_page() and uses
GFP_KERNEL | __GFP_ZERO for the allocations.
Switch it to the generic version that does exactly the same thing for the
kernel page tables and adds __GFP_ACCOUNT for the user PTEs.
The pte_free() and pte_free_kernel() versions are identical to the generic
ones and can be simply dropped.
Link: http://lkml.kernel.org/r/1557296232-15361-14-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Acked-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Guo Ren <ren_guo@c-sky.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When CONFIG_UML_TIME_TRAVEL_SUPPORT isn't set, the build was broken.
Fix this.
Fixes: 065038706f ("um: Support time travel mode")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Sometimes it can be useful to run with "time travel" inside the
UML instance, for example for testing. For example, some tests
for the wireless subsystem and userspace are based on hwsim, a
virtual wireless adapter. Some tests can take a long time to
run because they e.g. wait for 120 seconds to elapse for some
regulatory checks. This obviously goes faster if it need not
actually wait that long, but time inside the test environment
just "bumps up" when there's nothing to do.
Add CONFIG_UML_TIME_TRAVEL_SUPPORT to enable code to support
such modes at runtime, selected on the command line:
* just "time-travel", in which time inside the UML instance
can move faster than real time, if there's nothing to do
* "time-travel=inf-cpu" in which time also moves slower and
any CPU processing takes no time at all, which allows to
implement consistent behaviour regardless of host CPU load
(or speed) or debug overhead.
An additional "time-travel-start=<seconds>" parameter is also
supported in this case to start the wall clock at this time
(in unix epoch).
With this enabled, the test mentioned above goes from a runtime
of about 140 seconds (with startup overhead and all) to being
CPU bound and finishing in 15 seconds (on my slow laptop).
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This makes the code clearer and lets the time travel patch have
the actual time used for these functions in just one place.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
When we get into activate_mm(), lockdep complains that we're doing
something strange:
WARNING: possible circular locking dependency detected
5.1.0-10252-gb00152307319-dirty #121 Not tainted
------------------------------------------------------
inside.sh/366 is trying to acquire lock:
(____ptrval____) (&(&p->alloc_lock)->rlock){+.+.}, at: flush_old_exec+0x703/0x8d7
but task is already holding lock:
(____ptrval____) (&mm->mmap_sem){++++}, at: flush_old_exec+0x6c5/0x8d7
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&mm->mmap_sem){++++}:
[...]
__lock_acquire+0x12ab/0x139f
lock_acquire+0x155/0x18e
down_write+0x3f/0x98
flush_old_exec+0x748/0x8d7
load_elf_binary+0x2ca/0xddb
[...]
-> #0 (&(&p->alloc_lock)->rlock){+.+.}:
[...]
__lock_acquire+0x12ab/0x139f
lock_acquire+0x155/0x18e
_raw_spin_lock+0x30/0x83
flush_old_exec+0x703/0x8d7
load_elf_binary+0x2ca/0xddb
[...]
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&mm->mmap_sem);
lock(&(&p->alloc_lock)->rlock);
lock(&mm->mmap_sem);
lock(&(&p->alloc_lock)->rlock);
*** DEADLOCK ***
2 locks held by inside.sh/366:
#0: (____ptrval____) (&sig->cred_guard_mutex){+.+.}, at: __do_execve_file+0x12d/0x869
#1: (____ptrval____) (&mm->mmap_sem){++++}, at: flush_old_exec+0x6c5/0x8d7
stack backtrace:
CPU: 0 PID: 366 Comm: inside.sh Not tainted 5.1.0-10252-gb00152307319-dirty #121
Stack:
[...]
Call Trace:
[<600420de>] show_stack+0x13b/0x155
[<6048906b>] dump_stack+0x2a/0x2c
[<6009ae64>] print_circular_bug+0x332/0x343
[<6009c5c6>] check_prev_add+0x669/0xdad
[<600a06b4>] __lock_acquire+0x12ab/0x139f
[<6009f3d0>] lock_acquire+0x155/0x18e
[<604a07e0>] _raw_spin_lock+0x30/0x83
[<60151e6a>] flush_old_exec+0x703/0x8d7
[<601a8eb8>] load_elf_binary+0x2ca/0xddb
[...]
I think it's because in exec_mmap() we have
down_read(&old_mm->mmap_sem);
...
task_lock(tsk);
...
activate_mm(active_mm, mm);
(which does down_write(&mm->mmap_sem))
I'm not really sure why lockdep throws in the whole knowledge
about the task lock, but it seems that old_mm and mm shouldn't
ever be the same (and it doesn't deadlock) so tell lockdep that
they're different.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
There are some unused functions, and some others that have
unused arguments; clean up the timer code a bit.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
os_timer_one_shot() gets passed a value "unsigned long delta",
so must not have an "int ticks" as that actually ends up being
-1, and thus triggering a timer over and over again.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0
Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull core fixes from Ingo Molnar:
"This fixes a particularly thorny munmap() bug with MPX, plus fixes a
host build environment assumption in objtool"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Allow AR to be overridden with HOSTAR
x86/mpx, mm/core: Fix recursive munmap() corruption
- Kconfig cleanups
- Fix cpu_all_mask() usage
- Various bug fixes
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Merge tag 'for-linus-5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger:
- Kconfig cleanups
- Fix cpu_all_mask() usage
- Various bug fixes
* tag 'for-linus-5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/rw/uml:
um: irq: don't set the chip for all irqs
um: define set_pte_at() as a static inline function, not a macro
um: remove uses of variable length arrays
um: remove unused variable
uml: fix a boot splat wrt use of cpu_all_mask
um: Do not unlock mutex that is not hold.
hostfs: fix mismatch between link_file definition and declaration
arch: um: drivers: Kconfig: pedantic formatting
arch: um: Kconfig: pedantic indention cleanups
um: Revert to using stack for pt_regs in signal handling
This is a bit of a mess, to put it mildly. But, it's a bug
that only seems to have showed up in 4.20 but wasn't noticed
until now, because nobody uses MPX.
MPX has the arch_unmap() hook inside of munmap() because MPX
uses bounds tables that protect other areas of memory. When
memory is unmapped, there is also a need to unmap the MPX
bounds tables. Barring this, unused bounds tables can eat 80%
of the address space.
But, the recursive do_munmap() that gets called vi arch_unmap()
wreaks havoc with __do_munmap()'s state. It can result in
freeing populated page tables, accessing bogus VMA state,
double-freed VMAs and more.
See the "long story" further below for the gory details.
To fix this, call arch_unmap() before __do_unmap() has a chance
to do anything meaningful. Also, remove the 'vma' argument
and force the MPX code to do its own, independent VMA lookup.
== UML / unicore32 impact ==
Remove unused 'vma' argument to arch_unmap(). No functional
change.
I compile tested this on UML but not unicore32.
== powerpc impact ==
powerpc uses arch_unmap() well to watch for munmap() on the
VDSO and zeroes out 'current->mm->context.vdso_base'. Moving
arch_unmap() makes this happen earlier in __do_munmap(). But,
'vdso_base' seems to only be used in perf and in the signal
delivery that happens near the return to userspace. I can not
find any likely impact to powerpc, other than the zeroing
happening a little earlier.
powerpc does not use the 'vma' argument and is unaffected by
its removal.
I compile-tested a 64-bit powerpc defconfig.
== x86 impact ==
For the common success case this is functionally identical to
what was there before. For the munmap() failure case, it's
possible that some MPX tables will be zapped for memory that
continues to be in use. But, this is an extraordinarily
unlikely scenario and the harm would be that MPX provides no
protection since the bounds table got reset (zeroed).
I can't imagine anyone doing this:
ptr = mmap();
// use ptr
ret = munmap(ptr);
if (ret)
// oh, there was an error, I'll
// keep using ptr.
Because if you're doing munmap(), you are *done* with the
memory. There's probably no good data in there _anyway_.
This passes the original reproducer from Richard Biener as
well as the existing mpx selftests/.
The long story:
munmap() has a couple of pieces:
1. Find the affected VMA(s)
2. Split the start/end one(s) if neceesary
3. Pull the VMAs out of the rbtree
4. Actually zap the memory via unmap_region(), including
freeing page tables (or queueing them to be freed).
5. Fix up some of the accounting (like fput()) and actually
free the VMA itself.
This specific ordering was actually introduced by:
dd2283f260 ("mm: mmap: zap pages with read mmap_sem in munmap")
during the 4.20 merge window. The previous __do_munmap() code
was actually safe because the only thing after arch_unmap() was
remove_vma_list(). arch_unmap() could not see 'vma' in the
rbtree because it was detached, so it is not even capable of
doing operations unsafe for remove_vma_list()'s use of 'vma'.
Richard Biener reported a test that shows this in dmesg:
[1216548.787498] BUG: Bad rss-counter state mm:0000000017ce560b idx:1 val:551
[1216548.787500] BUG: non-zero pgtables_bytes on freeing mm: 24576
What triggered this was the recursive do_munmap() called via
arch_unmap(). It was freeing page tables that has not been
properly zapped.
But, the problem was bigger than this. For one, arch_unmap()
can free VMAs. But, the calling __do_munmap() has variables
that *point* to VMAs and obviously can't handle them just
getting freed while the pointer is still in use.
I tried a couple of things here. First, I tried to fix the page
table freeing problem in isolation, but I then found the VMA
issue. I also tried having the MPX code return a flag if it
modified the rbtree which would force __do_munmap() to re-walk
to restart. That spiralled out of control in complexity pretty
fast.
Just moving arch_unmap() and accepting that the bonkers failure
case might eat some bounds tables seems like the simplest viable
fix.
This was also reported in the following kernel bugzilla entry:
https://bugzilla.kernel.org/show_bug.cgi?id=203123
There are some reports that this commit triggered this bug:
dd2283f260 ("mm: mmap: zap pages with read mmap_sem in munmap")
While that commit certainly made the issues easier to hit, I believe
the fundamental issue has been with us as long as MPX itself, thus
the Fixes: tag below is for one of the original MPX commits.
[ mingo: Minor edits to the changelog and the patch. ]
Reported-by: Richard Biener <rguenther@suse.de>
Reported-by: H.J. Lu <hjl.tools@gmail.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Yang Shi <yang.shi@linux.alibaba.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rik van Riel <riel@surriel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-um@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: stable@vger.kernel.org
Fixes: dd2283f260 ("mm: mmap: zap pages with read mmap_sem in munmap")
Link: http://lkml.kernel.org/r/20190419194747.5E1AD6DC@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When defined as macro, the mm argument is unused and subsequently the
variable passed as mm is considered unused by the compiler. This fixes
a build warning.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Acked-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Remove mmiowb() from the kernel memory barrier API and instead, for
architectures that need it, hide the barrier inside spin_unlock() when
MMIO has been performed inside the critical section.
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Merge tag 'arm64-mmiowb' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull mmiowb removal from Will Deacon:
"Remove Mysterious Macro Intended to Obscure Weird Behaviours (mmiowb())
Remove mmiowb() from the kernel memory barrier API and instead, for
architectures that need it, hide the barrier inside spin_unlock() when
MMIO has been performed inside the critical section.
The only relatively recent changes have been addressing review
comments on the documentation, which is in a much better shape thanks
to the efforts of Ben and Ingo.
I was initially planning to split this into two pull requests so that
you could run the coccinelle script yourself, however it's been plain
sailing in linux-next so I've just included the whole lot here to keep
things simple"
* tag 'arm64-mmiowb' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (23 commits)
docs/memory-barriers.txt: Update I/O section to be clearer about CPU vs thread
docs/memory-barriers.txt: Fix style, spacing and grammar in I/O section
arch: Remove dummy mmiowb() definitions from arch code
net/ethernet/silan/sc92031: Remove stale comment about mmiowb()
i40iw: Redefine i40iw_mmiowb() to do nothing
scsi/qla1280: Remove stale comment about mmiowb()
drivers: Remove explicit invocations of mmiowb()
drivers: Remove useless trailing comments from mmiowb() invocations
Documentation: Kill all references to mmiowb()
riscv/mmiowb: Hook up mmwiob() implementation to asm-generic code
powerpc/mmiowb: Hook up mmwiob() implementation to asm-generic code
ia64/mmiowb: Add unconditional mmiowb() to arch_spin_unlock()
mips/mmiowb: Add unconditional mmiowb() to arch_spin_unlock()
sh/mmiowb: Add unconditional mmiowb() to arch_spin_unlock()
m68k/io: Remove useless definition of mmiowb()
nds32/io: Remove useless definition of mmiowb()
x86/io: Remove useless definition of mmiowb()
arm64/io: Remove useless definition of mmiowb()
ARM/io: Remove useless definition of mmiowb()
mmiowb: Hook up mmiowb helpers to spinlocks and generic I/O accessors
...
Pull unified TLB flushing from Ingo Molnar:
"This contains the generic mmu_gather feature from Peter Zijlstra,
which is an all-arch unification of TLB flushing APIs, via the
following (broad) steps:
- enhance the <asm-generic/tlb.h> APIs to cover more arch details
- convert most TLB flushing arch implementations to the generic
<asm-generic/tlb.h> APIs.
- remove leftovers of per arch implementations
After this series every single architecture makes use of the unified
TLB flushing APIs"
* 'core-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
mm/resource: Use resource_overlaps() to simplify region_intersects()
ia64/tlb: Eradicate tlb_migrate_finish() callback
asm-generic/tlb: Remove tlb_table_flush()
asm-generic/tlb: Remove tlb_flush_mmu_free()
asm-generic/tlb: Remove CONFIG_HAVE_GENERIC_MMU_GATHER
asm-generic/tlb: Remove arch_tlb*_mmu()
s390/tlb: Convert to generic mmu_gather
asm-generic/tlb: Introduce CONFIG_HAVE_MMU_GATHER_NO_GATHER=y
arch/tlb: Clean up simple architectures
um/tlb: Convert to generic mmu_gather
sh/tlb: Convert SH to generic mmu_gather
ia64/tlb: Convert to generic mmu_gather
arm/tlb: Convert to generic mmu_gather
asm-generic/tlb, arch: Invert CONFIG_HAVE_RCU_TABLE_INVALIDATE
asm-generic/tlb, ia64: Conditionally provide tlb_migrate_finish()
asm-generic/tlb: Provide generic tlb_flush() based on flush_tlb_mm()
asm-generic/tlb, arch: Provide generic tlb_flush() based on flush_tlb_range()
asm-generic/tlb, arch: Provide generic VIPT cache flush
asm-generic/tlb, arch: Provide CONFIG_HAVE_MMU_GATHER_PAGE_SIZE
asm-generic/tlb: Provide a comment
Hook up asm-generic/mmiowb.h to Kbuild for all architectures so that we
can subsequently include asm/mmiowb.h from core code.
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Generic mmu_gather provides the simple flush_tlb_range() based range
tracking mmu_gather UM needs.
No change in behavior intended.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Move the mmu_gather::page_size things into the generic code instead of
PowerPC specific bits.
No change in behavior intended.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We're (finally) phasing out a.out support for good. As Borislav Petkov
points out, we've supported ELF binaries for about 25 years by now, and
coredumping in particular has bitrotted over the years.
None of the tool chains even support generating a.out binaries any more,
and the plan is to deprecate a.out support entirely for the kernel. But
I want to start with just removing the core dumping code, because I can
still imagine that somebody actually might want to support a.out as a
simpler biinary format.
Particularly if you generate some random binaries on the fly, ELF is a
much more complicated format (admittedly ELF also does have a lot of
toolchain support, mitigating that complexity a lot and you really
should have moved over in the last 25 years).
So it's at least somewhat possible that somebody out there has some
workflow that still involves generating and running a.out executables.
In contrast, it's very unlikely that anybody depends on debugging any
legacy a.out core files. But regardless, I want this phase-out to be
done in two steps, so that we can resurrect a.out support (if needed)
without having to resurrect the core file dumping that is almost
certainly not needed.
Jann Horn pointed to the <asm/a.out-core.h> file that my first trivial
cut at this had missed.
And Alan Cox points out that the a.out binary loader _could_ be done in
user space if somebody wants to, but we might keep just the loader in
the kernel if somebody really wants it, since the loader isn't that big
and has no really odd special cases like the core dumping does.
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc: Jann Horn <jannh@google.com>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "Add support for fast mremap".
This series speeds up the mremap(2) syscall by copying page tables at
the PMD level even for non-THP systems. There is concern that the extra
'address' argument that mremap passes to pte_alloc may do something
subtle architecture related in the future that may make the scheme not
work. Also we find that there is no point in passing the 'address' to
pte_alloc since its unused. This patch therefore removes this argument
tree-wide resulting in a nice negative diff as well. Also ensuring
along the way that the enabled architectures do not do anything funky
with the 'address' argument that goes unnoticed by the optimization.
Build and boot tested on x86-64. Build tested on arm64. The config
enablement patch for arm64 will be posted in the future after more
testing.
The changes were obtained by applying the following Coccinelle script.
(thanks Julia for answering all Coccinelle questions!).
Following fix ups were done manually:
* Removal of address argument from pte_fragment_alloc
* Removal of pte_alloc_one_fast definitions from m68k and microblaze.
// Options: --include-headers --no-includes
// Note: I split the 'identifier fn' line, so if you are manually
// running it, please unsplit it so it runs for you.
virtual patch
@pte_alloc_func_def depends on patch exists@
identifier E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
type T2;
@@
fn(...
- , T2 E2
)
{ ... }
@pte_alloc_func_proto_noarg depends on patch exists@
type T1, T2, T3, T4;
identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@
(
- T3 fn(T1, T2);
+ T3 fn(T1);
|
- T3 fn(T1, T2, T4);
+ T3 fn(T1, T2);
)
@pte_alloc_func_proto depends on patch exists@
identifier E1, E2, E4;
type T1, T2, T3, T4;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@
(
- T3 fn(T1 E1, T2 E2);
+ T3 fn(T1 E1);
|
- T3 fn(T1 E1, T2 E2, T4 E4);
+ T3 fn(T1 E1, T2 E2);
)
@pte_alloc_func_call depends on patch exists@
expression E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@
fn(...
-, E2
)
@pte_alloc_macro depends on patch exists@
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
identifier a, b, c;
expression e;
position p;
@@
(
- #define fn(a, b, c) e
+ #define fn(a, b) e
|
- #define fn(a, b) e
+ #define fn(a) e
)
Link: http://lkml.kernel.org/r/20181108181201.88826-2-joelaf@google.com
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Suggested-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
reenable_fd has been a NOP since the introduction of the EPOLL
based interrupt controller.
reenable_channel() is no longer needed as the flow control is
now handled via the write IRQs on the channel.
Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This commit removes redundant generic-y defines in
arch/um/include/asm/Kbuild.
It is redundant to define generic-y when arch-specific implementation
exists in arch/$(ARCH)/include/asm/*.h
Remove the following generic-y:
hardirq.h
io.h
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Changing protection is a very high cost operation in UML
because in addition to an extra syscall it also interrupts
mmap merge sequences generated by the tlb.
While the condition is not particularly common it is worth
avoiding.
Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Support for DISCARD and WRITE_ZEROES in the ubd driver using
fallocate.
DISCARD is enabled by default and can be disabled using a new
UBD command line flag.
If the underlying fs on which the UBD image is stored does not
support DISCARD the support for both DISCARD and WRITE_ZEROES
is turned off.
Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Pull UML updates from Richard Weinberger:
- removal of old and dead code
- a bug fix for our tty driver
- other minor cleanups across the code base
* 'for-linus-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
um: Make line/tty semantics use true write IRQ
um: trap: fix spelling mistake, EACCESS -> EACCES
um: Don't hardcode path as it is architecture dependent
um: NULL check before kfree is not needed
um: remove unused AIO code
um: Give start_idle_thread() a return code
um: Remove update_debugregs()
um: Drop own definition of PTRACE_SYSEMU/_SINGLESTEP
Since the struct lsm_info table is not an initcall, we can just move it
into INIT_DATA like all the other tables.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: James Morris <james.morris@microsoft.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
Pull uml updates from Richard Weinberger:
"Minor updates for UML:
- fixes for our new vector network driver by Anton
- initcall cleanup by Alexander
- We have a new mailinglist, sourceforge.net sucks"
* 'for-linus-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
um: Fix raw interface options
um: Fix initialization of vector queues
um: remove uml initcalls
um: Update mailing list address
__uml_initcall() is not used and .uml.initcall.init section is empty:
$ grep -r '__uml_initcall('
arch/um/include/shared/init.h:#define __uml_initcall(fn) \
$ readelf -s ../umobj/linux | grep __uml_initcall
23214: 00000000603b75d8 0 NOTYPE GLOBAL DEFAULT 32 __uml_initcall_start
25337: 00000000603b75d8 0 NOTYPE GLOBAL DEFAULT 32 __uml_initcall_end
So it is unnecessary.
Signed-off-by: Alexander Pateenok <pateenoc@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
We have a couple of files that try to include asm/compat.h on
architectures where this is available. Those should generally use the
higher-level linux/compat.h file, but that in turn fails to include
asm/compat.h when CONFIG_COMPAT is disabled, unless we can provide
that header on all architectures.
This adds the asm/compat.h for all remaining architectures to
simplify the dependencies.
Architectures that are getting removed in linux-4.17 are not changed
here, to avoid needless conflicts with the removal patches. Those
architectures are broken by this patch, but we have already shown
that they have no users.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
1. Provides infrastructure for vector IO using recvmmsg/sendmmsg.
1.1. Multi-message read.
1.2. Multi-message write.
1.3. Optimized queue support for multi-packet enqueue/dequeue.
1.4. BQL/DQL support.
2. Implements transports for several transports as well support
for direct wiring of PWEs to NIC. Allows direct connection of VMs
to host, other VMs and network devices with no switch in use.
2.1. Raw socket >4 times higher PPS and 10 times higher tcp RX
than existing pcap based transport (> 4Gbit)
2.2. New tap transport using socket RX and tap xmit. Similar
performance improvements (>4Gbit)
2.3. GRE transport - direct wiring to GRE PWE
2.4. L2TPv3 transport - direct wiring to L2TPv3 PWE
3. Tuning, performance and offload related setting support via ethtool.
4. Initial BPF support - used in tap/raw to avoid software looping
5. Scatter Gather support.
6. VNET and checksum offload support for raw socket transport.
7. TSO/GSO support where applicable or available
8. Migrates all error messages to netdevice_*() and rate limits
them where needed.
Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
1. Removes the need to walk the IRQ/Device list to determine
who triggered the IRQ.
2. Improves scalability (up to several times performance
improvement for cases with 10s of devices).
3. Improves UML baseline IO performance for one disk + one NIC
use case by up to 10%.
4. Introduces write poll triggered IRQs.
5. Prerequisite for introducing high performance mmesg family
of functions in network IO.
6. Fixes RNG shutdown which was leaking a file descriptor
Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
