Pull uaccess unification updates from Al Viro:
"This is the uaccess unification pile. It's _not_ the end of uaccess
work, but the next batch of that will go into the next cycle. This one
mostly takes copy_from_user() and friends out of arch/* and gets the
zero-padding behaviour in sync for all architectures.
Dealing with the nocache/writethrough mess is for the next cycle;
fortunately, that's x86-only. Same for cleanups in iov_iter.c (I am
sold on access_ok() in there, BTW; just not in this pile), same for
reducing __copy_... callsites, strn*... stuff, etc. - there will be a
pile about as large as this one in the next merge window.
This one sat in -next for weeks. -3KLoC"
* 'work.uaccess' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (96 commits)
HAVE_ARCH_HARDENED_USERCOPY is unconditional now
CONFIG_ARCH_HAS_RAW_COPY_USER is unconditional now
m32r: switch to RAW_COPY_USER
hexagon: switch to RAW_COPY_USER
microblaze: switch to RAW_COPY_USER
get rid of padding, switch to RAW_COPY_USER
ia64: get rid of copy_in_user()
ia64: sanitize __access_ok()
ia64: get rid of 'segment' argument of __do_{get,put}_user()
ia64: get rid of 'segment' argument of __{get,put}_user_check()
ia64: add extable.h
powerpc: get rid of zeroing, switch to RAW_COPY_USER
esas2r: don't open-code memdup_user()
alpha: fix stack smashing in old_adjtimex(2)
don't open-code kernel_setsockopt()
mips: switch to RAW_COPY_USER
mips: get rid of tail-zeroing in primitives
mips: make copy_from_user() zero tail explicitly
mips: clean and reorder the forest of macros...
mips: consolidate __invoke_... wrappers
...
The patch 554bfeceb8 ("parisc: Fix access
fault handling in pa_memcpy()") reimplements the pa_memcpy function.
Unfortunatelly, it makes the kernel unbootable. The crash happens in the
function ide_complete_cmd where memcpy is called with the same source
and destination address.
This patch fixes a few bugs in pa_memcpy:
* When jumping to .Lcopy_loop_16 for the first time, don't skip the
instruction "ldi 31,t0" (this bug made the kernel unbootable)
* Use the COND macro when comparing length, so that the comparison is
64-bit (a theoretical issue, in case the length is greater than
0xffffffff)
* Don't use the COND macro after the "extru" instruction (the PA-RISC
specification says that the upper 32-bits of extru result are undefined,
although they are set to zero in practice)
* Fix exception addresses in .Lcopy16_fault and .Lcopy8_fault
* Rename .Lcopy_loop_4 to .Lcopy_loop_8 (so that it is consistent with
.Lcopy8_fault)
Cc: <stable@vger.kernel.org> # v4.9+
Fixes: 554bfeceb8 ("parisc: Fix access fault handling in pa_memcpy()")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Al Viro noticed that userspace accesses via get_user()/put_user() can be
simplified a lot with regard to usage of the exception handling.
This patch implements a fixup routine for get_user() and put_user() in such
that the exception handler will automatically load -EFAULT into the register
%r8 (the error value) in case on a fault on userspace. Additionally the fixup
routine will zero the target register on fault in case of a get_user() call.
The target register is extracted out of the faulting assembly instruction.
This patch brings a few benefits over the old implementation:
1. Exception handling gets much cleaner, easier and smaller in size.
2. Helper functions like fixup_get_user_skip_1 (all of fixup.S) can be dropped.
3. No need to hardcode %r9 as target register for get_user() any longer. This
helps the compiler register allocator and thus creates less assembler
statements.
4. No dependency on the exception_data contents any longer.
5. Nested faults will be handled cleanly.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Cc: <stable@vger.kernel.org> # v4.9+
Signed-off-by: Helge Deller <deller@gmx.de>
pa_memcpy() is the major memcpy implementation in the parisc kernel which is
used to do any kind of userspace/kernel memory copies.
Al Viro noticed various bugs in the implementation of pa_mempcy(), most notably
that in case of faults it may report back to have copied more bytes than it
actually did.
Fixing those bugs is quite hard in the C-implementation, because the compiler
is messing around with the registers and we are not guaranteed that specific
variables are always in the same processor registers. This makes proper fault
handling complicated.
This patch implements pa_memcpy() in assembler. That way we have correct fault
handling and adding a 64-bit copy routine was quite easy.
Runtime tested with 32- and 64bit kernels.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Cc: <stable@vger.kernel.org> # v4.9+
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace the in order struct initialisation style with explicit field
style.
Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Add a native implementation for the sched_clock() function which utilizes the
processor-internal cycle counter (Control Register 16) as high-resolution time
source.
With this patch we now get much more fine-grained resolutions in various
in-kernel time measurements (e.g. when viewing the function tracing logs), and
probably a more accurate scheduling on SMP systems.
There are a few specific implementation details in this patch:
1. On a 32bit kernel we emulate the higher 32bits of the required 64-bit
resolution of sched_clock() by increasing a per-cpu counter at every
wrap-around of the 32bit cycle counter.
2. In a SMP system, the cycle counters of the various CPUs are not syncronized
(similiar to the TSC in a x86_64 system). To cope with this we define
HAVE_UNSTABLE_SCHED_CLOCK and let the upper layers do the adjustment work.
3. Since we need HAVE_UNSTABLE_SCHED_CLOCK, we need to provide a cmpxchg64()
function even on a 32-bit kernel.
4. A 64-bit SMP kernel which is started on a UP system will mark the
sched_clock() implementation as "stable", which means that we don't expect any
jumps in the returned counter. This is true because we then run only on one
CPU.
Signed-off-by: Helge Deller <deller@gmx.de>
Handling exceptions from modules never worked on parisc.
It was just masked by the fact that exceptions from modules
don't happen during normal use.
When a module triggers an exception in get_user() we need to load the
main kernel dp value before accessing the exception_data structure, and
afterwards restore the original dp value of the module on exit.
Noticed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Convert to the use of this_cpu_ptr().
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Helge Deller <deller@gmx.de>
gcc (4.8.x) creates wrong code when the pa_memcpy() functions are
inlined. Especially in 32bit builds it calculates wrong return values
if we encounter a fault during execution of the memcpy.
Signed-off-by: Helge Deller <deller@gmx.de>
Each CPU has it's own Control Register 16 (CR16) which is used as time source
for the udelay() function. But since the CR16 registers across different CPUs
are not synced, we need to recalculate the loop count if we get switched away
to ensure that we really delay as much time as requested.
Signed-off-by: Helge Deller <deller@gmx.de>
Provide a macro ASM_EXCEPTIONTABLE_ENTRY() to create exception table
entries and convert all open-coded places to use that macro.
This patch is a first step toward creating a exception table which only
holds 32bit pointers even on a 64bit kernel. That way in my own kernel
I was able to reduce the in-kernel exception table from 44kB to 22kB.
Signed-off-by: Helge Deller <deller@gmx.de>
When running the LTP testsuite one may hit this kernel BUG() with the
write06 testcase:
kernel BUG at mm/filemap.c:2023!
CPU: 1 PID: 8614 Comm: writev01 Not tainted 3.10.0-rc7-64bit-c3000+ #6
IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000401e6e84 00000000401e6e88
IIR: 03ffe01f ISR: 0000000010340000 IOR: 000001fbe0380820
CPU: 1 CR30: 00000000bef80000 CR31: ffffffffffffffff
ORIG_R28: 00000000bdc192c0
IAOQ[0]: iov_iter_advance+0x3c/0xc0
IAOQ[1]: iov_iter_advance+0x40/0xc0
RP(r2): generic_file_buffered_write+0x204/0x3f0
Backtrace:
[<00000000401e764c>] generic_file_buffered_write+0x204/0x3f0
[<00000000401eab24>] __generic_file_aio_write+0x244/0x448
[<00000000401eadc0>] generic_file_aio_write+0x98/0x150
[<000000004024f460>] do_sync_readv_writev+0xc0/0x130
[<000000004025037c>] compat_do_readv_writev+0x12c/0x340
[<00000000402505f8>] compat_writev+0x68/0xa0
[<0000000040251d88>] compat_SyS_writev+0x98/0xf8
Reason for this crash is a gcc miscompilation in the fault handlers of
pa_memcpy() which return the fault address instead of the copied bytes.
Since this seems to be a generic problem with gcc-4.7.x (and below), it's
better to simplify the fault handlers in pa_memcpy to avoid this problem.
Here is a simple reproducer for the problem:
int main(int argc, char **argv)
{
int fd, nbytes;
struct iovec wr_iovec[] = {
{ "TEST STRING ",32},
{ (char*)0x40005000,32} }; // random memory.
fd = open(DATA_FILE, O_RDWR | O_CREAT, 0666);
nbytes = writev(fd, wr_iovec, 2);
printf("return value = %d, errno %d (%s)\n",
nbytes, errno, strerror(errno));
return 0;
}
In addition, John David Anglin wrote:
There is no gcc PR as pa_memcpy is not legitimate C code. There is an
implicit assumption that certain variables will contain correct values
when an exception occurs and the code randomly jumps to one of the
exception blocks. There is no guarantee of this. If a PR was filed, it
would likely be marked as invalid.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: <stable@vger.kernel.org> # 3.8+
Signed-off-by: Helge Deller <deller@gmx.de>
The Debian experimental linux source package (3.8.5-1) build fails
with the following errors:
...
MODPOST 2016 modules
ERROR: "__ucmpdi2" [fs/btrfs/btrfs.ko] undefined!
ERROR: "__ucmpdi2" [drivers/md/dm-verity.ko] undefined!
The attached patch resolves this problem. It is based on the s390
implementation of ucmpdi2.c.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Avoid this warning, while still prevent gcc from optimizing away the exception code:
arch/parisc/lib/memcpy.c: In function ‘pa_memcpy’:
arch/parisc/lib/memcpy.c:256:2: warning: ‘dummy’ may be used uninitialized in this function [-Wuninitialized]
Signed-off-by: Helge Deller <deller@gmx.de>
parisc copied pci_iomap from generic code, probably to avoid
pulling the rest of iomap.c in. Since that's in
a separate file now, we can reuse the common implementation.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add CONFIG_DEBUG_STRICT_USER_COPY_CHECKS, copied from the x86
implementation. Tested with 32 and 64bit kernel.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Further name space cleanup. No functional change
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: linux-arch@vger.kernel.org
The raw_spin* namespace was taken by lockdep for the architecture
specific implementations. raw_spin_* would be the ideal name space for
the spinlocks which are not converted to sleeping locks in preempt-rt.
Linus suggested to convert the raw_ to arch_ locks and cleanup the
name space instead of using an artifical name like core_spin,
atomic_spin or whatever
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: linux-arch@vger.kernel.org
Now that the return from alloc_percpu is compatible with the address
of per-cpu vars, it makes sense to hand around the address of per-cpu
variables. To make this sane, we remove the per_cpu__ prefix we used
created to stop people accidentally using these vars directly.
Now we have sparse, we can use that (next patch).
tj: * Updated to convert stuff which were missed by or added after the
original patch.
* Kill per_cpu_var() macro.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
>>>> I think this is what was intended? Note that this patch may affect
>>>> profiling.
>>> it really should be
>>>
>>> - if (likely(t1 & (sizeof(unsigned int)-1)) == 0) {
>>> + if (likely((t1 & (sizeof(unsigned int)-1)) == 0)) {
>>>
>>> randolph
Reported-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Randolph Chung <tausq@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Make the following needlessly global code static:
- iomap.c: struct iomap_ops[]
- memcpy.c: pa_memcpy()
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
This trivial patch fixes the following section warnings on PARISC:
> WARNING: vmlinux.o (.text.1): unexpected section name.
>The (.[number]+) following section name are ld generated and not expected.
> Did you forget to use "ax"/"aw" in a .S file?
> Note that for example <linux/init.h> contains
> section definitions for use in .S files.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Almost all implementations of pci_iomap() in the kernel, including the generic
lib/iomap.c one, copies the content of a struct resource into unsigned long's
which will break on 32 bits platforms with 64 bits resources.
This fixes all definitions of pci_iomap() to use resource_size_t. I also
"fixed" the 64bits arch for consistency.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit efb80e7e09, it turned
out to cause sporadic problems with the timer interrupt on 32-bit kernels.
Needs more investigation.
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Currently we're hacking libs-y to include libgcc.a, but this has
unforeseen consequences since the userspace libgcc is linked with fpregs
enabled. We need the kernel to stop using fpregs in an uncontrolled manner
to implement lazy fpu state saves.
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
"extern inline" will have different semantics with gcc 4.3, and "static
inline" is correct here.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Matthew Wilcox <willy@debian.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
- this macro unifies the code to add exception table entries
- additionally use ENTRY()/ENDPROC() at more places
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
* sanitized prototypes, annotated
* kill shift-by-16 in checksum calculation
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove CONFIG_DEBUG_IOREMAP, it's now obsolete and won't work anyway.
Remove it from lib/KConfig since it was only available on parisc.
Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
fixup.S needs to specify .level and use correct LDREG macro.
New binutils has a bug where it doesn't "promote" from PA1.0 to PA1.1
correctly when using ",s" completer.
remove use of __LP64__ in assembly.h and add some white space.
Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
Disable use of fpregs in pa_memcpy, and turn on the
-mdisable-fpregs flag.
Signed-off-by: Randolph Chung <tausq@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
