kernel/git/stable/linux.git/arch/x86/lib, branch linux-3.5.y

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2012-06-29T17:29:54+00:00

Pull x86 fixes from Ingo Molnar. * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, cpufeature: Remove stray %s, add -w to mkcapflags.pl x86, cpufeature: Catch duplicate CPU feature strings x86, cpufeature: Rename X86_FEATURE_DTS to X86_FEATURE_DTHERM x86: Fix kernel-doc warnings x86, compat: Use test_thread_flag(TIF_IA32) in compat signal delivery

x86: Fix kernel-doc warnings

2012-06-18T08:53:18+00:00

Signed-off-by: Wanpeng Li Cc: Peter Zijlstra Cc: Jason Wessel Cc: Jan Kiszka Cc: Gavin Shan Cc: Wanpeng Li Signed-off-by: Ingo Molnar

perf/x86: Fix broken LBR fixup code

2012-06-13T13:00:28+00:00

I noticed that the LBR fixups were not working anymore on programs where they used to. I tracked this down to a recent change to copy_from_user_nmi(): db0dc75d640 ("perf/x86: Check user address explicitly in copy_from_user_nmi()") This commit added a call to __range_not_ok() to the copy_from_user_nmi() routine. The problem is that the logic of the test must be reversed. __range_not_ok() returns 0 if the range is VALID. We want to return early from copy_from_user_nmi() if the range is NOT valid. Signed-off-by: Stephane Eranian Signed-off-by: Peter Zijlstra Acked-by: Arun Sharma Link: http://lkml.kernel.org/r/20120611134426.GA7542@quad Signed-off-by: Ingo Molnar

perf/x86: Check user address explicitly in copy_from_user_nmi()

2012-06-06T15:08:04+00:00

Signed-off-by: Arun Sharma Cc: Linus Torvalds Cc: linux-kernel@vger.kernel.org Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1334961696-19580-5-git-send-email-asharma@fb.com Signed-off-by: Ingo Molnar

x86/decoder: Fix bsr/bsf/jmpe decoding with operand-size prefix

2012-06-06T06:54:18+00:00

Fix the x86 instruction decoder to decode bsr/bsf/jmpe with operand-size prefix (66h). This fixes the test case failure reported by Linus, attached below. bsf/bsr/jmpe have a special encoding. Opcode map in Intel Software Developers Manual vol2 says they have TZCNT/LZCNT variants if it has F3h prefix. However, there is no information if it has other 66h or F2h prefixes. Current instruction decoder supposes that those are bad instructions, but it actually accepts at least operand-size prefixes. H. Peter Anvin further explains: " TZCNT/LZCNT are F3 + BSF/BSR exactly because the F2 and F3 prefixes have historically been no-ops with most instructions. This allows software to unconditionally use the prefixed versions and get TZCNT/LZCNT on the processors that have them if they don't care about the difference. " This fixes errors reported by test_get_len: Warning: arch/x86/tools/test_get_len found difference at :ffffffff81036d87 Warning: ffffffff81036de5: 66 0f bc c2 bsf %dx,%ax Warning: objdump says 4 bytes, but insn_get_length() says 3 Warning: arch/x86/tools/test_get_len found difference at :ffffffff81036ea6 Warning: ffffffff81036f04: 66 0f bd c2 bsr %dx,%ax Warning: objdump says 4 bytes, but insn_get_length() says 3 Warning: decoded and checked 13298882 instructions with 2 warnings Reported-by: Linus Torvalds Reported-by: Pekka Enberg Signed-off-by: Masami Hiramatsu Cc: "H. Peter Anvin" Cc: Link: http://lkml.kernel.org/r/20120604150911.22338.43296.stgit@localhost.localdomain Signed-off-by: Ingo Molnar

x86: use the new generic strnlen_user() function

2012-05-26T18:33:54+00:00

This throws away the old x86-specific functions in favor of the generic optimized version. Signed-off-by: Linus Torvalds

x86: use generic strncpy_from_user routine

2012-05-26T17:14:39+00:00

The generic strncpy_from_user() is not really optimal, since it is designed to work on both little-endian and big-endian. And on little-endian you can simplify much of the logic to find the first zero byte, since little-endian arithmetic doesn't have to worry about the carry bit propagating into earlier bytes (only later bytes, which we don't care about). But I have patches to make the generic routines use the architecture- specific infrastructure, so that we can regain the little-endian optimizations. But before we do that, switch over to the generic routines to make the patches each do just one well-defined thing. Signed-off-by: Linus Torvalds

Merge branch 'x86-extable-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2012-05-23T17:44:35+00:00

Pull exception table generation updates from Ingo Molnar: "The biggest change here is to allow the build-time sorting of the exception table, to speed up booting. This is achieved by the architecture enabling BUILDTIME_EXTABLE_SORT. This option is enabled for x86 and MIPS currently. On x86 a number of fixes and changes were needed to allow build-time sorting of the exception table, in particular a relocation invariant exception table format was needed. This required the abstracting out of exception table protocol and the removal of 20 years of accumulated assumptions about the x86 exception table format. While at it, this tree also cleans up various other aspects of exception handling, such as early(er) exception handling for rdmsr_safe() et al. All in one, as the result of these changes the x86 exception code is now pretty nice and modern. As an added bonus any regressions in this code will be early and violent crashes, so if you see any of those, you'll know whom to blame!" Fix up trivial conflicts in arch/{mips,x86}/Kconfig files due to nearby modifications of other core architecture options. * 'x86-extable-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits) Revert "x86, extable: Disable presorted exception table for now" scripts/sortextable: Handle relative entries, and other cleanups x86, extable: Switch to relative exception table entries x86, extable: Disable presorted exception table for now x86, extable: Add _ASM_EXTABLE_EX() macro x86, extable: Remove open-coded exception table entries in arch/x86/ia32/ia32entry.S x86, extable: Remove open-coded exception table entries in arch/x86/include/asm/xsave.h x86, extable: Remove open-coded exception table entries in arch/x86/include/asm/kvm_host.h x86, extable: Remove the now-unused __ASM_EX_SEC macros x86, extable: Remove open-coded exception table entries in arch/x86/xen/xen-asm_32.S x86, extable: Remove open-coded exception table entries in arch/x86/um/checksum_32.S x86, extable: Remove open-coded exception table entries in arch/x86/lib/usercopy_32.c x86, extable: Remove open-coded exception table entries in arch/x86/lib/putuser.S x86, extable: Remove open-coded exception table entries in arch/x86/lib/getuser.S x86, extable: Remove open-coded exception table entries in arch/x86/lib/csum-copy_64.S x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_nocache_64.S x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S x86, extable: Remove open-coded exception table entries in arch/x86/lib/checksum_32.S x86, extable: Remove open-coded exception table entries in arch/x86/kernel/test_rodata.c x86, extable: Remove open-coded exception table entries in arch/x86/kernel/entry_64.S ...

x86: make word-at-a-time strncpy_from_user clear bytes at the end

2012-04-28T21:27:38+00:00

This makes the newly optimized x86 strncpy_from_user clear the final bytes in the word past the final NUL character, rather than copy them as the word they were in the source. NOTE! Unlike the silly semantics of the libc 'strncpy()' function, the kernel strncpy_from_user() has never cleared all of the end of the destination buffer. And neither does it do so now: it only clears the bytes at the end of the last word it copied. So why make this change at all? It doesn't really cost us anything extra (we have to calculate the mask to get the length anyway), and it means that *if* any user actually cares about zeroing the whole buffer, they can do a "memset()" before the strncpy_from_user(), and we will no longer write random bytes after the NUL character. In particular, the buffer contents will now at no point contain random source data from beyond the end of the string. In other words, it makes behavior a bit more repeatable at no new cost, so it's a small cleanup. I've been carrying this as a patch for the last few weeks or so in my tree (done at the same time the sign error was fixed in commit 12e993b89464), I might as well commit it. Signed-off-by: Linus Torvalds

x86, extable: Remove open-coded exception table entries in arch/x86/lib/usercopy_32.c

2012-04-20T20:51:39+00:00

Remove open-coded exception table entries in arch/x86/lib/usercopy_32.c, and replace them with _ASM_EXTABLE() macros; this will allow us to change the format and type of the exception table entries. Signed-off-by: H. Peter Anvin Cc: David Daney Link: http://lkml.kernel.org/r/CA%2B55aFyijf43qSu3N9nWHEBwaGbb7T2Oq9A=9EyR=Jtyqfq_cQ@mail.gmail.com