| From 02e425668f5c9deb42787d10001a3b605993ad15 Mon Sep 17 00:00:00 2001 |
| From: Andy Lutomirski <luto@kernel.org> |
| Date: Wed, 3 Oct 2018 16:23:49 -0700 |
| Subject: x86/vdso: Fix vDSO syscall fallback asm constraint regression |
| |
| From: Andy Lutomirski <luto@kernel.org> |
| |
| commit 02e425668f5c9deb42787d10001a3b605993ad15 upstream. |
| |
| When I added the missing memory outputs, I failed to update the |
| index of the first argument (ebx) on 32-bit builds, which broke the |
| fallbacks. Somehow I must have screwed up my testing or gotten |
| lucky. |
| |
| Add another test to cover gettimeofday() as well. |
| |
| Signed-off-by: Andy Lutomirski <luto@kernel.org> |
| Cc: Linus Torvalds <torvalds@linux-foundation.org> |
| Cc: Peter Zijlstra <peterz@infradead.org> |
| Cc: Thomas Gleixner <tglx@linutronix.de> |
| Cc: stable@vger.kernel.org |
| Fixes: 715bd9d12f84 ("x86/vdso: Fix asm constraints on vDSO syscall fallbacks") |
| Link: http://lkml.kernel.org/r/21bd45ab04b6d838278fa5bebfa9163eceffa13c.1538608971.git.luto@kernel.org |
| Signed-off-by: Ingo Molnar <mingo@kernel.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| arch/x86/entry/vdso/vclock_gettime.c | 8 ++++---- |
| 1 file changed, 4 insertions(+), 4 deletions(-) |
| |
| --- a/arch/x86/entry/vdso/vclock_gettime.c |
| +++ b/arch/x86/entry/vdso/vclock_gettime.c |
| @@ -62,11 +62,11 @@ notrace static long vdso_fallback_gettim |
| |
| asm ( |
| "mov %%ebx, %%edx \n" |
| - "mov %2, %%ebx \n" |
| + "mov %[clock], %%ebx \n" |
| "call __kernel_vsyscall \n" |
| "mov %%edx, %%ebx \n" |
| : "=a" (ret), "=m" (*ts) |
| - : "0" (__NR_clock_gettime), "g" (clock), "c" (ts) |
| + : "0" (__NR_clock_gettime), [clock] "g" (clock), "c" (ts) |
| : "memory", "edx"); |
| return ret; |
| } |
| @@ -77,11 +77,11 @@ notrace static long vdso_fallback_gtod(s |
| |
| asm ( |
| "mov %%ebx, %%edx \n" |
| - "mov %2, %%ebx \n" |
| + "mov %[tv], %%ebx \n" |
| "call __kernel_vsyscall \n" |
| "mov %%edx, %%ebx \n" |
| : "=a" (ret), "=m" (*tv), "=m" (*tz) |
| - : "0" (__NR_gettimeofday), "g" (tv), "c" (tz) |
| + : "0" (__NR_gettimeofday), [tv] "g" (tv), "c" (tz) |
| : "memory", "edx"); |
| return ret; |
| } |
