On Fri, Jan 18, 2019 at 9:07 PM tedheadster <tedheads...@gmail.com> wrote: > > I do not see this problem with the upstream kernel, so 3.16 probably > needs a missing upstream patch.
This was indeed fixed by Andy Lutomirski's follow-up patch "x86/vdso: Fix vDSO syscall fallback asm constraint regression". I tested part of Andy's patch and it resolved the failure. The 3.16 LTS kernel does not have the tools/testing/selftests/x86/test_vdso.c code, so a partial patch is indicated, unless Andy wants to provide that. Kindly backport to 3.16 LTS series. reported-by: Matthew Whitehead <tedheads...@gmail.com> tested-by: Matthew Whitehead <tedheads...@gmail.com> --- arch/x86/vdso/vclock_gettime.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c index 00b5ea4..a3d5326 100644 --- a/arch/x86/vdso/vclock_gettime.c +++ b/arch/x86/vdso/vclock_gettime.c @@ -147,11 +147,11 @@ notrace static long vdso_fallback_gettime(long clock, struct timespec *ts) 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; } @@ -162,11 +162,11 @@ notrace static long vdso_fallback_gtod(struct timeval *tv, struct timezone *tz) 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; } -- 1.8.3.1