From fb30d64568fd8f6a21afef987f11852a109723da Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Tue, 18 Apr 2006 22:21:44 -0700 Subject: [PATCH] [PATCH] uml: add missing __volatile__ We were missing __volatile__ on some bits of asm in the segfault handlers. On x86_64, this was messing up the move from %rdx to uc because that was moved to after the GET_FAULTINFO_FROM_SC, which changed %rdx. Also changed the other bit of asm and the one in the i386 handler to prevent any similar occurrences. Signed-off-by: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/sys-i386/stub_segv.c | 4 ++-- arch/um/sys-x86_64/stub_segv.c | 10 +++++----- 2 files changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/um/sys-i386/stub_segv.c b/arch/um/sys-i386/stub_segv.c index a37f672ec964..2355dc19c46c 100644 --- a/arch/um/sys-i386/stub_segv.c +++ b/arch/um/sys-i386/stub_segv.c @@ -27,6 +27,6 @@ stub_segv_handler(int sig) * the stack in its original form when we do the sigreturn here, by * hand. */ - __asm__("mov %0,%%esp ; movl %1, %%eax ; " - "int $0x80" : : "a" (sc), "g" (__NR_sigreturn)); + __asm__ __volatile__("mov %0,%%esp ; movl %1, %%eax ; " + "int $0x80" : : "a" (sc), "g" (__NR_sigreturn)); } diff --git a/arch/um/sys-x86_64/stub_segv.c b/arch/um/sys-x86_64/stub_segv.c index a27099533198..1c967026c957 100644 --- a/arch/um/sys-x86_64/stub_segv.c +++ b/arch/um/sys-x86_64/stub_segv.c @@ -33,7 +33,7 @@ stub_segv_handler(int sig) struct ucontext *uc; int pid; - __asm__("movq %%rdx, %0" : "=g" (uc) :); + __asm__ __volatile__("movq %%rdx, %0" : "=g" (uc) :); GET_FAULTINFO_FROM_SC(*((struct faultinfo *) UML_CONFIG_STUB_DATA), &uc->uc_mcontext); @@ -44,8 +44,8 @@ stub_segv_handler(int sig) * the signal frame. So, we use the ucontext pointer, which we know * already, to get the signal frame pointer, and add 8 to that. */ - __asm__("movq %0, %%rsp; movq %1, %%rax ; syscall": : - "g" ((unsigned long) container_of(uc, struct rt_sigframe, - uc) + 8), - "g" (__NR_rt_sigreturn)); + __asm__ __volatile__("movq %0, %%rsp; movq %1, %%rax ; syscall": : + "g" ((unsigned long) + container_of(uc, struct rt_sigframe, uc) + 8), + "g" (__NR_rt_sigreturn)); }