[ Josip, when I hit this I thought that if it were a gcc bug it might explain your gcc-4.4 kernel failures. That's why I haven't played with your machines yet. Now that I know this is actually a kernel bug effecting only user applications, I will go pursue your issues. ] I originally thought this was a gcc bug: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43004 But it's actually a kernel issue. When we clone or create a signal stack we only 8-byte align the stack frame, it should be 16-byte aligned on 64-bit. Use 16-byte alignment for 32-bit too since that's harmless and it's cheaper that way. Distribution folks you really want this in your kernels, otherwise 64-bit threads and signal handlers will have broken alloca() and corrupt their stacks. I'll push this to Linus and -stable. -------------------- sparc: Align clone and signal stacks to 16 bytes. This is mandatory for 64-bit processes, and doing it also for 32-bit processes saves a conditional in the compat case. This fixes the glibc/nptl/tst-stdio1 test case, as well as many others, on 64-bit. Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> --- arch/sparc/kernel/process_32.c | 2 +- arch/sparc/kernel/process_64.c | 8 ++++---- arch/sparc/kernel/signal32.c | 10 ++++++---- arch/sparc/kernel/signal_32.c | 6 ++++-- arch/sparc/kernel/signal_64.c | 8 +++++--- 5 files changed, 20 insertions(+), 14 deletions(-) diff --git a/arch/sparc/kernel/process_32.c b/arch/sparc/kernel/process_32.c index 2830b41..f23c8fd 100644 --- a/arch/sparc/kernel/process_32.c +++ b/arch/sparc/kernel/process_32.c @@ -526,7 +526,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, * Set some valid stack frames to give to the child. */ childstack = (struct sparc_stackf __user *) - (sp & ~0x7UL); + (sp & ~0x15UL); parentstack = (struct sparc_stackf __user *) regs->u_regs[UREG_FP]; diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c index 18d6785..6679eeb 100644 --- a/arch/sparc/kernel/process_64.c +++ b/arch/sparc/kernel/process_64.c @@ -406,11 +406,11 @@ static unsigned long clone_stackframe(unsigned long csp, unsigned long psp) } else __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6])); - /* Now 8-byte align the stack as this is mandatory in the - * Sparc ABI due to how register windows work. This hides - * the restriction from thread libraries etc. -DaveM + /* Now align the stack as this is mandatory in the Sparc ABI + * due to how register windows work. This hides the + * restriction from thread libraries etc. */ - csp &= ~7UL; + csp &= ~15UL; distance = fp - psp; rval = (csp - distance); diff --git a/arch/sparc/kernel/signal32.c b/arch/sparc/kernel/signal32.c index ba5b09a..ea22cd3 100644 --- a/arch/sparc/kernel/signal32.c +++ b/arch/sparc/kernel/signal32.c @@ -120,8 +120,8 @@ struct rt_signal_frame32 { }; /* Align macros */ -#define SF_ALIGNEDSZ (((sizeof(struct signal_frame32) + 7) & (~7))) -#define RT_ALIGNEDSZ (((sizeof(struct rt_signal_frame32) + 7) & (~7))) +#define SF_ALIGNEDSZ (((sizeof(struct signal_frame32) + 15) & (~15))) +#define RT_ALIGNEDSZ (((sizeof(struct rt_signal_frame32) + 15) & (~15))) int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from) { @@ -420,15 +420,17 @@ static void __user *get_sigframe(struct sigaction *sa, struct pt_regs *regs, uns sp = current->sas_ss_sp + current->sas_ss_size; } + sp -= framesize; + /* Always align the stack frame. This handles two cases. First, * sigaltstack need not be mindful of platform specific stack * alignment. Second, if we took this signal because the stack * is not aligned properly, we'd like to take the signal cleanly * and report that. */ - sp &= ~7UL; + sp &= ~15UL; - return (void __user *)(sp - framesize); + return (void __user *) sp; } static int save_fpu_state32(struct pt_regs *regs, __siginfo_fpu_t __user *fpu) diff --git a/arch/sparc/kernel/signal_32.c b/arch/sparc/kernel/signal_32.c index 7ce1a10..9882df9 100644 --- a/arch/sparc/kernel/signal_32.c +++ b/arch/sparc/kernel/signal_32.c @@ -267,15 +267,17 @@ static inline void __user *get_sigframe(struct sigaction *sa, struct pt_regs *re sp = current->sas_ss_sp + current->sas_ss_size; } + sp -= framesize; + /* Always align the stack frame. This handles two cases. First, * sigaltstack need not be mindful of platform specific stack * alignment. Second, if we took this signal because the stack * is not aligned properly, we'd like to take the signal cleanly * and report that. */ - sp &= ~7UL; + sp &= ~15UL; - return (void __user *)(sp - framesize); + return (void __user *) sp; } static inline int diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c index 647afbd..9fa48c3 100644 --- a/arch/sparc/kernel/signal_64.c +++ b/arch/sparc/kernel/signal_64.c @@ -353,7 +353,7 @@ segv: /* Checks if the fp is valid */ static int invalid_frame_pointer(void __user *fp, int fplen) { - if (((unsigned long) fp) & 7) + if (((unsigned long) fp) & 15) return 1; return 0; } @@ -396,15 +396,17 @@ static inline void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs * sp = current->sas_ss_sp + current->sas_ss_size; } + sp -= framesize; + /* Always align the stack frame. This handles two cases. First, * sigaltstack need not be mindful of platform specific stack * alignment. Second, if we took this signal because the stack * is not aligned properly, we'd like to take the signal cleanly * and report that. */ - sp &= ~7UL; + sp &= ~15UL; - return (void __user *)(sp - framesize); + return (void __user *) sp; } static inline void -- 1.6.6.1 -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
