diff options
| author | Paul Mackerras <paulus@samba.org> | 2005-11-14 21:55:15 +1100 |
|---|---|---|
| committer | Paul Mackerras <paulus@samba.org> | 2005-11-15 11:11:32 +1100 |
| commit | cc657f53928997c65bf2409c45166c6ceee8d306 (patch) | |
| tree | 247e16076381a947b4305bb6467acde1189f3918 | |
| parent | 493f25ef4087395891c99fcfe2c72e62e293e89f (diff) | |
powerpc: Fix clearing of the FPSCR when invoking a signal handler
As pointed out by Gary Byers, we were clearing the image of the FPSCR
(floating point status and control register) in the thread_struct before
copying it to the user stack when invoking a signal. Thus the task
would see its FPSCR getting cleared when it took a signal.
While fixing it I noticed that our swapcontext system call was also
clearing FPSCR. It shouldn't, so I fixed that too.
Signed-off-by: Paul Mackerras <paulus@samba.org>
| -rw-r--r-- | arch/powerpc/kernel/signal_32.c | 7 | ||||
| -rw-r--r-- | arch/powerpc/kernel/signal_64.c | 6 |
2 files changed, 8 insertions, 5 deletions
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c index 8bdf95b7e42..5a2eba60dd3 100644 --- a/arch/powerpc/kernel/signal_32.c +++ b/arch/powerpc/kernel/signal_32.c @@ -403,8 +403,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame, ELF_NFPREG * sizeof(double))) return 1; - current->thread.fpscr.val = 0; /* turn off all fp exceptions */ - #ifdef CONFIG_ALTIVEC /* save altivec registers */ if (current->thread.used_vr) { @@ -818,6 +816,9 @@ static int handle_rt_signal(unsigned long sig, struct k_sigaction *ka, goto badframe; regs->link = (unsigned long) frame->tramp; } + + current->thread.fpscr.val = 0; /* turn off all fp exceptions */ + if (put_user(regs->gpr[1], (u32 __user *)newsp)) goto badframe; regs->gpr[1] = newsp; @@ -1097,6 +1098,8 @@ static int handle_signal(unsigned long sig, struct k_sigaction *ka, regs->link = (unsigned long) frame->mctx.tramp; } + current->thread.fpscr.val = 0; /* turn off all fp exceptions */ + if (put_user(regs->gpr[1], (u32 __user *)newsp)) goto badframe; regs->gpr[1] = newsp; diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c index 58194e15071..1decf278553 100644 --- a/arch/powerpc/kernel/signal_64.c +++ b/arch/powerpc/kernel/signal_64.c @@ -131,9 +131,6 @@ static long setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, flush_fp_to_thread(current); - /* Make sure signal doesn't get spurrious FP exceptions */ - current->thread.fpscr.val = 0; - #ifdef CONFIG_ALTIVEC err |= __put_user(v_regs, &sc->v_regs); @@ -423,6 +420,9 @@ static int setup_rt_frame(int signr, struct k_sigaction *ka, siginfo_t *info, if (err) goto badframe; + /* Make sure signal handler doesn't get spurious FP exceptions */ + current->thread.fpscr.val = 0; + /* Set up to return from userspace. */ if (vdso64_rt_sigtramp && current->thread.vdso_base) { regs->link = current->thread.vdso_base + vdso64_rt_sigtramp; |