diff options
| author | Chuck Ebbert <76306.1226@compuserve.com> | 2005-09-12 18:49:25 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-09-12 10:50:58 -0700 |
| commit | ff347b221512a83e7b08356729e3e2c14346e29e (patch) | |
| tree | 3af9934eecd9ce119a840f53912e657951da9656 | |
| parent | 847815760cc0f41985b3185d780aa4369fcb475d (diff) | |
[PATCH] x86-64: Fix incorrect FP signals
This is the same patch that went into i386 just before 2.6.13
came out. I still can't build 64-bit user apps, so I tested
with program (see below) in 32-bit mode on 64-bit kernel:
Before:
$ fpsig
handler: nr = 8, si = 0x0804bc90, vuc = 0x0804bd10
handler: altstack is at 0x0804b000, ebp = 0x0804bc7c
handler: si_signo = 8, si_errno = 0, si_code = 0 [unknown]
handler: fpu cwd = 0xb40, fpu swd = 0xbaa0
handler: i387 unmasked precision exception, rounded up
After:
$ fpsig
handler: nr = 8, si = 0x0804bc90, vuc = 0x0804bd10
handler: altstack is at 0x0804b000, ebp = 0x0804bc7c
handler: si_signo = 8, si_errno = 0, si_code = 6 [inexact result]
handler: fpu cwd = 0xb40, fpu swd = 0xbaa0
handler: i387 unmasked precision exception, rounded up
Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | arch/x86_64/kernel/traps.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c index 64a59cb4941..77658f7f4e8 100644 --- a/arch/x86_64/kernel/traps.c +++ b/arch/x86_64/kernel/traps.c @@ -795,13 +795,16 @@ asmlinkage void do_coprocessor_error(struct pt_regs *regs) */ cwd = get_fpu_cwd(task); swd = get_fpu_swd(task); - switch (((~cwd) & swd & 0x3f) | (swd & 0x240)) { + switch (swd & ~cwd & 0x3f) { case 0x000: default: break; case 0x001: /* Invalid Op */ - case 0x041: /* Stack Fault */ - case 0x241: /* Stack Fault | Direction */ + /* + * swd & 0x240 == 0x040: Stack Underflow + * swd & 0x240 == 0x240: Stack Overflow + * User must clear the SF bit (0x40) if set + */ info.si_code = FPE_FLTINV; break; case 0x002: /* Denormalize */ |