Re: sparc/ppc/arm compat siginfo ABI regressions: sending SIGFPE via kill() returns wrong values in si_pid and si_uid

[Linus Torvalds]

Does this attached patch perhaps fix the ARM case?

It just uses FPE_FLTUNK as the default si_code for SIGFPE, which seems
sane enough. And then gets rid of FPE_FIXME, which should resolve the
nasty case.

Hmm? Entirely untested, and I didn't really look at the test-case in
question since I can't really run it anyway.

Well, I could run it all on x86-64, but it doesn't have that FPE_FIXME
case at all.

                 Linus
 arch/arm/include/uapi/asm/siginfo.h | 7 -------
 arch/arm/vfp/vfpmodule.c            | 4 ++--
 2 files changed, 2 insertions(+), 9 deletions(-)

diff --git a/arch/arm/include/uapi/asm/siginfo.h b/arch/arm/include/uapi/asm/siginfo.h
index d0513880be21..d87beeedb4c4 100644
--- a/arch/arm/include/uapi/asm/siginfo.h
+++ b/arch/arm/include/uapi/asm/siginfo.h
@@ -3,11 +3,4 @@
 
 #include <asm-generic/siginfo.h>
 
-/*
- * SIGFPE si_codes
- */
-#ifdef __KERNEL__
-#define FPE_FIXME	0	/* Broken dup of SI_USER */
-#endif /* __KERNEL__ */
-
 #endif
diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index 4c375e11ae95..012c6e690303 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -251,13 +251,13 @@ static void vfp_panic(char *reason, u32 inst)
  */
 static void vfp_raise_exceptions(u32 exceptions, u32 inst, u32 fpscr, struct pt_regs *regs)
 {
-	int si_code = 0;
+	int si_code = FPE_FLTUNK;
 
 	pr_debug("VFP: raising exceptions %08x\n", exceptions);
 
 	if (exceptions == VFP_EXCEPTION_ERROR) {
 		vfp_panic("unhandled bounce", inst);
-		vfp_raise_sigfpe(FPE_FIXME, regs);
+		vfp_raise_sigfpe(si_code, regs);
 		return;
 	}