Re: [PATCH 1/3] signal: Add FPE_FLTUNK si_code for undiagnosable fp exceptions
From: James Morse <james.morse@arm.com>
Date: 2018-02-22 12:14:17
Also in:
linux-api, linux-arm-kernel
Hi Dave, On 21/02/18 16:02, Dave Martin wrote:
Some architectures cannot always report accurately what kind of floating-point exception triggered a floating-point exception trap. This can occur with fp exceptions occuring on lanes in a vector
(Nit: occurring)
instruction on arm64 for example. Rather than have every architecture come up with its own way of descrbing such a condition, this patch adds a common FPE_FLTUNK do
(Nits: describing; 'to report')
report that an fp exception caused a trap but we cannot be certain which kind of fp exception it was.
quoted hunk ↗ jump to hunk
diff --git a/include/uapi/asm-generic/siginfo.h b/include/uapi/asm-generic/siginfo.h index 85dc965..10304de 100644 --- a/include/uapi/asm-generic/siginfo.h +++ b/include/uapi/asm-generic/siginfo.h@@ -229,7 +229,8 @@ typedef struct siginfo { # define __FPE_INVASC 12 /* invalid ASCII digit */ # define __FPE_INVDEC 13 /* invalid decimal digit */ #endif -#define NSIGFPE 13 +#define FPE_FLTUNK 14 /* undiagnosed floating-point exception */ +#define NSIGFPE 14
It looks like x86's compat relies on this value not changing: | arch/x86/kernel/signal_compat.c: BUILD_BUG_ON(NSIGFPE != 13); | include/uapi/asm-generic/siginfo.h:#define NSIGFPE 13 (from v4.16-rc2) Thanks, James