path: root/arch/sparc/include/uapi/asm
diff options
authorEric W. Biederman <ebiederm@xmission.com>2017-07-16 20:04:58 -0500
committerEric W. Biederman <ebiederm@xmission.com>2017-07-19 19:13:14 -0500
commitcc9f72e474a4da365896d0e528da324f205e8b31 (patch)
treecda3b38a86ae57b171c6094a6ef405b17ac75260 /arch/sparc/include/uapi/asm
parent80dce5e37493029e1fb7f890b960264ba9a46fe4 (diff)
signal/sparc: Document a conflict with SI_USER with SIGFPE
Setting si_code to __SI_FAULT results in a userspace seeing an si_code of 0. This is the same si_code as SI_USER. Posix and common sense requires that SI_USER not be a signal specific si_code. As such this use of 0 for the si_code is a pretty horribly broken ABI. This was introduced in 2.3.41 so this mess has had a long time for people to be able to start depending on it. As this bug has existed for 17 years already I don't know if it is worth fixing. It is definitely worth documenting what is going on so that no one decides to copy this bad decision. Cc: "David S. Miller" <davem@davemloft.net> Cc: sparclinux@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Diffstat (limited to 'arch/sparc/include/uapi/asm')
1 files changed, 7 insertions, 0 deletions
diff --git a/arch/sparc/include/uapi/asm/siginfo.h b/arch/sparc/include/uapi/asm/siginfo.h
index 2d9b79ccaa50..da2126e0c536 100644
--- a/arch/sparc/include/uapi/asm/siginfo.h
+++ b/arch/sparc/include/uapi/asm/siginfo.h
@@ -17,6 +17,13 @@
#define SI_NOINFO 32767 /* no information in siginfo_t */
+ * SIGFPE si_codes
+ */
+#ifdef __KERNEL__
+#define FPE_FIXME (__SI_FAULT|0) /* Broken dup of SI_USER */
+#endif /* __KERNEL__ */
* SIGEMT si_codes
#define EMT_TAGOVF (__SI_FAULT|1) /* tag overflow */

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