From cc9f72e474a4da365896d0e528da324f205e8b31 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Sun, 16 Jul 2017 20:04:58 -0500 Subject: 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" Cc: sparclinux@vger.kernel.org Signed-off-by: "Eric W. Biederman" --- arch/sparc/kernel/traps_64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/sparc/kernel/traps_64.c') diff --git a/arch/sparc/kernel/traps_64.c b/arch/sparc/kernel/traps_64.c index 196ee5eb4d48..e882e128faa3 100644 --- a/arch/sparc/kernel/traps_64.c +++ b/arch/sparc/kernel/traps_64.c @@ -2258,7 +2258,7 @@ static void do_fpe_common(struct pt_regs *regs) info.si_errno = 0; info.si_addr = (void __user *)regs->tpc; info.si_trapno = 0; - info.si_code = __SI_FAULT; + info.si_code = FPE_FIXME; if ((fsr & 0x1c000) == (1 << 14)) { if (fsr & 0x10) info.si_code = FPE_FLTINV; -- cgit