From eaf05be039cf5adfba5b1846452ce89646110fdb Mon Sep 17 00:00:00 2001 From: Ivan Kokshaysky Date: Thu, 30 Jun 2005 20:02:18 +0400 Subject: [PATCH] [PATCH] alpha smp fix As usual, the reason of this breakage is quite silly: in do_entIF, we are checking for PS == 0 to see whether it was a kernel BUG() or userspace trap. It works, unless BUG() happens in interrupt - PS is not 0 in kernel mode due to non-zero IPL, and the things get messed up horribly then. In this particular case it was BUG_ON(!irqs_disabled()) triggered in run_posix_cpu_timers(), so we ended up shooting "current" with the bursts of one SIGTRAP and three SIGILLs on every timer tick. ;-) --- arch/alpha/kernel/traps.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/alpha/kernel/traps.c b/arch/alpha/kernel/traps.c index fd7bd17cc960..6f509a644bdd 100644 --- a/arch/alpha/kernel/traps.c +++ b/arch/alpha/kernel/traps.c @@ -240,7 +240,7 @@ do_entIF(unsigned long type, struct pt_regs *regs) siginfo_t info; int signo, code; - if (regs->ps == 0) { + if ((regs->ps & ~IPL_MAX) == 0) { if (type == 1) { const unsigned int *data = (const unsigned int *) regs->pc; -- 2.20.1