From 3ada43e732678e1f1ed0830c7407eef99ad63c46 Mon Sep 17 00:00:00 2001 From: antirez Date: Thu, 26 Apr 2012 16:21:19 +0200 Subject: [PATCH] Don't use an alternative stack for SIGSEGV & co. This commit reverts most of c575766202773c858be0870c20cd495b722927c3, in order to use back main stack for signal handling. The main reason is that otherwise it is completely pointless that we do a lot of efforts to print the stack trace on crash, and the content of the stack and registers as well. Using an alternate stack broken this feature completely. --- src/redis.c | 14 +------------- 1 file changed, 1 insertion(+), 13 deletions(-) diff --git a/src/redis.c b/src/redis.c index cb4883cc..fd53e248 100644 --- a/src/redis.c +++ b/src/redis.c @@ -62,9 +62,6 @@ double R_Zero, R_PosInf, R_NegInf, R_Nan; /*================================= Globals ================================= */ -/* Alternate stack for SIGSEGV/etc handlers */ -char altstack[SIGSTKSZ]; - /* Global vars */ struct redisServer server; /* server global state */ struct redisCommand *commandTable; @@ -2351,13 +2348,6 @@ static void sigtermHandler(int sig) { void setupSignalHandlers(void) { struct sigaction act; - stack_t stack; - - stack.ss_sp = altstack; - stack.ss_flags = 0; - stack.ss_size = SIGSTKSZ; - - sigaltstack(&stack, NULL); /* When the SA_SIGINFO flag is set in sa_flags then sa_sigaction is used. * Otherwise, sa_handler is used. */ @@ -2367,10 +2357,8 @@ void setupSignalHandlers(void) { sigaction(SIGTERM, &act, NULL); #ifdef HAVE_BACKTRACE - /* Use alternate stack so we don't clobber stack in case of segv, or when we run out of stack .. - * also resethand & nodefer so we can get interrupted (and killed) if we cause SEGV during SEGV handler */ sigemptyset(&act.sa_mask); - act.sa_flags = SA_NODEFER | SA_ONSTACK | SA_RESETHAND | SA_SIGINFO; + act.sa_flags = SA_NODEFER | SA_RESETHAND | SA_SIGINFO; act.sa_sigaction = sigsegvHandler; sigaction(SIGSEGV, &act, NULL); sigaction(SIGBUS, &act, NULL); -- 2.45.2