From 1087e9b4ff708976499b4de541d9e1d57d49b60a Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Sun, 4 Oct 2009 02:20:11 +0200 Subject: [PATCH] HWPOISON: Clean up PR_MCE_KILL interface While writing the manpage I noticed some shortcomings in the current interface. - Define symbolic names for all the different values - Boundary check the kill mode values - For symmetry add a get interface too. This allows library code to get/set the current state. - For consistency define a PR_MCE_KILL_DEFAULT value Signed-off-by: Andi Kleen --- include/linux/prctl.h | 12 ++++++++++++ kernel/sys.c | 23 ++++++++++++++++++----- 2 files changed, 30 insertions(+), 5 deletions(-) diff --git a/include/linux/prctl.h b/include/linux/prctl.h index 931150566ade..a3baeb2c2161 100644 --- a/include/linux/prctl.h +++ b/include/linux/prctl.h @@ -88,6 +88,18 @@ #define PR_TASK_PERF_EVENTS_DISABLE 31 #define PR_TASK_PERF_EVENTS_ENABLE 32 +/* + * Set early/late kill mode for hwpoison memory corruption. + * This influences when the process gets killed on a memory corruption. + */ #define PR_MCE_KILL 33 +# define PR_MCE_KILL_CLEAR 0 +# define PR_MCE_KILL_SET 1 + +# define PR_MCE_KILL_LATE 0 +# define PR_MCE_KILL_EARLY 1 +# define PR_MCE_KILL_DEFAULT 2 + +#define PR_MCE_KILL_GET 34 #endif /* _LINUX_PRCTL_H */ diff --git a/kernel/sys.c b/kernel/sys.c index 255475d163e0..f6afe07d6c0b 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1546,24 +1546,37 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, if (arg4 | arg5) return -EINVAL; switch (arg2) { - case 0: + case PR_MCE_KILL_CLEAR: if (arg3 != 0) return -EINVAL; current->flags &= ~PF_MCE_PROCESS; break; - case 1: + case PR_MCE_KILL_SET: current->flags |= PF_MCE_PROCESS; - if (arg3 != 0) + if (arg3 == PR_MCE_KILL_EARLY) current->flags |= PF_MCE_EARLY; - else + else if (arg3 == PR_MCE_KILL_LATE) current->flags &= ~PF_MCE_EARLY; + else if (arg3 == PR_MCE_KILL_DEFAULT) + current->flags &= + ~(PF_MCE_EARLY|PF_MCE_PROCESS); + else + return -EINVAL; break; default: return -EINVAL; } error = 0; break; - + case PR_MCE_KILL_GET: + if (arg2 | arg3 | arg4 | arg5) + return -EINVAL; + if (current->flags & PF_MCE_PROCESS) + error = (current->flags & PF_MCE_EARLY) ? + PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE; + else + error = PR_MCE_KILL_DEFAULT; + break; default: error = -EINVAL; break; -- 2.20.1