From 1087e9b4ff708976499b4de541d9e1d57d49b60a Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Sun, 4 Oct 2009 02:20:11 +0200 Subject: 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 --- kernel/sys.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) (limited to 'kernel/sys.c') diff --git a/kernel/sys.c b/kernel/sys.c index 255475d..f6afe07 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; -- cgit v1.1 From 0d0df599f1f11f12d589318bacb59a50fb5c0310 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Mon, 26 Oct 2009 16:49:34 -0700 Subject: connector: fix regression introduced by sid connector Since commit 02b51df1b07b4e9ca823c89284e704cadb323cd1 (proc connector: add event for process becoming session leader) we have the following warning: Badness at kernel/softirq.c:143 [...] Krnl PSW : 0404c00180000000 00000000001481d4 (local_bh_enable+0xb0/0xe0) [...] Call Trace: ([<000000013fe04100>] 0x13fe04100) [<000000000048a946>] sk_filter+0x9a/0xd0 [<000000000049d938>] netlink_broadcast+0x2c0/0x53c [<00000000003ba9ae>] cn_netlink_send+0x272/0x2b0 [<00000000003baef0>] proc_sid_connector+0xc4/0xd4 [<0000000000142604>] __set_special_pids+0x58/0x90 [<0000000000159938>] sys_setsid+0xb4/0xd8 [<00000000001187fe>] sysc_noemu+0x10/0x16 [<00000041616cb266>] 0x41616cb266 The warning is ---> WARN_ON_ONCE(in_irq() || irqs_disabled()); The network code must not be called with disabled interrupts but sys_setsid holds the tasklist_lock with spinlock_irq while calling the connector. After a discussion we agreed that we can move proc_sid_connector from __set_special_pids to sys_setsid. We also agreed that it is sufficient to change the check from task_session(curr) != pid into err > 0, since if we don't change the session, this means we were already the leader and return -EPERM. One last thing: There is also daemonize(), and some people might want to get a notification in that case. Since daemonize() is only needed if a user space does kernel_thread this does not look important (and there seems to be no consensus if this connector should be called in daemonize). If we really want this, we can add proc_sid_connector to daemonize() in an additional patch (Scott?) Signed-off-by: Christian Borntraeger Cc: Scott James Remnant Cc: Matt Helsley Cc: David S. Miller Acked-by: Oleg Nesterov Acked-by: Evgeniy Polyakov Acked-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/sys.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'kernel/sys.c') diff --git a/kernel/sys.c b/kernel/sys.c index 255475d..1828f8d 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1110,6 +1110,8 @@ SYSCALL_DEFINE0(setsid) err = session; out: write_unlock_irq(&tasklist_lock); + if (err > 0) + proc_sid_connector(group_leader); return err; } -- cgit v1.1