From: Johannes Weiner <hannes@xxxxxxxxxxx> [ Upstream commit 609838cfed972d49a65aac7923a9ff5cbe482e30 ] A few remaining architectures directly kill the page faulting task in an out of memory situation. This is usually not a good idea since that task might not even use a significant amount of memory and so may not be the optimal victim to resolve the situation. Since 2.6.29's 1c0fe6e ("mm: invoke oom-killer from page fault") there is a hook that architecture page fault handlers are supposed to call to invoke the OOM killer and let it pick the right task to kill. Convert the remaining architectures over to this hook. To have the previous behavior of simply taking out the faulting task the vm.oom_kill_allocating_task sysctl can be set to 1. Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> Reviewed-by: Michal Hocko <mhocko@xxxxxxx> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Acked-by: David Rientjes <rientjes@xxxxxxxxxx> Acked-by: Vineet Gupta <vgupta@xxxxxxxxxxxx> [arch/arc bits] Cc: James Hogan <james.hogan@xxxxxxxxxx> Cc: David Howells <dhowells@xxxxxxxxxx> Cc: Jonas Bonn <jonas@xxxxxxxxxxxx> Cc: Chen Liqin <liqin.chen@xxxxxxxxxxxxx> Cc: Lennox Wu <lennox.wu@xxxxxxxxx> Cc: Chris Metcalf <cmetcalf@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Cong Wang <xiyou.wangcong@xxxxxxxxx> --- arch/arc/mm/fault.c | 6 ++++-- arch/metag/mm/fault.c | 6 ++++-- arch/mn10300/mm/fault.c | 7 ++++--- arch/openrisc/mm/fault.c | 8 ++++---- arch/score/mm/fault.c | 8 ++++---- arch/tile/mm/fault.c | 8 ++++---- 6 files changed, 24 insertions(+), 19 deletions(-) diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c index 331a084..0902d39 100644 --- a/arch/arc/mm/fault.c +++ b/arch/arc/mm/fault.c @@ -206,8 +206,10 @@ void do_page_fault(struct pt_regs *regs, int write, unsigned long address, } up_read(&mm->mmap_sem); - if (user_mode(regs)) - do_group_exit(SIGKILL); /* This will never return */ + if (user_mode(regs)) { + pagefault_out_of_memory(); + return; + } goto no_context; diff --git a/arch/metag/mm/fault.c b/arch/metag/mm/fault.c index 2c75bf7..8fddf46 100644 --- a/arch/metag/mm/fault.c +++ b/arch/metag/mm/fault.c @@ -224,8 +224,10 @@ int do_page_fault(struct pt_regs *regs, unsigned long address, */ out_of_memory: up_read(&mm->mmap_sem); - if (user_mode(regs)) - do_group_exit(SIGKILL); + if (user_mode(regs)) { + pagefault_out_of_memory(); + return 1; + } no_context: /* Are we prepared to handle this kernel fault? */ diff --git a/arch/mn10300/mm/fault.c b/arch/mn10300/mm/fault.c index d48a84f..8a2e6de 100644 --- a/arch/mn10300/mm/fault.c +++ b/arch/mn10300/mm/fault.c @@ -345,9 +345,10 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long fault_code, */ out_of_memory: up_read(&mm->mmap_sem); - printk(KERN_ALERT "VM: killing process %s\n", tsk->comm); - if ((fault_code & MMUFCR_xFC_ACCESS) == MMUFCR_xFC_ACCESS_USR) - do_exit(SIGKILL); + if ((fault_code & MMUFCR_xFC_ACCESS) == MMUFCR_xFC_ACCESS_USR) { + pagefault_out_of_memory(); + return; + } goto no_context; do_sigbus: diff --git a/arch/openrisc/mm/fault.c b/arch/openrisc/mm/fault.c index e2bfafc..4a41f84 100644 --- a/arch/openrisc/mm/fault.c +++ b/arch/openrisc/mm/fault.c @@ -267,10 +267,10 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long address, __asm__ __volatile__("l.nop 1"); up_read(&mm->mmap_sem); - printk("VM: killing process %s\n", tsk->comm); - if (user_mode(regs)) - do_exit(SIGKILL); - goto no_context; + if (!user_mode(regs)) + goto no_context; + pagefault_out_of_memory(); + return; do_sigbus: up_read(&mm->mmap_sem); diff --git a/arch/score/mm/fault.c b/arch/score/mm/fault.c index 47b600e..6b18fb0 100644 --- a/arch/score/mm/fault.c +++ b/arch/score/mm/fault.c @@ -172,10 +172,10 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long write, down_read(&mm->mmap_sem); goto survive; } - printk("VM: killing process %s\n", tsk->comm); - if (user_mode(regs)) - do_group_exit(SIGKILL); - goto no_context; + if (!user_mode(regs)) + goto no_context; + pagefault_out_of_memory(); + return; do_sigbus: up_read(&mm->mmap_sem); diff --git a/arch/tile/mm/fault.c b/arch/tile/mm/fault.c index 3d2b81c..f7f99f9 100644 --- a/arch/tile/mm/fault.c +++ b/arch/tile/mm/fault.c @@ -573,10 +573,10 @@ static int handle_page_fault(struct pt_regs *regs, down_read(&mm->mmap_sem); goto survive; } - pr_alert("VM: killing process %s\n", tsk->comm); - if (!is_kernel_mode) - do_group_exit(SIGKILL); - goto no_context; + if (is_kernel_mode) + goto no_context; + pagefault_out_of_memory(); + return 0; do_sigbus: up_read(&mm->mmap_sem); -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html