From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wu Fengguang Subject: [PATCH 05/22] HWPOISON: Add basic support for poisoned pages in fault handler v3 Date: Mon, 15 Jun 2009 10:45:25 +0800 Message-ID: <20090615031253.003740564@intel.com> References: <20090615024520.786814520@intel.com> Return-path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with SMTP id 683B16B007E for ; Sun, 14 Jun 2009 23:14:35 -0400 (EDT) Content-Disposition: inline; filename=vm-fault-poison Sender: owner-linux-mm@kvack.org To: Andrew Morton Cc: LKML , Andi Kleen , Ingo Molnar , Mel Gorman , "Wu, Fengguang" , Thomas Gleixner , "H. Peter Anvin" , Peter Zijlstra , Nick Piggin , Hugh Dickins , Andi Kleen , "riel@redhat.com" , "chris.mason@oracle.com" , "linux-mm@kvack.org" List-Id: linux-mm.kvack.org From: Andi Kleen - Add a new VM_FAULT_HWPOISON error code to handle_mm_fault. Right now architectures have to explicitely enable poison page support, so this is forward compatible to all architectures. They only need to add it when they enable poison page support. - Add poison page handling in swap in fault code v2: Add missing delayacct_clear_flag (Hidehiro Kawai) v3: Really use delayacct_clear_flag (Hidehiro Kawai) Reviewed-by: Wu Fengguang Reviewed-by: Hidehiro Kawai Signed-off-by: Andi Kleen --- include/linux/mm.h | 3 ++- mm/memory.c | 18 +++++++++++++++--- 2 files changed, 17 insertions(+), 4 deletions(-) --- sound-2.6.orig/mm/memory.c +++ sound-2.6/mm/memory.c @@ -1315,7 +1315,8 @@ int __get_user_pages(struct task_struct if (ret & VM_FAULT_ERROR) { if (ret & VM_FAULT_OOM) return i ? i : -ENOMEM; - else if (ret & VM_FAULT_SIGBUS) + if (ret & + (VM_FAULT_HWPOISON|VM_FAULT_SIGBUS)) return i ? i : -EFAULT; BUG(); } @@ -2595,8 +2596,15 @@ static int do_swap_page(struct mm_struct goto out; entry = pte_to_swp_entry(orig_pte); - if (is_migration_entry(entry)) { - migration_entry_wait(mm, pmd, address); + if (unlikely(non_swap_entry(entry))) { + if (is_migration_entry(entry)) { + migration_entry_wait(mm, pmd, address); + } else if (is_hwpoison_entry(entry)) { + ret = VM_FAULT_HWPOISON; + } else { + print_bad_pte(vma, address, pte, NULL); + ret = VM_FAULT_OOM; + } goto out; } delayacct_set_flag(DELAYACCT_PF_SWAPIN); @@ -2620,6 +2628,10 @@ static int do_swap_page(struct mm_struct /* Had to read the page from swap area: Major fault */ ret = VM_FAULT_MAJOR; count_vm_event(PGMAJFAULT); + } else if (PageHWPoison(page)) { + ret = VM_FAULT_HWPOISON; + delayacct_clear_flag(DELAYACCT_PF_SWAPIN); + goto out; } lock_page(page); --- sound-2.6.orig/include/linux/mm.h +++ sound-2.6/include/linux/mm.h @@ -700,11 +700,12 @@ static inline int page_mapped(struct pag #define VM_FAULT_SIGBUS 0x0002 #define VM_FAULT_MAJOR 0x0004 #define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */ +#define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned page */ #define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not return page */ #define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */ -#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS) +#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_HWPOISON) /* * Can be called by the pagefault handler when it gets a VM_FAULT_OOM. -- -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org