diff options
Diffstat (limited to 'powerpc-Fix-deadlock-in-icswx-code.patch')
| -rw-r--r-- | powerpc-Fix-deadlock-in-icswx-code.patch | 74 |
1 files changed, 0 insertions, 74 deletions
diff --git a/powerpc-Fix-deadlock-in-icswx-code.patch b/powerpc-Fix-deadlock-in-icswx-code.patch deleted file mode 100644 index a2ce3cf76..000000000 --- a/powerpc-Fix-deadlock-in-icswx-code.patch +++ /dev/null @@ -1,74 +0,0 @@ -From patchwork Wed Sep 14 19:43:15 2011 -Content-Type: text/plain; charset="utf-8" -MIME-Version: 1.0 -Content-Transfer-Encoding: 7bit -Subject: powerpc: Fix deadlock in icswx code -Date: Wed, 14 Sep 2011 09:43:15 -0000 -From: Anton Blanchard <anton@samba.org> -X-Patchwork-Id: 114701 -Message-Id: <20110915054315.5e5ae062@kryten> -To: benh@kernel.crashing.org, paulus@samba.org -Cc: linuxppc-dev@lists.ozlabs.org - -The icswx code introduced an A-B B-A deadlock: - - CPU0 CPU1 - ---- ---- -lock(&anon_vma->mutex); - lock(&mm->mmap_sem); - lock(&anon_vma->mutex); -lock(&mm->mmap_sem); - -Instead of using the mmap_sem to keep mm_users constant, take the -page table spinlock. - -Signed-off-by: Anton Blanchard <anton@samba.org> -Cc: <stable@kernel.org> - ---- - - -diff --git a/arch/powerpc/mm/mmu_context_hash64.c b/arch/powerpc/mm/mmu_context_hash64.c -index 3bafc3d..4ff587e 100644 ---- a/arch/powerpc/mm/mmu_context_hash64.c -+++ b/arch/powerpc/mm/mmu_context_hash64.c -@@ -136,8 +136,8 @@ int use_cop(unsigned long acop, struct mm_struct *mm) - if (!mm || !acop) - return -EINVAL; - -- /* We need to make sure mm_users doesn't change */ -- down_read(&mm->mmap_sem); -+ /* The page_table_lock ensures mm_users won't change under us */ -+ spin_lock(&mm->page_table_lock); - spin_lock(mm->context.cop_lockp); - - if (mm->context.cop_pid == COP_PID_NONE) { -@@ -164,7 +164,7 @@ int use_cop(unsigned long acop, struct mm_struct *mm) - - out: - spin_unlock(mm->context.cop_lockp); -- up_read(&mm->mmap_sem); -+ spin_unlock(&mm->page_table_lock); - - return ret; - } -@@ -185,8 +185,8 @@ void drop_cop(unsigned long acop, struct mm_struct *mm) - if (WARN_ON_ONCE(!mm)) - return; - -- /* We need to make sure mm_users doesn't change */ -- down_read(&mm->mmap_sem); -+ /* The page_table_lock ensures mm_users won't change under us */ -+ spin_lock(&mm->page_table_lock); - spin_lock(mm->context.cop_lockp); - - mm->context.acop &= ~acop; -@@ -213,7 +213,7 @@ void drop_cop(unsigned long acop, struct mm_struct *mm) - } - - spin_unlock(mm->context.cop_lockp); -- up_read(&mm->mmap_sem); -+ spin_unlock(&mm->page_table_lock); - } - EXPORT_SYMBOL_GPL(drop_cop); - |