Messages in this thread Patch in this message | | | Date | Sat, 9 Jul 2005 01:02:44 +0100 (BST) | From | Hugh Dickins <> | Subject | [PATCH 03/13] move destroy_swap_extents calls |
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sys_swapon's call to destroy_swap_extents on failure is made after the final swap_list_unlock, which is faintly unsafe: another sys_swapon might already be setting up that swap_info_struct. Calling it earlier, before taking swap_list_lock, is safe. sys_swapoff's call to destroy_swap_extents was safe, but likewise move it earlier, before taking the locks (once try_to_unuse has completed, nothing can be needing the swap extents).
Signed-off-by: Hugh Dickins <hugh@veritas.com> ---
mm/swapfile.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-)
--- swap2/mm/swapfile.c 2005-07-08 19:13:33.000000000 +0100 +++ swap3/mm/swapfile.c 2005-07-08 19:13:46.000000000 +0100 @@ -1127,6 +1127,7 @@ asmlinkage long sys_swapoff(const char _ swap_list_unlock(); goto out_dput; } + destroy_swap_extents(p); down(&swapon_sem); swap_list_lock(); drain_mmlist(); @@ -1137,7 +1138,6 @@ asmlinkage long sys_swapoff(const char _ swap_map = p->swap_map; p->swap_map = NULL; p->flags = 0; - destroy_swap_extents(p); swap_device_unlock(p); swap_list_unlock(); up(&swapon_sem); @@ -1529,6 +1529,7 @@ bad_swap: set_blocksize(bdev, p->old_block_size); bd_release(bdev); } + destroy_swap_extents(p); bad_swap_2: swap_list_lock(); swap_map = p->swap_map; @@ -1538,7 +1539,6 @@ bad_swap_2: if (!(swap_flags & SWAP_FLAG_PREFER)) ++least_priority; swap_list_unlock(); - destroy_swap_extents(p); vfree(swap_map); if (swap_file) filp_close(swap_file, NULL); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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