Commit 250df6ed274d767da844a5d9f05720b804240197 "fs: protect inode->i_state with inode->i_lock" introduces a change to igrab to acquire inode->i_lock. This change causes a panic on boot on my ARM EP93xx board when the rootfs uses NFS. The problem occurs because nfs_inode_add_request acquires inode->i_lock and then calls igrab, resulting in the following panic: BUG: spinlock recursion on CPU#0, getty/262 lock: cc421cb4, .magic: dead4ead, .owner: getty/262, .owner_cpu: 0 [<c0031b0c>] (unwind_backtrace+0x0/0xe4) from [<c015f16c>] (do_raw_spin_lock+0x40/0x13c) [<c015f16c>] (do_raw_spin_lock+0x40/0x13c) from [<c00a938c>] (igrab+0x14/0x48) [<c00a938c>] (igrab+0x14/0x48) from [<c01186bc>] (nfs_updatepage+0x2e0/0x524) [<c01186bc>] (nfs_updatepage+0x2e0/0x524) from [<c010b19c>] (nfs_write_end+0x23c/0x270) [<c010b19c>] (nfs_write_end+0x23c/0x270) from [<c006b484>] (generic_file_buffered_write+0x180/0x248) [<c006b484>] (generic_file_buffered_write+0x180/0x248) from [<c006d060>] (__generic_file_aio_write+0x3b8/0x3f4) [<c006d060>] (__generic_file_aio_write+0x3b8/0x3f4) from [<c006d108>] (generic_file_aio_write+0x6c/0xdc) [<c006d108>] (generic_file_aio_write+0x6c/0xdc) from [<c010bce0>] (nfs_file_write+0xec/0x178) [<c010bce0>] (nfs_file_write+0xec/0x178) from [<c00956ac>] (do_sync_write+0xa4/0xe4) [<c00956ac>] (do_sync_write+0xa4/0xe4) from [<c00960c8>] (vfs_write+0xb4/0x12c) [<c00960c8>] (vfs_write+0xb4/0x12c) from [<c00961f0>] (sys_write+0x3c/0x68) [<c00961f0>] (sys_write+0x3c/0x68) from [<c002c8e0>] (ret_fast_syscall+0x0/0x2c) This series introduces a new function called __igrab, which is an unlocked version of igrab and modifies nfs_inode_add_request to use the unlocked version. Ryan Mallon (2): Add unlocked version of igrab. Use __igrab instead of igrab in nfs_inode_add_request fs/inode.c | 16 ++++++++++++---- fs/nfs/write.c | 2 +- include/linux/fs.h | 1 + 3 files changed, 14 insertions(+), 5 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
