On 03/28/2011 05:43 PM, Dave Chinner wrote: > On Mon, Mar 28, 2011 at 02:55:59PM +1300, Ryan Mallon wrote: >> 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. > > It's called ihold() and already exists. Thanks. Missed that one. Is ihold the correct replacement for the fs/ceph cases I mentioned in my other email? ~Ryan -- Bluewater Systems Ltd - ARM Technology Solution Centre Ryan Mallon 5 Amuri Park, 404 Barbadoes St ryan@xxxxxxxxxxxxxxxx PO Box 13 889, Christchurch 8013 http://www.bluewatersys.com New Zealand Phone: +64 3 3779127 Freecall: Australia 1800 148 751 Fax: +64 3 3779135 USA 1800 261 2934 -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
