| Message ID | 20170503114454.GE10084@quack2.suse.cz (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, May 03, 2017 at 01:44:54PM +0200, Jan Kara wrote: > On Tue 02-05-17 19:22:22, Corentin Labbe wrote: > > On Tue, May 02, 2017 at 06:27:04PM +0200, Jan Kara wrote: > > > Hello, > > > > > > On Fri 28-04-17 11:56:24, Corentin Labbe wrote: > > > > Since linux next-20170421, mounting nfs give me: > > > > [ 774.994934] ------------[ cut here ]------------ > > > > [ 774.994975] WARNING: CPU: 1 PID: 10284 at /linux-next/fs/sysfs/dir.c:31 sysfs_warn_dup+0x64/0x74 > > > > [ 774.994985] sysfs: cannot create duplicate filename '/devices/virtual/bdi/0:32' > > > > [ 774.994992] Modules linked in: axp20x_usb_power gpio_axp209 nvmem_sunxi_sid sun4i_dma sun4i_ss virt_dma > > > > [ 774.995047] CPU: 1 PID: 10284 Comm: mount.nfs Not tainted 4.11.0-rc4+ #14 > > > > [ 774.995054] Hardware name: Allwinner sun7i (A20) Family > > > > [ 774.995085] [<c010f19c>] (unwind_backtrace) from [<c010bc74>] (show_stack+0x10/0x14) > > > > [ 774.995104] [<c010bc74>] (show_stack) from [<c03c6e24>] (dump_stack+0x78/0x8c) > > > > [ 774.995121] [<c03c6e24>] (dump_stack) from [<c0122200>] (__warn+0xe8/0x100) > > > > [ 774.995135] [<c0122200>] (__warn) from [<c0122250>] (warn_slowpath_fmt+0x38/0x48) > > > > [ 774.995150] [<c0122250>] (warn_slowpath_fmt) from [<c02ac178>] (sysfs_warn_dup+0x64/0x74) > > > > [ 774.995167] [<c02ac178>] (sysfs_warn_dup) from [<c02ac254>] (sysfs_create_dir_ns+0x84/0x94) > > > > [ 774.995184] [<c02ac254>] (sysfs_create_dir_ns) from [<c03c8b8c>] (kobject_add_internal+0x9c/0x2ec) > > > > [ 774.995199] [<c03c8b8c>] (kobject_add_internal) from [<c03c8e24>] (kobject_add+0x48/0x98) > > > > [ 774.995217] [<c03c8e24>] (kobject_add) from [<c048d75c>] (device_add+0xe4/0x5a0) > > > > [ 774.995232] [<c048d75c>] (device_add) from [<c048ddb4>] (device_create_groups_vargs+0xac/0xbc) > > > > [ 774.995247] [<c048ddb4>] (device_create_groups_vargs) from [<c048dde4>] (device_create_vargs+0x20/0x28) > > > > [ 774.995263] [<c048dde4>] (device_create_vargs) from [<c02075c8>] (bdi_register_va+0x44/0xfc) > > > > [ 774.995280] [<c02075c8>] (bdi_register_va) from [<c023d378>] (super_setup_bdi_name+0x48/0xa4) > > > > [ 774.995299] [<c023d378>] (super_setup_bdi_name) from [<c0312ef4>] (nfs_fill_super+0x1a4/0x204) > > > > [ 774.995315] [<c0312ef4>] (nfs_fill_super) from [<c03133f0>] (nfs_fs_mount_common+0x140/0x1e8) > > > > [ 774.995333] [<c03133f0>] (nfs_fs_mount_common) from [<c03335cc>] (nfs4_remote_mount+0x50/0x58) > > > > [ 774.995349] [<c03335cc>] (nfs4_remote_mount) from [<c023ef98>] (mount_fs+0x14/0xa4) > > > > [ 774.995368] [<c023ef98>] (mount_fs) from [<c025cba0>] (vfs_kern_mount+0x54/0x128) > > > > [ 774.995385] [<c025cba0>] (vfs_kern_mount) from [<c033352c>] (nfs_do_root_mount+0x80/0xa0) > > > > [ 774.995400] [<c033352c>] (nfs_do_root_mount) from [<c0333818>] (nfs4_try_mount+0x28/0x3c) > > > > [ 774.995415] [<c0333818>] (nfs4_try_mount) from [<c0313874>] (nfs_fs_mount+0x2cc/0x8c4) > > > > [ 774.995430] [<c0313874>] (nfs_fs_mount) from [<c023ef98>] (mount_fs+0x14/0xa4) > > > > [ 774.995445] [<c023ef98>] (mount_fs) from [<c025cba0>] (vfs_kern_mount+0x54/0x128) > > > > [ 774.995461] [<c025cba0>] (vfs_kern_mount) from [<c02600f0>] (do_mount+0x158/0xc7c) > > > > [ 774.995475] [<c02600f0>] (do_mount) from [<c0260f98>] (SyS_mount+0x8c/0xb4) > > > > [ 774.995491] [<c0260f98>] (SyS_mount) from [<c0107840>] (ret_fast_syscall+0x0/0x3c) > > > > [ 774.995501] ---[ end trace 0665e451f8864ff0 ]--- > > > ... > > > > The mount command is > > > > mount -t nfs -o tcp,hard,intr,async,rsize=4096,wsize=4096 192.168.1.100:/mnt/local_kernel /usr/src/ > > > > > > > > the mount command failling with: "mount.nfs: Cannot allocate memory" > > > > > > I've tried reproducing this (both with NFSv3 and NFSv4) and failed. Also I > > > have looked through the code and I fail to see how this could happen. Is > > > this the only NFS mount that you have on your system? Didn't also the > > > WARN_ON in super_setup_bdi_name() trigger? > > > > > > Can you run with the attached debug patch and post full dmesg after the > > > failure? > > > > > > > Hello > > > > I forgot to said that I have 6 nfs mount point. > > mount -t nfs -o ro,tcp,hard,intr,async,vers=3 192.168.1.100:/usr/portage /usr/portage/ > > mount -t nfs -o tcp,hard,intr,async,vers=3 192.168.1.100:/usr/local/portage /usr/local/portage/ > > mount -t nfs -o tcp,hard,intr,async,vers=3 192.168.1.100:/mnt/tempo/portages/distfiles /usr/portage/distfiles > > mount -t nfs -o tcp,hard,intr,async,vers=4 192.168.1.100:/mnt/tempo/portages/cubiedev/packages /usr/portage/packages > > mount -t nfs -o tcp,hard,intr,async,vers=4,rsize=4096,wsize=4096 192.168.1.100:/var/tmp/portage/cubie /var/tmp/portage/ > > mount -t nfs -o tcp,hard,intr,async,rsize=4096,wsize=4096 192.168.1.100:/mnt/tempo/cubie/local_kernel /usr/src/ > > > > It's always the last which fail, but strangely inverting the two last > > made everything ok. > > Thanks for more info and the debug data. I still was not able to reproduce > the issue but after pondering my head on this for some time I have found a > bug in NFS conversion which can possibly cause the behavior you observe. > Does the attached patch fix the problem for you? > > If it does not, can you also post /proc/mounts and /etc/exports from you > NFS server? > This patch fix the issue Thanks Corentin Labbe -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed 03-05-17 19:19:11, Corentin Labbe wrote: > On Wed, May 03, 2017 at 01:44:54PM +0200, Jan Kara wrote: > > On Tue 02-05-17 19:22:22, Corentin Labbe wrote: > > > On Tue, May 02, 2017 at 06:27:04PM +0200, Jan Kara wrote: > > > > Hello, > > > > > > > > On Fri 28-04-17 11:56:24, Corentin Labbe wrote: > > > > > Since linux next-20170421, mounting nfs give me: > > > > > [ 774.994934] ------------[ cut here ]------------ > > > > > [ 774.994975] WARNING: CPU: 1 PID: 10284 at /linux-next/fs/sysfs/dir.c:31 sysfs_warn_dup+0x64/0x74 > > > > > [ 774.994985] sysfs: cannot create duplicate filename '/devices/virtual/bdi/0:32' > > > > > [ 774.994992] Modules linked in: axp20x_usb_power gpio_axp209 nvmem_sunxi_sid sun4i_dma sun4i_ss virt_dma > > > > > [ 774.995047] CPU: 1 PID: 10284 Comm: mount.nfs Not tainted 4.11.0-rc4+ #14 > > > > > [ 774.995054] Hardware name: Allwinner sun7i (A20) Family > > > > > [ 774.995085] [<c010f19c>] (unwind_backtrace) from [<c010bc74>] (show_stack+0x10/0x14) > > > > > [ 774.995104] [<c010bc74>] (show_stack) from [<c03c6e24>] (dump_stack+0x78/0x8c) > > > > > [ 774.995121] [<c03c6e24>] (dump_stack) from [<c0122200>] (__warn+0xe8/0x100) > > > > > [ 774.995135] [<c0122200>] (__warn) from [<c0122250>] (warn_slowpath_fmt+0x38/0x48) > > > > > [ 774.995150] [<c0122250>] (warn_slowpath_fmt) from [<c02ac178>] (sysfs_warn_dup+0x64/0x74) > > > > > [ 774.995167] [<c02ac178>] (sysfs_warn_dup) from [<c02ac254>] (sysfs_create_dir_ns+0x84/0x94) > > > > > [ 774.995184] [<c02ac254>] (sysfs_create_dir_ns) from [<c03c8b8c>] (kobject_add_internal+0x9c/0x2ec) > > > > > [ 774.995199] [<c03c8b8c>] (kobject_add_internal) from [<c03c8e24>] (kobject_add+0x48/0x98) > > > > > [ 774.995217] [<c03c8e24>] (kobject_add) from [<c048d75c>] (device_add+0xe4/0x5a0) > > > > > [ 774.995232] [<c048d75c>] (device_add) from [<c048ddb4>] (device_create_groups_vargs+0xac/0xbc) > > > > > [ 774.995247] [<c048ddb4>] (device_create_groups_vargs) from [<c048dde4>] (device_create_vargs+0x20/0x28) > > > > > [ 774.995263] [<c048dde4>] (device_create_vargs) from [<c02075c8>] (bdi_register_va+0x44/0xfc) > > > > > [ 774.995280] [<c02075c8>] (bdi_register_va) from [<c023d378>] (super_setup_bdi_name+0x48/0xa4) > > > > > [ 774.995299] [<c023d378>] (super_setup_bdi_name) from [<c0312ef4>] (nfs_fill_super+0x1a4/0x204) > > > > > [ 774.995315] [<c0312ef4>] (nfs_fill_super) from [<c03133f0>] (nfs_fs_mount_common+0x140/0x1e8) > > > > > [ 774.995333] [<c03133f0>] (nfs_fs_mount_common) from [<c03335cc>] (nfs4_remote_mount+0x50/0x58) > > > > > [ 774.995349] [<c03335cc>] (nfs4_remote_mount) from [<c023ef98>] (mount_fs+0x14/0xa4) > > > > > [ 774.995368] [<c023ef98>] (mount_fs) from [<c025cba0>] (vfs_kern_mount+0x54/0x128) > > > > > [ 774.995385] [<c025cba0>] (vfs_kern_mount) from [<c033352c>] (nfs_do_root_mount+0x80/0xa0) > > > > > [ 774.995400] [<c033352c>] (nfs_do_root_mount) from [<c0333818>] (nfs4_try_mount+0x28/0x3c) > > > > > [ 774.995415] [<c0333818>] (nfs4_try_mount) from [<c0313874>] (nfs_fs_mount+0x2cc/0x8c4) > > > > > [ 774.995430] [<c0313874>] (nfs_fs_mount) from [<c023ef98>] (mount_fs+0x14/0xa4) > > > > > [ 774.995445] [<c023ef98>] (mount_fs) from [<c025cba0>] (vfs_kern_mount+0x54/0x128) > > > > > [ 774.995461] [<c025cba0>] (vfs_kern_mount) from [<c02600f0>] (do_mount+0x158/0xc7c) > > > > > [ 774.995475] [<c02600f0>] (do_mount) from [<c0260f98>] (SyS_mount+0x8c/0xb4) > > > > > [ 774.995491] [<c0260f98>] (SyS_mount) from [<c0107840>] (ret_fast_syscall+0x0/0x3c) > > > > > [ 774.995501] ---[ end trace 0665e451f8864ff0 ]--- > > > > ... > > > > > The mount command is > > > > > mount -t nfs -o tcp,hard,intr,async,rsize=4096,wsize=4096 192.168.1.100:/mnt/local_kernel /usr/src/ > > > > > > > > > > the mount command failling with: "mount.nfs: Cannot allocate memory" > > > > > > > > I've tried reproducing this (both with NFSv3 and NFSv4) and failed. Also I > > > > have looked through the code and I fail to see how this could happen. Is > > > > this the only NFS mount that you have on your system? Didn't also the > > > > WARN_ON in super_setup_bdi_name() trigger? > > > > > > > > Can you run with the attached debug patch and post full dmesg after the > > > > failure? > > > > > > > > > > Hello > > > > > > I forgot to said that I have 6 nfs mount point. > > > mount -t nfs -o ro,tcp,hard,intr,async,vers=3 192.168.1.100:/usr/portage /usr/portage/ > > > mount -t nfs -o tcp,hard,intr,async,vers=3 192.168.1.100:/usr/local/portage /usr/local/portage/ > > > mount -t nfs -o tcp,hard,intr,async,vers=3 192.168.1.100:/mnt/tempo/portages/distfiles /usr/portage/distfiles > > > mount -t nfs -o tcp,hard,intr,async,vers=4 192.168.1.100:/mnt/tempo/portages/cubiedev/packages /usr/portage/packages > > > mount -t nfs -o tcp,hard,intr,async,vers=4,rsize=4096,wsize=4096 192.168.1.100:/var/tmp/portage/cubie /var/tmp/portage/ > > > mount -t nfs -o tcp,hard,intr,async,rsize=4096,wsize=4096 192.168.1.100:/mnt/tempo/cubie/local_kernel /usr/src/ > > > > > > It's always the last which fail, but strangely inverting the two last > > > made everything ok. > > > > Thanks for more info and the debug data. I still was not able to reproduce > > the issue but after pondering my head on this for some time I have found a > > bug in NFS conversion which can possibly cause the behavior you observe. > > Does the attached patch fix the problem for you? > > > > If it does not, can you also post /proc/mounts and /etc/exports from you > > NFS server? > > > > This patch fix the issue Thanks for testing! I'll send the fix to Jens, hopefully it will go in still during this merge window. Honza
From 3367ba6af234038874d0b8e0a1638d3451ee9b4d Mon Sep 17 00:00:00 2001 From: Jan Kara <jack@suse.cz> Date: Wed, 3 May 2017 13:02:34 +0200 Subject: [PATCH] nfs: Fix bdi handling for cloned superblocks In commit 0d3b12584972 "nfs: Convert to separately allocated bdi" I have wrongly cloned bdi reference in nfs_clone_super(). Further inspection has shown that originally the code was actually allocating a new bdi (in ->clone_server callback) which was later registered in nfs_fs_mount_common() and used for sb->s_bdi in nfs_initialise_sb(). This could later result in bdi for the original superblock not getting unregistered when that superblock got shutdown (as the cloned sb still held bdi reference) and later when a new superblock was created under the same anonymous device number, a clash in sysfs has happened on bdi registration: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 10284 at /linux-next/fs/sysfs/dir.c:31 sysfs_warn_dup+0x64/0x74 sysfs: cannot create duplicate filename '/devices/virtual/bdi/0:32' Modules linked in: axp20x_usb_power gpio_axp209 nvmem_sunxi_sid sun4i_dma sun4i_ss virt_dma CPU: 1 PID: 10284 Comm: mount.nfs Not tainted 4.11.0-rc4+ #14 Hardware name: Allwinner sun7i (A20) Family [<c010f19c>] (unwind_backtrace) from [<c010bc74>] (show_stack+0x10/0x14) [<c010bc74>] (show_stack) from [<c03c6e24>] (dump_stack+0x78/0x8c) [<c03c6e24>] (dump_stack) from [<c0122200>] (__warn+0xe8/0x100) [<c0122200>] (__warn) from [<c0122250>] (warn_slowpath_fmt+0x38/0x48) [<c0122250>] (warn_slowpath_fmt) from [<c02ac178>] (sysfs_warn_dup+0x64/0x74) [<c02ac178>] (sysfs_warn_dup) from [<c02ac254>] (sysfs_create_dir_ns+0x84/0x94) [<c02ac254>] (sysfs_create_dir_ns) from [<c03c8b8c>] (kobject_add_internal+0x9c/0x2ec) [<c03c8b8c>] (kobject_add_internal) from [<c03c8e24>] (kobject_add+0x48/0x98) [<c03c8e24>] (kobject_add) from [<c048d75c>] (device_add+0xe4/0x5a0) [<c048d75c>] (device_add) from [<c048ddb4>] (device_create_groups_vargs+0xac/0xbc) [<c048ddb4>] (device_create_groups_vargs) from [<c048dde4>] (device_create_vargs+0x20/0x28) [<c048dde4>] (device_create_vargs) from [<c02075c8>] (bdi_register_va+0x44/0xfc) [<c02075c8>] (bdi_register_va) from [<c023d378>] (super_setup_bdi_name+0x48/0xa4) [<c023d378>] (super_setup_bdi_name) from [<c0312ef4>] (nfs_fill_super+0x1a4/0x204) [<c0312ef4>] (nfs_fill_super) from [<c03133f0>] (nfs_fs_mount_common+0x140/0x1e8) [<c03133f0>] (nfs_fs_mount_common) from [<c03335cc>] (nfs4_remote_mount+0x50/0x58) [<c03335cc>] (nfs4_remote_mount) from [<c023ef98>] (mount_fs+0x14/0xa4) [<c023ef98>] (mount_fs) from [<c025cba0>] (vfs_kern_mount+0x54/0x128) [<c025cba0>] (vfs_kern_mount) from [<c033352c>] (nfs_do_root_mount+0x80/0xa0) [<c033352c>] (nfs_do_root_mount) from [<c0333818>] (nfs4_try_mount+0x28/0x3c) [<c0333818>] (nfs4_try_mount) from [<c0313874>] (nfs_fs_mount+0x2cc/0x8c4) [<c0313874>] (nfs_fs_mount) from [<c023ef98>] (mount_fs+0x14/0xa4) [<c023ef98>] (mount_fs) from [<c025cba0>] (vfs_kern_mount+0x54/0x128) [<c025cba0>] (vfs_kern_mount) from [<c02600f0>] (do_mount+0x158/0xc7c) [<c02600f0>] (do_mount) from [<c0260f98>] (SyS_mount+0x8c/0xb4) [<c0260f98>] (SyS_mount) from [<c0107840>] (ret_fast_syscall+0x0/0x3c) Fix the problem by always creating new bdi for a superblock as we used to do. Reported-by: Corentin Labbe <clabbe.montjoie@gmail.com> Fixes: 0d3b12584972ce5781179ad3f15cca3cdb5cae05 Signed-off-by: Jan Kara <jack@suse.cz> --- fs/nfs/internal.h | 6 +++--- fs/nfs/super.c | 28 ++++++++++------------------ 2 files changed, 13 insertions(+), 21 deletions(-) diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h index 9dc65d7ae754..7b38fedb7e03 100644 --- a/fs/nfs/internal.h +++ b/fs/nfs/internal.h @@ -139,7 +139,7 @@ struct nfs_mount_request { }; struct nfs_mount_info { - int (*fill_super)(struct super_block *, struct nfs_mount_info *); + void (*fill_super)(struct super_block *, struct nfs_mount_info *); int (*set_security)(struct super_block *, struct dentry *, struct nfs_mount_info *); struct nfs_parsed_mount_data *parsed; struct nfs_clone_mount *cloned; @@ -407,7 +407,7 @@ struct dentry *nfs_fs_mount(struct file_system_type *, int, const char *, void * struct dentry * nfs_xdev_mount_common(struct file_system_type *, int, const char *, struct nfs_mount_info *); void nfs_kill_super(struct super_block *); -int nfs_fill_super(struct super_block *, struct nfs_mount_info *); +void nfs_fill_super(struct super_block *, struct nfs_mount_info *); extern struct rpc_stat nfs_rpcstat; @@ -458,7 +458,7 @@ extern void nfs_read_prepare(struct rpc_task *task, void *calldata); extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio); /* super.c */ -int nfs_clone_super(struct super_block *, struct nfs_mount_info *); +void nfs_clone_super(struct super_block *, struct nfs_mount_info *); void nfs_umount_begin(struct super_block *); int nfs_statfs(struct dentry *, struct kstatfs *); int nfs_show_options(struct seq_file *, struct dentry *); diff --git a/fs/nfs/super.c b/fs/nfs/super.c index dc69314d455e..2f3822a4a7d5 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -2321,11 +2321,10 @@ inline void nfs_initialise_sb(struct super_block *sb) /* * Finish setting up an NFS2/3 superblock */ -int nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info) +void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info) { struct nfs_parsed_mount_data *data = mount_info->parsed; struct nfs_server *server = NFS_SB(sb); - int ret; sb->s_blocksize_bits = 0; sb->s_blocksize = 0; @@ -2343,21 +2342,13 @@ int nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info) } nfs_initialise_sb(sb); - - ret = super_setup_bdi_name(sb, "%u:%u", MAJOR(server->s_dev), - MINOR(server->s_dev)); - if (ret) - return ret; - sb->s_bdi->ra_pages = server->rpages * NFS_MAX_READAHEAD; - return 0; - } EXPORT_SYMBOL_GPL(nfs_fill_super); /* * Finish setting up a cloned NFS2/3/4 superblock */ -int nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info) +void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info) { const struct super_block *old_sb = mount_info->cloned->sb; struct nfs_server *server = NFS_SB(sb); @@ -2377,10 +2368,6 @@ int nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info) } nfs_initialise_sb(sb); - - sb->s_bdi = bdi_get(old_sb->s_bdi); - - return 0; } static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags) @@ -2600,14 +2587,19 @@ struct dentry *nfs_fs_mount_common(struct nfs_server *server, nfs_free_server(server); server = NULL; } else { + error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev), + MINOR(server->s_dev)); + if (error) { + mntroot = ERR_PTR(error); + goto error_splat_super; + } + s->s_bdi->ra_pages = server->rpages * NFS_MAX_READAHEAD; server->super = s; } if (!s->s_root) { /* initial superblock/root creation */ - error = mount_info->fill_super(s, mount_info); - if (error) - goto error_splat_super; + mount_info->fill_super(s, mount_info); nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned); } -- 2.12.0