linux-stable.git/include/trace/events/sunrpc.h, branch linux-5.4.y Linux kernel stable tree SUNRPC: Fix general protection fault in trace_rpc_xdr_overflow() 2020-11-18T18:20:26+00:00 Chuck Lever chuck.lever@oracle.com 2020-10-23T14:41:07+00:00 dfcb33773877f31a40ba0583e622935ef105c90b [ Upstream commit d321ff589c16d8c2207485a6d7fbdb14e873d46e ] The TP_fast_assign() section is careful enough not to dereference xdr->rqst if it's NULL. The TP_STRUCT__entry section is not. Fixes: 5582863f450c ("SUNRPC: Add XDR overflow trace event") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit d321ff589c16d8c2207485a6d7fbdb14e873d46e ]

The TP_fast_assign() section is careful enough not to dereference
xdr->rqst if it's NULL. The TP_STRUCT__entry section is not.

Fixes: 5582863f450c ("SUNRPC: Add XDR overflow trace event")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
SUNRPC: Capture completion of all RPC tasks 2020-10-01T11:17:21+00:00 Chuck Lever chuck.lever@oracle.com 2019-11-20T21:25:52+00:00 3ce5297c0b40a01e8f1e2c4bf6bc2944ec21439f [ Upstream commit a264abad51d8ecb7954a2f6d9f1885b38daffc74 ] RPC tasks on the backchannel never invoke xprt_complete_rqst(), so there is no way to report their tk_status at completion. Also, any RPC task that exits via rpc_exit_task() before it is replied to will also disappear without a trace. Introduce a trace point that is symmetrical with rpc_task_begin that captures the termination status of each RPC task. Sample trace output for callback requests initiated on the server: kworker/u8:12-448 [003] 127.025240: rpc_task_end: task:50@3 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpc_exit_task kworker/u8:12-448 [002] 127.567310: rpc_task_end: task:51@3 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpc_exit_task kworker/u8:12-448 [001] 130.506817: rpc_task_end: task:52@3 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpc_exit_task Odd, though, that I never see trace_rpc_task_complete, either in the forward or backchannel. Should it be removed? Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit a264abad51d8ecb7954a2f6d9f1885b38daffc74 ]

RPC tasks on the backchannel never invoke xprt_complete_rqst(), so
there is no way to report their tk_status at completion. Also, any
RPC task that exits via rpc_exit_task() before it is replied to will
also disappear without a trace.

Introduce a trace point that is symmetrical with rpc_task_begin that
captures the termination status of each RPC task.

Sample trace output for callback requests initiated on the server:
   kworker/u8:12-448   [003]   127.025240: rpc_task_end:         task:50@3 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpc_exit_task
   kworker/u8:12-448   [002]   127.567310: rpc_task_end:         task:51@3 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpc_exit_task
   kworker/u8:12-448   [001]   130.506817: rpc_task_end:         task:52@3 flags=ASYNC|DYNAMIC|SOFT|SOFTCONN|SENT runstate=RUNNING|ACTIVE status=0 action=rpc_exit_task

Odd, though, that I never see trace_rpc_task_complete, either in the
forward or backchannel. Should it be removed?

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Merge tag 'nfs-for-5.2-1' of git://git.linux-nfs.org/projects/anna/linux-nfs 2019-05-09T21:33:15+00:00 Linus Torvalds torvalds@linux-foundation.org 2019-05-09T21:33:15+00:00 06cbd26d312edfe4a83ff541c23f8f866265eb24 Pull NFS client updates from Anna Schumaker: "Highlights include: Stable bugfixes: - Fall back to MDS if no deviceid is found rather than aborting # v4.11+ - NFS4: Fix v4.0 client state corruption when mount Features: - Much improved handling of soft mounts with NFS v4.0: - Reduce risk of false positive timeouts - Faster failover of reads and writes after a timeout - Added a "softerr" mount option to return ETIMEDOUT instead of EIO to the application after a timeout - Increase number of xprtrdma backchannel requests - Add additional xprtrdma tracepoints - Improved send completion batching for xprtrdma Other bugfixes and cleanups: - Return -EINVAL when NFS v4.2 is passed an invalid dedup mode - Reduce usage of GFP_ATOMIC pages in SUNRPC - Various minor NFS over RDMA cleanups and bugfixes - Use the correct container namespace for upcalls - Don't share superblocks between user namespaces - Various other container fixes - Make nfs_match_client() killable to prevent soft lockups - Don't mark all open state for recovery when handling recallable state revoked flag" * tag 'nfs-for-5.2-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (69 commits) SUNRPC: Rebalance a kref in auth_gss.c NFS: Fix a double unlock from nfs_match,get_client nfs: pass the correct prototype to read_cache_page NFSv4: don't mark all open state for recovery when handling recallable state revoked flag SUNRPC: Fix an error code in gss_alloc_msg() SUNRPC: task should be exit if encode return EKEYEXPIRED more times NFS4: Fix v4.0 client state corruption when mount PNFS fallback to MDS if no deviceid found NFS: make nfs_match_client killable lockd: Store the lockd client credential in struct nlm_host NFS: When mounting, don't share filesystems between different user namespaces NFS: Convert NFSv2 to use the container user namespace NFSv4: Convert the NFS client idmapper to use the container user namespace NFS: Convert NFSv3 to use the container user namespace SUNRPC: Use namespace of listening daemon in the client AUTH_GSS upcall SUNRPC: Use the client user namespace when encoding creds NFS: Store the credential of the mount process in the nfs_server SUNRPC: Cache cred of process creating the rpc_client xprtrdma: Remove stale comment xprtrdma: Update comments that reference ib_drain_qp ... 
Pull NFS client updates from Anna Schumaker:
 "Highlights include:

  Stable bugfixes:
   - Fall back to MDS if no deviceid is found rather than aborting   # v4.11+
   - NFS4: Fix v4.0 client state corruption when mount

  Features:
   - Much improved handling of soft mounts with NFS v4.0:
       - Reduce risk of false positive timeouts
       - Faster failover of reads and writes after a timeout
       - Added a "softerr" mount option to return ETIMEDOUT instead of
         EIO to the application after a timeout
   - Increase number of xprtrdma backchannel requests
   - Add additional xprtrdma tracepoints
   - Improved send completion batching for xprtrdma

  Other bugfixes and cleanups:
   - Return -EINVAL when NFS v4.2 is passed an invalid dedup mode
   - Reduce usage of GFP_ATOMIC pages in SUNRPC
   - Various minor NFS over RDMA cleanups and bugfixes
   - Use the correct container namespace for upcalls
   - Don't share superblocks between user namespaces
   - Various other container fixes
   - Make nfs_match_client() killable to prevent soft lockups
   - Don't mark all open state for recovery when handling recallable
     state revoked flag"

* tag 'nfs-for-5.2-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (69 commits)
  SUNRPC: Rebalance a kref in auth_gss.c
  NFS: Fix a double unlock from nfs_match,get_client
  nfs: pass the correct prototype to read_cache_page
  NFSv4: don't mark all open state for recovery when handling recallable state revoked flag
  SUNRPC: Fix an error code in gss_alloc_msg()
  SUNRPC: task should be exit if encode return EKEYEXPIRED more times
  NFS4: Fix v4.0 client state corruption when mount
  PNFS fallback to MDS if no deviceid found
  NFS: make nfs_match_client killable
  lockd: Store the lockd client credential in struct nlm_host
  NFS: When mounting, don't share filesystems between different user namespaces
  NFS: Convert NFSv2 to use the container user namespace
  NFSv4: Convert the NFS client idmapper to use the container user namespace
  NFS: Convert NFSv3 to use the container user namespace
  SUNRPC: Use namespace of listening daemon in the client AUTH_GSS upcall
  SUNRPC: Use the client user namespace when encoding creds
  NFS: Store the credential of the mount process in the nfs_server
  SUNRPC: Cache cred of process creating the rpc_client
  xprtrdma: Remove stale comment
  xprtrdma: Update comments that reference ib_drain_qp
  ...
Merge tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk 2019-05-07T16:18:12+00:00 Linus Torvalds torvalds@linux-foundation.org 2019-05-07T16:18:12+00:00 0968621917add2e0d60c8fbc4e24c670cb14319c Pull printk updates from Petr Mladek: - Allow state reset of printk_once() calls. - Prevent crashes when dereferencing invalid pointers in vsprintf(). Only the first byte is checked for simplicity. - Make vsprintf warnings consistent and inlined. - Treewide conversion of obsolete %pf, %pF to %ps, %pF printf modifiers. - Some clean up of vsprintf and test_printf code. * tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: lib/vsprintf: Make function pointer_string static vsprintf: Limit the length of inlined error messages vsprintf: Avoid confusion between invalid address and value vsprintf: Prevent crash when dereferencing invalid pointers vsprintf: Consolidate handling of unknown pointer specifiers vsprintf: Factor out %pO handler as kobject_string() vsprintf: Factor out %pV handler as va_format() vsprintf: Factor out %p[iI] handler as ip_addr_string() vsprintf: Do not check address of well-known strings vsprintf: Consistent %pK handling for kptr_restrict == 0 vsprintf: Shuffle restricted_pointer() printk: Tie printk_once / printk_deferred_once into .data.once for reset treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively lib/test_printf: Switch to bitmap_zalloc() 
Pull printk updates from Petr Mladek:

 - Allow state reset of printk_once() calls.

 - Prevent crashes when dereferencing invalid pointers in vsprintf().
   Only the first byte is checked for simplicity.

 - Make vsprintf warnings consistent and inlined.

 - Treewide conversion of obsolete %pf, %pF to %ps, %pF printf
   modifiers.

 - Some clean up of vsprintf and test_printf code.

* tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
  lib/vsprintf: Make function pointer_string static
  vsprintf: Limit the length of inlined error messages
  vsprintf: Avoid confusion between invalid address and value
  vsprintf: Prevent crash when dereferencing invalid pointers
  vsprintf: Consolidate handling of unknown pointer specifiers
  vsprintf: Factor out %pO handler as kobject_string()
  vsprintf: Factor out %pV handler as va_format()
  vsprintf: Factor out %p[iI] handler as ip_addr_string()
  vsprintf: Do not check address of well-known strings
  vsprintf: Consistent %pK handling for kptr_restrict == 0
  vsprintf: Shuffle restricted_pointer()
  printk: Tie printk_once / printk_deferred_once into .data.once for reset
  treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively
  lib/test_printf: Switch to bitmap_zalloc()
SUNRPC: Fix up tracking of timeouts 2019-04-25T18:18:13+00:00 Trond Myklebust trondmy@gmail.com 2019-04-07T17:58:50+00:00 5efd1876e61fe61b61e2d056782027c11bcd0982 Add a helper to ensure that debugfs and friends print out the correct current task timeout value. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> 
Add a helper to ensure that debugfs and friends print out the
correct current task timeout value.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
SUNRPC: Fix up task signalling 2019-04-25T18:18:12+00:00 Trond Myklebust trondmy@gmail.com 2019-04-07T17:58:44+00:00 ae67bd3821bb0a54d97e7883d211196637d487a9 The RPC_TASK_KILLED flag should really not be set from another context because it can clobber data in the struct task when task->tk_flags is changed non-atomically. Let's therefore swap out RPC_TASK_KILLED with an atomic flag, and add a function to set that flag and safely wake up the task. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> 
The RPC_TASK_KILLED flag should really not be set from another context
because it can clobber data in the struct task when task->tk_flags is
changed non-atomically.
Let's therefore swap out RPC_TASK_KILLED with an atomic flag, and add
a function to set that flag and safely wake up the task.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively 2019-04-09T12:19:06+00:00 Sakari Ailus sakari.ailus@linux.intel.com 2019-03-25T19:32:28+00:00 d75f773c86a2b8b7278e2c33343b46a4024bc002 %pF and %pf are functionally equivalent to %pS and %ps conversion specifiers. The former are deprecated, therefore switch the current users to use the preferred variant. The changes have been produced by the following command: git grep -l '%p[fF]' | grep -v '^\(tools\|Documentation\)/' | \ while read i; do perl -i -pe 's/%pf/%ps/g; s/%pF/%pS/g;' $i; done And verifying the result. Link: http://lkml.kernel.org/r/20190325193229.23390-1-sakari.ailus@linux.intel.com Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: linux-arm-kernel@lists.infradead.org Cc: sparclinux@vger.kernel.org Cc: linux-um@lists.infradead.org Cc: xen-devel@lists.xenproject.org Cc: linux-acpi@vger.kernel.org Cc: linux-pm@vger.kernel.org Cc: drbd-dev@lists.linbit.com Cc: linux-block@vger.kernel.org Cc: linux-mmc@vger.kernel.org Cc: linux-nvdimm@lists.01.org Cc: linux-pci@vger.kernel.org Cc: linux-scsi@vger.kernel.org Cc: linux-btrfs@vger.kernel.org Cc: linux-f2fs-devel@lists.sourceforge.net Cc: linux-mm@kvack.org Cc: ceph-devel@vger.kernel.org Cc: netdev@vger.kernel.org Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Acked-by: David Sterba <dsterba@suse.com> (for btrfs) Acked-by: Mike Rapoport <rppt@linux.ibm.com> (for mm/memblock.c) Acked-by: Bjorn Helgaas <bhelgaas@google.com> (for drivers/pci) Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com> 
%pF and %pf are functionally equivalent to %pS and %ps conversion
specifiers. The former are deprecated, therefore switch the current users
to use the preferred variant.

The changes have been produced by the following command:

	git grep -l '%p[fF]' | grep -v '^\(tools\|Documentation\)/' | \
	while read i; do perl -i -pe 's/%pf/%ps/g; s/%pF/%pS/g;' $i; done

And verifying the result.

Link: http://lkml.kernel.org/r/20190325193229.23390-1-sakari.ailus@linux.intel.com
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: sparclinux@vger.kernel.org
Cc: linux-um@lists.infradead.org
Cc: xen-devel@lists.xenproject.org
Cc: linux-acpi@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: drbd-dev@lists.linbit.com
Cc: linux-block@vger.kernel.org
Cc: linux-mmc@vger.kernel.org
Cc: linux-nvdimm@lists.01.org
Cc: linux-pci@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: linux-btrfs@vger.kernel.org
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: linux-mm@kvack.org
Cc: ceph-devel@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: David Sterba <dsterba@suse.com> (for btrfs)
Acked-by: Mike Rapoport <rppt@linux.ibm.com> (for mm/memblock.c)
Acked-by: Bjorn Helgaas <bhelgaas@google.com> (for drivers/pci)
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
fix null pointer deref in tracepoints in back channel 2019-03-12T20:01:39+00:00 Olga Kornievskaia kolga@netapp.com 2019-03-12T16:06:35+00:00 f87b543af45ea217fa1d000483f9a40944c1ff73 Backchannel doesn't have the rq_task->tk_clientid pointer set. Otherwise can lead to the following oops: ocalhost login: [ 111.385319] BUG: unable to handle kernel NULL pointer dereference at 0000000000000004 [ 111.388073] #PF error: [normal kernel read fault] [ 111.389452] PGD 80000000290d8067 P4D 80000000290d8067 PUD 75f25067 PMD 0 [ 111.391224] Oops: 0000 [#1] SMP PTI [ 111.392151] CPU: 0 PID: 3533 Comm: NFSv4 callback Not tainted 5.0.0-rc7+ #1 [ 111.393787] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015 [ 111.396340] RIP: 0010:trace_event_raw_event_xprt_enq_xmit+0x6f/0xf0 [sunrpc] [ 111.397974] Code: 00 00 00 48 89 ee 48 89 e7 e8 bd 0a 85 d7 48 85 c0 74 4a 41 0f b7 94 24 e0 00 00 00 48 89 e7 89 50 08 49 8b 94 24 a8 00 00 00 <8b> 52 04 89 50 0c 49 8b 94 24 c0 00 00 00 8b 92 a8 00 00 00 0f ca [ 111.402215] RSP: 0018:ffffb98743263cf8 EFLAGS: 00010286 [ 111.403406] RAX: ffffa0890fc3bc88 RBX: 0000000000000003 RCX: 0000000000000000 [ 111.405057] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb98743263cf8 [ 111.406656] RBP: ffffa0896f5368f0 R08: 0000000000000246 R09: 0000000000000000 [ 111.408437] R10: ffffe19b01c01500 R11: 0000000000000000 R12: ffffa08977d28a00 [ 111.410210] R13: 0000000000000004 R14: ffffa089315303f0 R15: ffffa08931530000 [ 111.411856] FS: 0000000000000000(0000) GS:ffffa0897bc00000(0000) knlGS:0000000000000000 [ 111.413699] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 111.415068] CR2: 0000000000000004 CR3: 000000002ac90004 CR4: 00000000001606f0 [ 111.416745] Call Trace: [ 111.417339] xprt_request_enqueue_transmit+0x2b6/0x4a0 [sunrpc] [ 111.418709] ? rpc_task_need_encode+0x40/0x40 [sunrpc] [ 111.419957] call_bc_transmit+0xd5/0x170 [sunrpc] [ 111.421067] __rpc_execute+0x7e/0x3f0 [sunrpc] [ 111.422177] rpc_run_bc_task+0x78/0xd0 [sunrpc] [ 111.423212] bc_svc_process+0x281/0x340 [sunrpc] [ 111.424325] nfs41_callback_svc+0x130/0x1c0 [nfsv4] [ 111.425430] ? remove_wait_queue+0x60/0x60 [ 111.426398] kthread+0xf5/0x130 [ 111.427155] ? nfs_callback_authenticate+0x50/0x50 [nfsv4] [ 111.428388] ? kthread_bind+0x10/0x10 [ 111.429270] ret_from_fork+0x1f/0x30 localhost login: [ 467.462259] BUG: unable to handle kernel NULL pointer dereference at 0000000000000004 [ 467.464411] #PF error: [normal kernel read fault] [ 467.465445] PGD 80000000728c1067 P4D 80000000728c1067 PUD 728c0067 PMD 0 [ 467.466980] Oops: 0000 [#1] SMP PTI [ 467.467759] CPU: 0 PID: 3517 Comm: NFSv4 callback Not tainted 5.0.0-rc7+ #1 [ 467.469393] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015 [ 467.471840] RIP: 0010:trace_event_raw_event_xprt_transmit+0x7c/0xf0 [sunrpc] [ 467.473392] Code: f6 48 85 c0 74 4b 49 8b 94 24 98 00 00 00 48 89 e7 0f b7 92 e0 00 00 00 89 50 08 49 8b 94 24 98 00 00 00 48 8b 92 a8 00 00 00 <8b> 52 04 89 50 0c 41 8b 94 24 a8 00 00 00 0f ca 89 50 10 41 8b 94 [ 467.477605] RSP: 0018:ffffabe7434fbcd0 EFLAGS: 00010282 [ 467.478793] RAX: ffff99720fc3bce0 RBX: 0000000000000003 RCX: 0000000000000000 [ 467.480409] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffabe7434fbcd0 [ 467.482011] RBP: ffff99726f631948 R08: 0000000000000246 R09: 0000000000000000 [ 467.483591] R10: 0000000070000000 R11: 0000000000000000 R12: ffff997277dfcc00 [ 467.485226] R13: 0000000000000000 R14: 0000000000000000 R15: ffff99722fecdca8 [ 467.486830] FS: 0000000000000000(0000) GS:ffff99727bc00000(0000) knlGS:0000000000000000 [ 467.488596] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 467.489931] CR2: 0000000000000004 CR3: 00000000270e6006 CR4: 00000000001606f0 [ 467.491559] Call Trace: [ 467.492128] xprt_transmit+0x303/0x3f0 [sunrpc] [ 467.493143] ? rpc_task_need_encode+0x40/0x40 [sunrpc] [ 467.494328] call_bc_transmit+0x49/0x170 [sunrpc] [ 467.495379] __rpc_execute+0x7e/0x3f0 [sunrpc] [ 467.496451] rpc_run_bc_task+0x78/0xd0 [sunrpc] [ 467.497467] bc_svc_process+0x281/0x340 [sunrpc] [ 467.498507] nfs41_callback_svc+0x130/0x1c0 [nfsv4] [ 467.499751] ? remove_wait_queue+0x60/0x60 [ 467.500686] kthread+0xf5/0x130 [ 467.501438] ? nfs_callback_authenticate+0x50/0x50 [nfsv4] [ 467.502640] ? kthread_bind+0x10/0x10 [ 467.503454] ret_from_fork+0x1f/0x30 Signed-off-by: Olga Kornievskaia <kolga@netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> 
Backchannel doesn't have the rq_task->tk_clientid pointer set.

Otherwise can lead to the following oops:
ocalhost login: [  111.385319] BUG: unable to handle kernel NULL pointer dereference at 0000000000000004
[  111.388073] #PF error: [normal kernel read fault]
[  111.389452] PGD 80000000290d8067 P4D 80000000290d8067 PUD 75f25067 PMD 0
[  111.391224] Oops: 0000 [#1] SMP PTI
[  111.392151] CPU: 0 PID: 3533 Comm: NFSv4 callback Not tainted 5.0.0-rc7+ #1
[  111.393787] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015
[  111.396340] RIP: 0010:trace_event_raw_event_xprt_enq_xmit+0x6f/0xf0 [sunrpc]
[  111.397974] Code: 00 00 00 48 89 ee 48 89 e7 e8 bd 0a 85 d7 48 85 c0 74 4a 41 0f b7 94 24 e0 00 00 00 48 89 e7 89 50 08 49 8b 94 24 a8 00 00 00 <8b> 52 04 89 50 0c 49 8b 94 24 c0 00 00 00 8b 92 a8 00 00 00 0f ca
[  111.402215] RSP: 0018:ffffb98743263cf8 EFLAGS: 00010286
[  111.403406] RAX: ffffa0890fc3bc88 RBX: 0000000000000003 RCX: 0000000000000000
[  111.405057] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb98743263cf8
[  111.406656] RBP: ffffa0896f5368f0 R08: 0000000000000246 R09: 0000000000000000
[  111.408437] R10: ffffe19b01c01500 R11: 0000000000000000 R12: ffffa08977d28a00
[  111.410210] R13: 0000000000000004 R14: ffffa089315303f0 R15: ffffa08931530000
[  111.411856] FS:  0000000000000000(0000) GS:ffffa0897bc00000(0000) knlGS:0000000000000000
[  111.413699] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  111.415068] CR2: 0000000000000004 CR3: 000000002ac90004 CR4: 00000000001606f0
[  111.416745] Call Trace:
[  111.417339]  xprt_request_enqueue_transmit+0x2b6/0x4a0 [sunrpc]
[  111.418709]  ? rpc_task_need_encode+0x40/0x40 [sunrpc]
[  111.419957]  call_bc_transmit+0xd5/0x170 [sunrpc]
[  111.421067]  __rpc_execute+0x7e/0x3f0 [sunrpc]
[  111.422177]  rpc_run_bc_task+0x78/0xd0 [sunrpc]
[  111.423212]  bc_svc_process+0x281/0x340 [sunrpc]
[  111.424325]  nfs41_callback_svc+0x130/0x1c0 [nfsv4]
[  111.425430]  ? remove_wait_queue+0x60/0x60
[  111.426398]  kthread+0xf5/0x130
[  111.427155]  ? nfs_callback_authenticate+0x50/0x50 [nfsv4]
[  111.428388]  ? kthread_bind+0x10/0x10
[  111.429270]  ret_from_fork+0x1f/0x30

localhost login: [  467.462259] BUG: unable to handle kernel NULL pointer dereference at 0000000000000004
[  467.464411] #PF error: [normal kernel read fault]
[  467.465445] PGD 80000000728c1067 P4D 80000000728c1067 PUD 728c0067 PMD 0
[  467.466980] Oops: 0000 [#1] SMP PTI
[  467.467759] CPU: 0 PID: 3517 Comm: NFSv4 callback Not tainted 5.0.0-rc7+ #1
[  467.469393] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015
[  467.471840] RIP: 0010:trace_event_raw_event_xprt_transmit+0x7c/0xf0 [sunrpc]
[  467.473392] Code: f6 48 85 c0 74 4b 49 8b 94 24 98 00 00 00 48 89 e7 0f b7 92 e0 00 00 00 89 50 08 49 8b 94 24 98 00 00 00 48 8b 92 a8 00 00 00 <8b> 52 04 89 50 0c 41 8b 94 24 a8 00 00 00 0f ca 89 50 10 41 8b 94
[  467.477605] RSP: 0018:ffffabe7434fbcd0 EFLAGS: 00010282
[  467.478793] RAX: ffff99720fc3bce0 RBX: 0000000000000003 RCX: 0000000000000000
[  467.480409] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffabe7434fbcd0
[  467.482011] RBP: ffff99726f631948 R08: 0000000000000246 R09: 0000000000000000
[  467.483591] R10: 0000000070000000 R11: 0000000000000000 R12: ffff997277dfcc00
[  467.485226] R13: 0000000000000000 R14: 0000000000000000 R15: ffff99722fecdca8
[  467.486830] FS:  0000000000000000(0000) GS:ffff99727bc00000(0000) knlGS:0000000000000000
[  467.488596] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  467.489931] CR2: 0000000000000004 CR3: 00000000270e6006 CR4: 00000000001606f0
[  467.491559] Call Trace:
[  467.492128]  xprt_transmit+0x303/0x3f0 [sunrpc]
[  467.493143]  ? rpc_task_need_encode+0x40/0x40 [sunrpc]
[  467.494328]  call_bc_transmit+0x49/0x170 [sunrpc]
[  467.495379]  __rpc_execute+0x7e/0x3f0 [sunrpc]
[  467.496451]  rpc_run_bc_task+0x78/0xd0 [sunrpc]
[  467.497467]  bc_svc_process+0x281/0x340 [sunrpc]
[  467.498507]  nfs41_callback_svc+0x130/0x1c0 [nfsv4]
[  467.499751]  ? remove_wait_queue+0x60/0x60
[  467.500686]  kthread+0xf5/0x130
[  467.501438]  ? nfs_callback_authenticate+0x50/0x50 [nfsv4]
[  467.502640]  ? kthread_bind+0x10/0x10
[  467.503454]  ret_from_fork+0x1f/0x30

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
SUNRPC: Introduce rpc_prepare_reply_pages() 2019-02-14T15:04:37+00:00 Chuck Lever chuck.lever@oracle.com 2019-02-11T16:25:20+00:00 cf500bac8fd48b57f38ece890235923d4ed5ee91 prepare_reply_buffer() and its NFSv4 equivalents expose the details of the RPC header and the auth slack values to upper layer consumers, creating a layering violation, and duplicating code. Remedy these issues by adding a new RPC client API that hides those details from upper layers in a common helper function. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> 
prepare_reply_buffer() and its NFSv4 equivalents expose the details
of the RPC header and the auth slack values to upper layer
consumers, creating a layering violation, and duplicating code.

Remedy these issues by adding a new RPC client API that hides those
details from upper layers in a common helper function.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
SUNRPC: Introduce trace points in rpc_auth_gss.ko 2019-02-14T14:20:40+00:00 Chuck Lever chuck.lever@oracle.com 2019-02-11T16:25:04+00:00 0c77668ddb4e7bdfbca462c6185d154d0b8889ae Add infrastructure for trace points in the RPC_AUTH_GSS kernel module, and add a few sample trace points. These report exceptional or unexpected events, and observe the assignment of GSS sequence numbers. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> 
Add infrastructure for trace points in the RPC_AUTH_GSS kernel
module, and add a few sample trace points. These report exceptional
or unexpected events, and observe the assignment of GSS sequence
numbers.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>