kernel.git/include/trace/events/afs.h, branch linux-5.4.y

afs: Fix tracepoint string placement with built-in AFS

2021-07-28T11:30:58Z

[ Upstream commit 6c881ca0b3040f3e724eae513117ba4ddef86057 ] To quote Alexey[1]: I was adding custom tracepoint to the kernel, grabbed full F34 kernel .config, disabled modules and booted whole shebang as VM kernel. Then did perf record -a -e ... It crashed: general protection fault, probably for non-canonical address 0x435f5346592e4243: 0000 [#1] SMP PTI CPU: 1 PID: 842 Comm: cat Not tainted 5.12.6+ #26 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014 RIP: 0010:t_show+0x22/0xd0 Then reproducer was narrowed to # cat /sys/kernel/tracing/printk_formats Original F34 kernel with modules didn't crash. So I started to disable options and after disabling AFS everything started working again. The root cause is that AFS was placing char arrays content into a section full of _pointers_ to strings with predictable consequences. Non canonical address 435f5346592e4243 is "CB.YFS_" which came from CM_NAME macro. Steps to reproduce: CONFIG_AFS=y CONFIG_TRACING=y # cat /sys/kernel/tracing/printk_formats Fix this by the following means: (1) Add enum->string translation tables in the event header with the AFS and YFS cache/callback manager operations listed by RPC operation ID. (2) Modify the afs_cb_call tracepoint to print the string from the translation table rather than using the string at the afs_call name pointer. (3) Switch translation table depending on the service we're being accessed as (AFS or YFS) in the tracepoint print clause. Will this cause problems to userspace utilities? Note that the symbolic representation of the YFS service ID isn't available to this header, so I've put it in as a number. I'm not sure if this is the best way to do this. (4) Remove the name wrangling (CM_NAME) macro and put the names directly into the afs_call_type structs in cmservice.c. Fixes: 8e8d7f13b6d5a9 ("afs: Add some tracepoints") Reported-by: Alexey Dobriyan (SK hynix) Signed-off-by: David Howells Reviewed-by: Steven Rostedt (VMware) Reviewed-by: Marc Dionne cc: Andrew Morton cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/YLAXfvZ+rObEOdc%2F@localhost.localdomain/ [1] Link: https://lore.kernel.org/r/643721.1623754699@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/162430903582.2896199.6098150063997983353.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/162609463957.3133237.15916579353149746363.stgit@warthog.procyon.org.uk/ # v1 (repost) Link: https://lore.kernel.org/r/162610726860.3408253.445207609466288531.stgit@warthog.procyon.org.uk/ # v2 Signed-off-by: Sasha Levin

afs: Fix some tracing details

2020-04-01T09:02:08Z

commit 4636cf184d6d9a92a56c2554681ea520dd4fe49a upstream. Fix a couple of tracelines to indicate the usage count after the atomic op, not the usage count before it to be consistent with other afs and rxrpc trace lines. Change the wording of the afs_call_trace_work trace ID label from "WORK" to "QUEUE" to reflect the fact that it's queueing work, not doing work. Fixes: 341f741f04be ("afs: Refcount the afs_call struct") Signed-off-by: David Howells Signed-off-by: Greg Kroah-Hartman

afs: Fix use-after-loss-of-ref

2020-01-17T18:48:41Z

commit 40a708bd622b78582ae3d280de29b09b50bd04c0 upstream. afs_lookup() has a tracepoint to indicate the outcome of d_splice_alias(), passing it the inode to retrieve the fid from. However, the function gave up its ref on that inode when it called d_splice_alias(), which may have failed and dropped the inode. Fix this by caching the fid. Fixes: 80548b03991f ("afs: Add more tracepoints") Reported-by: Al Viro Signed-off-by: David Howells Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

Merge tag 'afs-next-20190628' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

2019-07-11T03:55:33Z

Pull afs updates from David Howells: "A set of minor changes for AFS: - Remove an unnecessary check in afs_unlink() - Add a tracepoint for tracking callback management - Add a tracepoint for afs_server object usage - Use struct_size() - Add mappings for AFS UAE abort codes to Linux error codes, using symbolic names rather than hex numbers in the .c file" * tag 'afs-next-20190628' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: afs: Add support for the UAE error table fs/afs: use struct_size() in kzalloc() afs: Trace afs_server usage afs: Add some callback management tracepoints afs: afs_unlink() doesn't need to check dentry->d_inode

afs: Trace afs_server usage

2019-06-20T17:12:17Z

Add a tracepoint (afs_server) to track the afs_server object usage count. Signed-off-by: David Howells

afs: Add some callback management tracepoints

2019-06-20T17:12:16Z

Add a couple of tracepoints to track callback management: (1) afs_cb_miss - Logs when we were unable to apply a callback, either due to the inode being discarded or due to a competing thread applying a callback first. (2) afs_cb_break - Logs when we attempted to clear the noted callback promise, either due to the server explicitly breaking the callback, the callback promise lapsing or a local event obsoleting it. Signed-off-by: David Howells

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36

2019-05-24T15:27:11Z

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public licence as published by the free software foundation either version 2 of the licence or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 114 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Kate Stewart Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520170857.552531963@linutronix.de Signed-off-by: Greg Kroah-Hartman

afs: implement acl setting

2019-05-07T15:48:44Z

Implements the setting of ACLs in AFS by means of setting the afs.acl extended attribute on the file. Signed-off-by: Joe Gorse Signed-off-by: David Howells

afs: Get an AFS3 ACL as an xattr

2019-05-07T15:48:44Z

Implement an xattr on AFS files called "afs.acl" that retrieves a file's ACL. It returns the raw AFS3 ACL from the result of calling FS.FetchACL, leaving any interpretation to userspace. Note that whilst YFS servers will respond to FS.FetchACL, this will render a more-advanced YFS ACL down. Use "afs.yfs.acl" instead for that. Signed-off-by: David Howells

afs: Provide mount-time configurable byte-range file locking emulation

2019-04-25T13:26:52Z

Provide byte-range file locking emulation that can be configured at mount time to one of four modes: (1) flock=local. Locking is done locally only and no reference is made to the server. (2) flock=openafs. Byte-range locking is done locally only; whole-file locking is done with reference to the server. Whole-file locks cannot be upgraded unless the client holds an exclusive lock. (3) flock=strict. Byte-range and whole-file locking both require a sufficient whole-file lock on the server. (4) flock=write. As strict, but the client always gets an exclusive whole-file lock on the server. Signed-off-by: David Howells