src/sys/fs/devfs/devfs_devs.c, branch releng/13.4 FreeBSD source tree devfs: add integrity asserts for cdevp_list 2023-09-28T01:29:52+00:00 Jason A. Harmening jah@FreeBSD.org 2023-09-19T13:44:34+00:00 ee596061e5a5952f1ddc68627492fbe94af8344b It's possible for misuse of cdev KPIs or for bugs in devfs itself to result in e.g. a cdev object's container being freed while still on the global list used to populate each devfs mount; see PR 273418 for a recent example. Since a node may be marked inactive well before it is reaped from the list, add a new flag solely to track list membership, and employ it in some basic list integrity assertions to catch bad actors. Discussed with: kib, mjg (cherry picked from commit 67864268da53b792836f13be10299de8cd62997e) 
It's possible for misuse of cdev KPIs or for bugs in devfs itself to
result in e.g. a cdev object's container being freed while still on the
global list used to populate each devfs mount; see PR 273418 for a
recent example.

Since a node may be marked inactive well before it is reaped from the
list, add a new flag solely to track list membership, and employ it in
some basic list integrity assertions to catch bad actors.

Discussed with:	kib, mjg

(cherry picked from commit 67864268da53b792836f13be10299de8cd62997e)
sys: Remove $FreeBSD$: two-line .h pattern 2023-08-23T17:43:20+00:00 Warner Losh imp@FreeBSD.org 2023-08-22T01:31:02+00:00 f8167e0404dab9ffeaca95853dd237ab7c587f82 Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/ Similar commit in current: (cherry picked from commit 95ee2897e98f) 
Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

Similar commit in current:
(cherry picked from commit 95ee2897e98f)
spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD 2023-07-25T15:13:49+00:00 Warner Losh imp@FreeBSD.org 2023-05-10T15:40:58+00:00 caa41f641755c935b036e17440a3b49329c904ed The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch up to that fact and revert to their recommended match of BSD-2-Clause. Discussed with: pfg MFC After: 3 days Sponsored by: Netflix (cherry picked from commit 4d846d260e2b9a3d4d0a701462568268cbfe7a5b) 
The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with:		pfg
MFC After:		3 days
Sponsored by:		Netflix

(cherry picked from commit 4d846d260e2b9a3d4d0a701462568268cbfe7a5b)
devfs(4): defer freeing until we drop devmtx ("cdev") 2020-12-29T13:47:36+00:00 Edward Tomasz Napierala trasz@FreeBSD.org 2020-12-29T13:45:53+00:00 4ddb3cc5973b94b0502e1683accac87998235857 Before r332974 the old code would sometimes cause a rare lock order reversal against pagequeue, which looked roughly like this: witness_checkorder() __mtx_lock-flags() vm_page_alloc() uma_small_alloc() keg_alloc_slab() keg_fetch-slab() zone_fetch-slab() zone_import() zone_alloc_bucket() uma_zalloc_arg() bucket_alloc() uma_zfree_arg() free() devfs_metoo() devfs_populate_loop() devfs_populate() devfs_rioctl() VOP_IOCTL_APV() VOP_IOCTL() vn_ioctl() fo_ioctl() kern_ioctl() sys_ioctl() Since r332974 the original problem no longer exists, but it still makes sense to move things out of the - often congested - lock. Reviewed By: kib, markj Sponsored by: NetApp, Inc. Sponsored by: Klara, Inc. Differential Revision: https://reviews.freebsd.org/D27334 
Before r332974 the old code would sometimes cause a rare lock order
reversal against pagequeue, which looked roughly like this:

witness_checkorder()
__mtx_lock-flags()
vm_page_alloc()
uma_small_alloc()
keg_alloc_slab()
keg_fetch-slab()
zone_fetch-slab()
zone_import()
zone_alloc_bucket()
uma_zalloc_arg()
bucket_alloc()
uma_zfree_arg()
free()
devfs_metoo()
devfs_populate_loop()
devfs_populate()
devfs_rioctl()
VOP_IOCTL_APV()
VOP_IOCTL()
vn_ioctl()
fo_ioctl()
kern_ioctl()
sys_ioctl()

Since r332974 the original problem no longer exists, but it still
makes sense to move things out of the - often congested - lock.

Reviewed By:	kib, markj
Sponsored by:	NetApp, Inc.
Sponsored by:	Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D27334
fs: clean up empty lines in .c and .h files 2020-09-01T21:18:40+00:00 Mateusz Guzik mjg@FreeBSD.org 2020-09-01T21:18:40+00:00 586ee69f09c5060621486b34722a4a806581f93d 






devfs: Abstract locking assertions
2020-08-12T00:32:31+00:00

Conrad Meyer
cem@FreeBSD.org

2020-08-12T00:32:31+00:00

0ac9e27ba964b4d29ed180d5e546873de638822c

The conversion was largely mechanical: sed(1) with:

  -e 's|mtx_assert(&devmtx, MA_OWNED)|dev_lock_assert_locked()|g'
  -e 's|mtx_assert(&devmtx, MA_NOTOWNED)|dev_lock_assert_unlocked()|g'

The definitions of these abstractions in fs/devfs/devfs_int.h are the
only non-mechanical change.

No functional change.





The conversion was largely mechanical: sed(1) with:

  -e 's|mtx_assert(&devmtx, MA_OWNED)|dev_lock_assert_locked()|g'
  -e 's|mtx_assert(&devmtx, MA_NOTOWNED)|dev_lock_assert_unlocked()|g'

The definitions of these abstractions in fs/devfs/devfs_int.h are the
only non-mechanical change.

No functional change.







devfs: bool -> int
2020-08-10T11:46:39+00:00

Mateusz Guzik
mjg@FreeBSD.org

2020-08-10T11:46:39+00:00

ca423b858bf4800bb22963e8133b72499bb18d24

Fixes buildworld after r364069





Fixes buildworld after r364069







devfs: save on spurious relocking for devfs_populate
2020-08-10T10:36:43+00:00

Mateusz Guzik
mjg@FreeBSD.org

2020-08-10T10:36:43+00:00

7b19bddac8f6ae5a356ffbca80f087d3654b8363

Tested by:	pho





Tested by:	pho







Mark more nodes as CTLFLAG_MPSAFE or CTLFLAG_NEEDGIANT (17 of many)
2020-02-26T14:26:36+00:00

Pawel Biernacki
kaktus@FreeBSD.org

2020-02-26T14:26:36+00:00

7029da5c36f2d3cf6bb6c81bf551229f416399e8

r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.

This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.

Mark all obvious cases as MPSAFE.  All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT

Approved by:	kib (mentor, blanket)
Commented by:	kib, gallatin, melifaro
Differential Revision:	https://reviews.freebsd.org/D23718





r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.

This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.

Mark all obvious cases as MPSAFE.  All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT

Approved by:	kib (mentor, blanket)
Commented by:	kib, gallatin, melifaro
Differential Revision:	https://reviews.freebsd.org/D23718







vfs: drop the mostly unused flags argument from VOP_UNLOCK
2020-01-03T22:29:58+00:00

Mateusz Guzik
mjg@FreeBSD.org

2020-01-03T22:29:58+00:00

b249ce48ea5560afdcff57e72a9880b7d3132434

Filesystems which want to use it in limited capacity can employ the
VOP_UNLOCK_FLAGS macro.

Reviewed by:	kib (previous version)
Differential Revision:	https://reviews.freebsd.org/D21427





Filesystems which want to use it in limited capacity can employ the
VOP_UNLOCK_FLAGS macro.

Reviewed by:	kib (previous version)
Differential Revision:	https://reviews.freebsd.org/D21427