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Linux kernel
============
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There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
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When vgic_prune_ap_list() finds an interrupt that needs to be migrated
to a new VCPU, we should notify this VCPU of the pending interrupt,
since it requires immediate action.
Kick this VCPU once we have added the new IRQ to the list, but only
after dropping the locks.
Reported-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
While generating a message about guests probing for SVE/LORegions
is a useful debugging tool, considering it an error is slightly
over the top, as this is the only way the guest can find out
about the presence of the feature.
Let's turn these message into kvm_debug so that they can only
be seen if CONFIG_DYNAMIC_DEBUG, and kept quiet otherwise.
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Update my e-mail address to a working address.
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Before entering the guest, we check whether our VMID is still
part of the current generation. In order to avoid taking a lock,
we start with checking that the generation is still current, and
only if not current do we take the lock, recheck, and update the
generation and VMID.
This leaves open a small race: A vcpu can bump up the global
generation number as well as the VM's, but has not updated
the VMID itself yet.
At that point another vcpu from the same VM comes in, checks
the generation (and finds it not needing anything), and jumps
into the guest. At this point, we end-up with two vcpus belonging
to the same VM running with two different VMIDs. Eventually, the
VMID used by the second vcpu will get reassigned, and things will
really go wrong...
A simple solution would be to drop this initial check, and always take
the lock. This is likely to cause performance issues. A middle ground
is to convert the spinlock to a rwlock, and only take the read lock
on the fast path. If the check fails at that point, drop it and
acquire the write lock, rechecking the condition.
This ensures that the above scenario doesn't occur.
Cc: stable@vger.kernel.org
Reported-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Shannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Pull more btrfs updates from David Sterba:
"We have queued a few more fixes (error handling, log replay,
softlockup) and the rest is SPDX updates that touche almost all files
so the diffstat is long"
* tag 'for-4.17-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: Only check first key for committed tree blocks
btrfs: add SPDX header to Kconfig
btrfs: replace GPL boilerplate by SPDX -- sources
btrfs: replace GPL boilerplate by SPDX -- headers
Btrfs: fix loss of prealloc extents past i_size after fsync log replay
Btrfs: clean up resources during umount after trans is aborted
btrfs: Fix possible softlock on single core machines
Btrfs: bail out on error during replay_dir_deletes
Btrfs: fix NULL pointer dereference in log_dir_items
Pull cifs fixes from Steve French:
"SMB3 fixes, a few for stable, and some important cleanup work from
Ronnie of the smb3 transport code"
* tag '4.17-rc1SMB3-Fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: change validate_buf to validate_iov
cifs: remove rfc1002 hardcoded constants from cifs_discard_remaining_data()
cifs: Change SMB2_open to return an iov for the error parameter
cifs: add resp_buf_size to the mid_q_entry structure
smb3.11: replace a 4 with server->vals->header_preamble_size
cifs: replace a 4 with server->vals->header_preamble_size
cifs: add pdu_size to the TCP_Server_Info structure
SMB311: Improve checking of negotiate security contexts
SMB3: Fix length checking of SMB3.11 negotiate request
CIFS: add ONCE flag for cifs_dbg type
cifs: Use ULL suffix for 64-bit constant
SMB3: Log at least once if tree connect fails during reconnect
cifs: smb2pdu: Fix potential NULL pointer dereference
When looping btrfs/074 with many cpus (>= 8), it's possible to trigger
kernel warning due to first key verification:
[ 4239.523446] WARNING: CPU: 5 PID: 2381 at fs/btrfs/disk-io.c:460 btree_read_extent_buffer_pages+0x1ad/0x210
[ 4239.523830] Modules linked in:
[ 4239.524630] RIP: 0010:btree_read_extent_buffer_pages+0x1ad/0x210
[ 4239.527101] Call Trace:
[ 4239.527251] read_tree_block+0x42/0x70
[ 4239.527434] read_node_slot+0xd2/0x110
[ 4239.527632] push_leaf_right+0xad/0x1b0
[ 4239.527809] split_leaf+0x4ea/0x700
[ 4239.527988] ? leaf_space_used+0xbc/0xe0
[ 4239.528192] ? btrfs_set_lock_blocking_rw+0x99/0xb0
[ 4239.528416] btrfs_search_slot+0x8cc/0xa40
[ 4239.528605] btrfs_insert_empty_items+0x71/0xc0
[ 4239.528798] __btrfs_run_delayed_refs+0xa98/0x1680
[ 4239.529013] btrfs_run_delayed_refs+0x10b/0x1b0
[ 4239.529205] btrfs_commit_transaction+0x33/0xaf0
[ 4239.529445] ? start_transaction+0xa8/0x4f0
[ 4239.529630] btrfs_alloc_data_chunk_ondemand+0x1b0/0x4e0
[ 4239.529833] btrfs_check_data_free_space+0x54/0xa0
[ 4239.530045] btrfs_delalloc_reserve_space+0x25/0x70
[ 4239.531907] btrfs_direct_IO+0x233/0x3d0
[ 4239.532098] generic_file_direct_write+0xcb/0x170
[ 4239.532296] btrfs_file_write_iter+0x2bb/0x5f4
[ 4239.532491] aio_write+0xe2/0x180
[ 4239.532669] ? lock_acquire+0xac/0x1e0
[ 4239.532839] ? __might_fault+0x3e/0x90
[ 4239.533032] do_io_submit+0x594/0x860
[ 4239.533223] ? do_io_submit+0x594/0x860
[ 4239.533398] SyS_io_submit+0x10/0x20
[ 4239.533560] ? SyS_io_submit+0x10/0x20
[ 4239.533729] do_syscall_64+0x75/0x1d0
[ 4239.533979] entry_SYSCALL_64_after_hwframe+0x42/0xb7
[ 4239.534182] RIP: 0033:0x7f8519741697
The problem here is, at btree_read_extent_buffer_pages() we don't have
acquired read/write lock on that extent buffer, only basic info like
level/bytenr is reliable.
So race condition leads to such false alert.
However in current call site, it's impossible to acquire proper lock
without race window.
To fix the problem, we only verify first key for committed tree blocks
(whose generation is no larger than fs_info->last_trans_committed), so
the content of such tree blocks will not change and there is no need to
get read/write lock.
Reported-by: Nikolay Borisov <nborisov@suse.com>
Fixes: 581c1760415c ("btrfs: Validate child tree block's level and first key")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull SCSI fixes from James Bottomley:
"This is a set of minor (and safe changes) that didn't make the initial
pull request plus some bug fixes.
The status handling code is actually a running regression from the
previous merge window which had an incomplete fix (now reverted) and
most of the remaining bug fixes are for problems older than the
current merge window"
[ Side note: this merge also takes the base kernel git repository to 6+
million objects for the first time. Technically we hit it a couple of
merges ago already if you count all the tag objects, but now it
reaches 6M+ objects reachable from HEAD.
I was joking around that that's when I should switch to 5.0, because
3.0 happened at the 2M mark, and 4.0 happened at 4M objects. But
probably not, even if numerology is about as good a reason as any.
- Linus ]
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: devinfo: Add Microsoft iSCSI target to 1024 sector blacklist
scsi: cxgb4i: silence overflow warning in t4_uld_rx_handler()
scsi: dpt_i2o: Use after free in I2ORESETCMD ioctl
scsi: core: Make scsi_result_to_blk_status() recognize CONDITION MET
scsi: core: Rename __scsi_error_from_host_byte() into scsi_result_to_blk_status()
Revert "scsi: core: return BLK_STS_OK for DID_OK in __scsi_error_from_host_byte()"
scsi: aacraid: Insure command thread is not recursively stopped
scsi: qla2xxx: Correct setting of SAM_STAT_CHECK_CONDITION
scsi: qla2xxx: correctly shift host byte
scsi: qla2xxx: Fix race condition between iocb timeout and initialisation
scsi: qla2xxx: Avoid double completion of abort command
scsi: qla2xxx: Fix small memory leak in qla2x00_probe_one on probe failure
scsi: scsi_dh: Don't look for NULL devices handlers by name
scsi: core: remove redundant assignment to shost->use_blk_mq
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull more Kbuild updates from Masahiro Yamada:
- pass HOSTLDFLAGS when compiling single .c host programs
- build genksyms lexer and parser files instead of using shipped
versions
- rename *-asn1.[ch] to *.asn1.[ch] for suffix consistency
- let the top .gitignore globally ignore artifacts generated by flex,
bison, and asn1_compiler
- let the top Makefile globally clean artifacts generated by flex,
bison, and asn1_compiler
- use safer .SECONDARY marker instead of .PRECIOUS to prevent
intermediate files from being removed
- support -fmacro-prefix-map option to make __FILE__ a relative path
- fix # escaping to prepare for the future GNU Make release
- clean up deb-pkg by using debian tools instead of handrolled
source/changes generation
- improve rpm-pkg portability by supporting kernel-install as a
fallback of new-kernel-pkg
- extend Kconfig listnewconfig target to provide more information
* tag 'kbuild-v4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: extend output of 'listnewconfig'
kbuild: rpm-pkg: use kernel-install as a fallback for new-kernel-pkg
Kbuild: fix # escaping in .cmd files for future Make
kbuild: deb-pkg: split generating packaging and build
kbuild: use -fmacro-prefix-map to make __FILE__ a relative path
kbuild: mark $(targets) as .SECONDARY and remove .PRECIOUS markers
kbuild: rename *-asn1.[ch] to *.asn1.[ch]
kbuild: clean up *-asn1.[ch] patterns from top-level Makefile
.gitignore: move *-asn1.[ch] patterns to the top-level .gitignore
kbuild: add %.dtb.S and %.dtb to 'targets' automatically
kbuild: add %.lex.c and %.tab.[ch] to 'targets' automatically
genksyms: generate lexer and parser during build instead of shipping
kbuild: clean up *.lex.c and *.tab.[ch] patterns from top-level Makefile
.gitignore: move *.lex.c *.tab.[ch] patterns to the top-level .gitignore
kbuild: use HOSTLDFLAGS for single .c executables
The Windows Server 2016 iSCSI target doesn't work with the Linux kernel
initiator since the kernel started sending larger requests by default,
nor does it implement the block limits VPD page. Apply the sector limit
workaround for these targets.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Acked-by: KY Srinivasan <kys@microsoft.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
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