Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
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.
code
Clone this repository
https://tangled.org/tjh.dev/kernel
git@gordian.tjh.dev:tjh.dev/kernel
For self-hosted knots, clone URLs may differ based on your setup.
Pull Xtensa fixes from Max Filippov:
- fix __sync_fetch_and_{and,or}_4 declarations to avoid build warning
- update *pos in cpuinfo_op.next to avoid runtime warning
- use for_each_set_bit in xtensa_pmu_irq_handler instead of open-coding
it
* tag 'xtensa-20200712' of git://github.com/jcmvbkbc/linux-xtensa:
xtensa: simplify xtensa_pmu_irq_handler
xtensa: update *pos in cpuinfo_op.next
xtensa: fix __sync_fetch_and_{and,or}_4 declarations
Pull io_uring fixes from Jens Axboe:
"Two late fixes again:
- Fix missing msg_name assignment in certain cases (Pavel)
- Correct a previous fix for full coverage (Pavel)"
* tag 'io_uring-5.8-2020-07-12' of git://git.kernel.dk/linux-block:
io_uring: fix not initialised work->flags
io_uring: fix missing msg_name assignment
Use for_each_set_bit() instead of open-coding it to simplify the code.
Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Message-Id: <20200708062023.7986-1-vulab@iscas.ac.cn>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Pull btrfs fixes from David Sterba:
"Two refcounting fixes and one prepartory patch for upcoming splice
cleanup:
- fix double put of block group with nodatacow
- fix missing block group put when remounting with discard=async
- explicitly set splice callback (no functional change), to ease
integrating splice cleanup patches"
* tag 'for-5.8-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: wire up iter_file_splice_write
btrfs: fix double put of block group with nocow
btrfs: discard: add missing put when grabbing block group from unused list
59960b9deb535 ("io_uring: fix lazy work init") tried to fix missing
io_req_init_async(), but left out work.flags and hash. Do it earlier.
Fixes: 7cdaf587de7c ("io_uring: avoid whole io_wq_work copy for requests completed inline")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Increment *pos in the cpuinfo_op.next to fix the following warning
triggered by cat /proc/cpuinfo:
seq_file: buggy .next function c_next did not update position index
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Pull RISC-V fixes from Palmer Dabbelt:
"I have a few KGDB-related fixes. They're mostly fixes for build
warnings, but there's also:
- Support for the qSupported and qXfer packets, which are necessary
to pass around GDB XML information which we need for the RISC-V GDB
port to fully function.
- Users can now select STRICT_KERNEL_RWX instead of forcing it on"
* tag 'riscv-for-linus-5.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Avoid kgdb.h including gdb_xml.h to solve unused-const-variable warning
kgdb: Move the extern declaration kgdb_has_hit_break() to generic kgdb.h
riscv: Fix "no previous prototype" compile warning in kgdb.c file
riscv: enable the Kconfig prompt of STRICT_KERNEL_RWX
kgdb: enable arch to support XML packet.
btrfs implements the iter_write op and thus can use the more efficient
iov_iter based splice implementation. For now falling back to the less
efficient default is pretty harmless, but I have a pending series that
removes the default, and thus would cause btrfs to not support splice
at all.
Reported-by: Andy Lavr <andy.lavr@gmail.com>
Tested-by: Andy Lavr <andy.lavr@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Ensure to set msg.msg_name for the async portion of send/recvmsg,
as the header copy will copy to/from it.
Cc: stable@vger.kernel.org # v5.5+
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Building xtensa kernel with gcc-10 produces the following warnings:
arch/xtensa/kernel/xtensa_ksyms.c:90:15: warning: conflicting types
for built-in function ‘__sync_fetch_and_and_4’;
expected ‘unsigned int(volatile void *, unsigned int)’
[-Wbuiltin-declaration-mismatch]
arch/xtensa/kernel/xtensa_ksyms.c:96:15: warning: conflicting types
for built-in function ‘__sync_fetch_and_or_4’;
expected ‘unsigned int(volatile void *, unsigned int)’
[-Wbuiltin-declaration-mismatch]
Fix declarations of these functions to avoid the warning.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Pull SCSI fixes from James Bottomley:
"Five small fixes, four in driver and one in the SCSI Parallel
transport, which fixes an incredibly old bug so I suspect no-one has
actually used the functionality it fixes"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: dh: Add Fujitsu device to devinfo and dh lists
scsi: mpt3sas: Fix error returns in BRM_status_show
scsi: mpt3sas: Fix unlock imbalance
scsi: iscsi: Change iSCSI workqueue max_active back to 1
scsi: scsi_transport_spi: Fix function pointer check
The constant arrays in gdb_xml.h are only used in arch/riscv/kernel/kgdb.c,
but other c files may include the gdb_xml.h indirectly via including the
kgdb.h. Hence, It will cause many unused-const-variable warnings. This
patch makes the kgdb.h not to include the gdb_xml.h to solve this problem.
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
While debugging a patch that I wrote I was hitting use-after-free panics
when accessing block groups on unmount. This turned out to be because
in the nocow case if we bail out of doing the nocow for whatever reason
we need to call btrfs_dec_nocow_writers() if we called the inc. This
puts our block group, but a few error cases does
if (nocow) {
btrfs_dec_nocow_writers();
goto error;
}
unfortunately, error is
error:
if (nocow)
btrfs_dec_nocow_writers();
so we get a double put on our block group. Fix this by dropping the
error cases calling of btrfs_dec_nocow_writers(), as it's handled at the
error label now.
Fixes: 762bf09893b4 ("btrfs: improve error handling in run_delalloc_nocow")
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>