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Linux kernel
============
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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.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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seqcount_init() must be a macro in order to preserve the static
variable that is used for the lockdep key. Don't then wrap it in an
inline function, which destroys that.
Luckily there aren't many users of this function, but fix it before it
becomes a problem.
Fixes: 80793c3471d9 ("seqlock: Introduce seqcount_latch_t")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/YEeFEbNUVkZaXDp4@hirez.programming.kicks-ass.net
Jakub reported that:
static struct net_device *rtl8139_init_board(struct pci_dev *pdev)
{
...
u64_stats_init(&tp->rx_stats.syncp);
u64_stats_init(&tp->tx_stats.syncp);
...
}
results in lockdep getting confused between the RX and TX stats lock.
This is because u64_stats_init() is an inline calling seqcount_init(),
which is a macro using a static variable to generate a lockdep class.
By wrapping that in an inline, we negate the effect of the macro and
fold the static key variable, hence the confusion.
Fix by also making u64_stats_init() a macro for the case where it
matters, leaving the other case an inline for argument validation
etc.
Reported-by: Jakub Kicinski <kuba@kernel.org>
Debugged-by: "Ahmed S. Darwish" <a.darwish@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: "Erhard F." <erhard_f@mailbox.org>
Link: https://lkml.kernel.org/r/YEXicy6+9MksdLZh@hirez.programming.kicks-ass.net
Provided the target address of a R_X86_64_PC32 relocation is aligned,
the low two bits should be invariant between the relative and absolute
value.
Turns out the address is not aligned and things go sideways, ensure we
transfer the bits in the absolute form when fixing up the key address.
Fixes: 73f44fe19d35 ("static_call: Allow module use without exposing static_call_key")
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20210225220351.GE4746@worktop.programming.kicks-ass.net
Pull rdma fixes from Jason Gunthorpe:
"Nothing special here, though Bob's regression fixes for rxe would have
made it before the rc cycle had there not been such strong winter
weather!
- Fix corner cases in the rxe reference counting cleanup that are
causing regressions in blktests for SRP
- Two kdoc fixes so W=1 is clean
- Missing error return in error unwind for mlx5
- Wrong lock type nesting in IB CM"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
RDMA/rxe: Fix errant WARN_ONCE in rxe_completer()
RDMA/rxe: Fix extra deref in rxe_rcv_mcast_pkt()
RDMA/rxe: Fix missed IB reference counting in loopback
RDMA/uverbs: Fix kernel-doc warning of _uverbs_alloc
RDMA/mlx5: Set correct kernel-doc identifier
IB/mlx5: Add missing error code
RDMA/rxe: Fix missing kconfig dependency on CRYPTO
RDMA/cm: Fix IRQ restore in ib_send_cm_sidr_rep
Pull gcc-plugins fixes from Kees Cook:
"Tiny gcc-plugin fixes for v5.12-rc2. These issues are small but have
been reported a couple times now by static analyzers, so best to get
them fixed to reduce the noise. :)
- Fix coding style issues (Jason Yan)"
* tag 'gcc-plugins-v5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
gcc-plugins: latent_entropy: remove unneeded semicolon
gcc-plugins: structleak: remove unneeded variable 'ret'
In rxe_comp.c in rxe_completer() the function free_pkt() did not clear skb
which triggered a warning at 'done:' and could possibly at 'exit:'. The
WARN_ONCE() calls are not actually needed. The call to free_pkt() is
moved to the end to clearly show that all skbs are freed.
Fixes: 899aba891cab ("RDMA/rxe: Fix FIXME in rxe_udp_encap_recv()")
Link: https://lore.kernel.org/r/20210304192048.2958-1-rpearson@hpe.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Pull pstore fixes from Kees Cook:
- Rate-limit ECC warnings (Dmitry Osipenko)
- Fix error path check for NULL (Tetsuo Handa)
* tag 'pstore-v5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
pstore/ram: Rate-limit "uncorrectable error in header" message
pstore: Fix warning in pstore_kill_sb()
Fix the following coccicheck warning:
scripts/gcc-plugins/latent_entropy_plugin.c:539:2-3: Unneeded semicolon
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200418070521.10931-1-yanaijie@huawei.com
rxe_rcv_mcast_pkt() dropped a reference to ib_device when no error
occurred causing an underflow on the reference counter. This code is
cleaned up to be clearer and easier to read.
Fixes: 899aba891cab ("RDMA/rxe: Fix FIXME in rxe_udp_encap_recv()")
Link: https://lore.kernel.org/r/20210304192048.2958-1-rpearson@hpe.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Pull device mapper fixes from Mike Snitzer:
"Fix DM verity target's optional Forward Error Correction (FEC) for
Reed-Solomon roots that are unaligned to block size"
* tag 'for-5.12/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm verity: fix FEC for RS roots unaligned to block size
dm bufio: subtract the number of initial sectors in dm_bufio_get_device_size
There is a quite huge "uncorrectable error in header" flood in KMSG
on a clean system boot since there is no pstore buffer saved in RAM.
Let's silence the redundant noisy messages by rate-limiting the printk
message. Now there are maximum 10 messages printed repeatedly instead
of 35+.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210302095850.30894-1-digetx@gmail.com
Fix the following coccicheck warning:
scripts/gcc-plugins/structleak_plugin.c:177:14-17: Unneeded variable:
"ret". Return "0" on line 207
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200418070505.10715-1-yanaijie@huawei.com
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