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
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Since commit 36e2c7421f02 ("fs: don't allow splice read/write without
explicit ops") we've required that file operation structures explicitly
enable splice support, rather than falling back to the default handlers.
Most /proc files use the indirect 'struct proc_ops' to describe their
file operations, and were fixed up to support splice earlier in commits
40be821d627c..b24c30c67863, but the mountinfo files interact with the
VFS directly using their own 'struct file_operations' and got missed as
a result.
This adds the necessary support for splice to work for /proc/*/mountinfo
and friends.
Reported-by: Joan Bruguera Micó <joanbrugueram@gmail.com>
Reported-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=209971
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull NTB fixes from Jon Mason:
"Bug fix for IDT NTB and Intel NTB LTR management support"
* tag 'ntb-5.11' of git://github.com/jonmason/ntb:
ntb: intel: add Intel NTB LTR vendor support for gen4 NTB
ntb: idt: fix error check in ntb_hw_idt.c
Pull crypto fixes from Herbert Xu:
"Fix a number of autobuild failures due to missing Kconfig
dependencies"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: qat - add CRYPTO_AES to Kconfig dependencies
crypto: keembay - Add dependency on HAS_IOMEM
crypto: keembay - CRYPTO_DEV_KEEMBAY_OCS_AES_SM4 should depend on ARCH_KEEMBAY
Intel NTB device has custom LTR management that is not compliant with the
PCIe standard. Add support to set LTR status triggered by link status
change.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
Pull objtool fix from Ingo Molnar:
"Fix a segfault that occurs when built with Clang"
* tag 'objtool-urgent-2020-12-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Fix seg fault with Clang non-section symbols
This patch includes a missing dependency (CRYPTO_AES) which may
lead to an "undefined reference to `aes_expandkey'" linking error.
Fixes: 5106dfeaeabe ("crypto: qat - add AES-XTS support for QAT GEN4 devices")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Marco Chiappero <marco.chiappero@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
idt_create_dev never return NULL and fix smatch warning.
Signed-off-by: Wang Qing <wangqing@vivo.com>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
Pull locking fixes from Ingo Molnar:
"Misc fixes/updates:
- Fix static keys usage in module __init sections
- Add separate MAINTAINERS entry for static branches/calls
- Fix lockdep splat with CONFIG_PREEMPTIRQ_EVENTS=y tracing"
* tag 'locking-urgent-2020-12-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
softirq: Avoid bad tracing / lockdep interaction
jump_label/static_call: Add MAINTAINERS
jump_label: Fix usage in module __init
The Clang assembler likes to strip section symbols, which means objtool
can't reference some text code by its section. This confuses objtool
greatly, causing it to seg fault.
The fix is similar to what was done before, for ORC reloc generation:
e81e07244325 ("objtool: Support Clang non-section symbols in ORC generation")
Factor out that code into a common helper and use it for static call
reloc generation as well.
Reported-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://github.com/ClangBuiltLinux/linux/issues/1207
Link: https://lkml.kernel.org/r/ba6b6c0f0dd5acbba66e403955a967d9fdd1726a.1607983452.git.jpoimboe@redhat.com
Add dependency for CRYPTO_DEV_KEEMBAY_OCS_AES_SM4 on HAS_IOMEM to
prevent build failures.
Fixes: 88574332451380f4 ("crypto: keembay - Add support for Keem Bay OCS AES/SM4")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Daniele Alessandrelli <daniele.alessandrelli@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull timer fixes from Ingo Molnar:
"Update/fix two CPU sanity checks in the hotplug and the boot code, and
fix a typo in the Kconfig help text.
[ Context: the first two commits are the result of an ongoing
annotation+review work of (intentional) tick_do_timer_cpu() data
races reported by KCSAN, but the annotations aren't fully cooked
yet ]"
* tag 'timers-urgent-2020-12-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timekeeping: Fix spelling mistake in Kconfig "fullfill" -> "fulfill"
tick/sched: Remove bogus boot "safety" check
tick: Remove pointless cpu valid check in hotplug code
Similar to commit:
1a63dcd8765b ("softirq: Reorder trace_softirqs_on to prevent lockdep splat")
__local_bh_enable_ip() can also call into tracing with inconsistent
state. Unlike that commit we don't need to bother about the tracepoint
because 'cnt-1' never matches preempt_count() (by construction).
Reported-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://lkml.kernel.org/r/20201218154519.GW3092@hirez.programming.kicks-ass.net