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
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Pull s390 cleanups from Vasily Gorbik:
"Update defconfigs and sort config select list"
* tag 's390-5.11-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/Kconfig: sort config S390 select list once again
s390: update defconfigs
Pull power management fixes from Rafael Wysocki:
"These fix a crash in intel_pstate during resume from suspend-to-RAM
that may occur after recent changes and two resource leaks in error
paths in the operating performance points (OPP) framework, add a new
C-states table to intel_idle and update the cpuidle MAINTAINERS entry
to cover the governors too.
Specifics:
- Fix recently introduced crash in the intel_pstate driver that
occurs if scale-invariance is disabled during resume from
suspend-to-RAM due to inconsistent changes of APERF or MPERF MSR
values made by the platform firmware (Rafael Wysocki).
- Fix a memory leak and add a missing clk_put() in error paths in the
OPP framework (Quanyang Wang, Viresh Kumar).
- Add new C-states table for SnowRidge processors to the intel_idle
driver (Artem Bityutskiy).
- Update the MAINTAINERS entry for cpuidle to make it clear that the
governors are covered by it too (Lukas Bulwahn)"
* tag 'pm-5.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
intel_idle: add SnowRidge C-state table
cpufreq: intel_pstate: Fix fast-switch fallback path
opp: Call the missing clk_put() on error
opp: fix memory leak in _allocate_opp_table
MAINTAINERS: include governors into CPU IDLE TIME MANAGEMENT FRAMEWORK
...and add comments at the top and bottom.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Pull SCSI fixes from James Bottomley:
"This is a load of driver fixes (12 ufs, 1 mpt3sas, 1 cxgbi).
The big core two fixes are for power management ("block: Do not accept
any requests while suspended" and "block: Fix a race in the runtime
power management code") which finally sorts out the resume problems
we've occasionally been having.
To make the resume fix, there are seven necessary precursors which
effectively renames REQ_PREEMPT to REQ_PM, so every "special" request
in block is automatically a power management exempt one.
All of the non-PM preempt cases are removed except for the one in the
SCSI Parallel Interface (spi) domain validation which is a genuine
case where we have to run requests at high priority to validate the
bus so this becomes an autopm get/put protected request"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (22 commits)
scsi: cxgb4i: Fix TLS dependency
scsi: ufs: Un-inline ufshcd_vops_device_reset function
scsi: ufs: Re-enable WriteBooster after device reset
scsi: ufs-mediatek: Use correct path to fix compile error
scsi: mpt3sas: Signedness bug in _base_get_diag_triggers()
scsi: block: Do not accept any requests while suspended
scsi: block: Remove RQF_PREEMPT and BLK_MQ_REQ_PREEMPT
scsi: core: Only process PM requests if rpm_status != RPM_ACTIVE
scsi: scsi_transport_spi: Set RQF_PM for domain validation commands
scsi: ide: Mark power management requests with RQF_PM instead of RQF_PREEMPT
scsi: ide: Do not set the RQF_PREEMPT flag for sense requests
scsi: block: Introduce BLK_MQ_REQ_PM
scsi: block: Fix a race in the runtime power management code
scsi: ufs-pci: Enable UFSHCD_CAP_RPM_AUTOSUSPEND for Intel controllers
scsi: ufs-pci: Fix recovery from hibernate exit errors for Intel controllers
scsi: ufs-pci: Ensure UFS device is in PowerDown mode for suspend-to-disk ->poweroff()
scsi: ufs-pci: Fix restore from S4 for Intel controllers
scsi: ufs-mediatek: Keep VCC always-on for specific devices
scsi: ufs: Allow regulators being always-on
scsi: ufs: Clear UAC for RPMB after ufshcd resets
...
* pm-cpufreq:
cpufreq: intel_pstate: Fix fast-switch fallback path
* pm-cpuidle:
intel_idle: add SnowRidge C-state table
MAINTAINERS: include governors into CPU IDLE TIME MANAGEMENT FRAMEWORK
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Pull block fixes from Jens Axboe:
"Two minor block fixes from this last week that should go into 5.11:
- Add missing NOWAIT debugfs definition (Andres)
- Fix kerneldoc warning introduced this merge window (Randy)"
* tag 'block-5.11-2021-01-01' of git://git.kernel.dk/linux-block:
block: add debugfs stanza for QUEUE_FLAG_NOWAIT
fs: block_dev.c: fix kernel-doc warnings from struct block_device changes
SCSI_CXGB4_ISCSI selects CHELSIO_T4. The latter depends on TLS || TLS=n, so
since 'select' does not check dependencies of the selected symbol,
SCSI_CXGB4_ISCSI should also depend on TLS || TLS=n.
This prevents the following kconfig warning and restricts SCSI_CXGB4_ISCSI
to 'm' whenever TLS=m.
WARNING: unmet direct dependencies detected for CHELSIO_T4
Depends on [m]: NETDEVICES [=y] && ETHERNET [=y] && NET_VENDOR_CHELSIO [=y] && PCI [=y] && (IPV6 [=y] || IPV6 [=y]=n) && (TLS [=m] || TLS [=m]=n)
Selected by [y]:
- SCSI_CXGB4_ISCSI [=y] && SCSI_LOWLEVEL [=y] && SCSI [=y] && PCI [=y] && INET [=y] && (IPV6 [=y] || IPV6 [=y]=n) && ETHERNET [=y]
Link: https://lore.kernel.org/r/20201208220505.24488-1-rdunlap@infradead.org
Fixes: 7b36b6e03b0d ("[SCSI] cxgb4i v5: iscsi driver")
Cc: Karen Xie <kxie@chelsio.com>
Cc: linux-scsi@vger.kernel.org
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Pull operating performance points (OPP) framework fixes for 5.11-rc2
from Viresh Kumar:
"This contains two patches to fix freeing of resources in error paths."
* 'opp/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm:
opp: Call the missing clk_put() on error
opp: fix memory leak in _allocate_opp_table
When sugov_update_single_perf() falls back to the "frequency"
path due to the missing scale-invariance, it will call
cpufreq_driver_fast_switch() via sugov_fast_switch()
and the driver's ->fast_switch() callback will be invoked,
so it must not be NULL.
However, after commit a365ab6b9dfb ("cpufreq: intel_pstate: Implement
the ->adjust_perf() callback") intel_pstate sets ->fast_switch() to
NULL when it is going to use intel_cpufreq_adjust_perf(), which is a
mistake, because on x86 the scale-invariance may be turned off
dynamically, so modify it to retain the original ->adjust_perf()
callback pointer.
Fixes: a365ab6b9dfb ("cpufreq: intel_pstate: Implement the ->adjust_perf() callback")
Reported-by: Kenneth R. Crudup <kenny@panix.com>
Tested-by: Kenneth R. Crudup <kenny@panix.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add C-state table for the SnowRidge SoC which is found on Intel Jacobsville
platforms.
The following has been changed.
1. C1E latency changed from 10us to 15us. It was measured using the
open source "wult" tool (the "nic" method, 15us is the 99.99th
percentile).
2. C1E power break even changed from 20us to 25us, which may result
in less C1E residency in some workloads.
3. C6 latency changed from 50us to 130us. Measured the same way as C1E.
The C6 C-state is supported only by some SnowRidge revisions, so add a C-state
table commentary about this.
On SnowRidge, C6 support is enumerated via the usual mechanism: "mwait" leaf of
the "cpuid" instruction. The 'intel_idle' driver does check this leaf, so even
though C6 is present in the table, the driver will only use it if the CPU does
support it.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull io_uring fixes from Jens Axboe:
"A few fixes that should go into 5.11, all marked for stable as well:
- Fix issue around identity COW'ing and users that share a ring
across processes
- Fix a hang associated with unregistering fixed files (Pavel)
- Move the 'process is exiting' cancelation a bit earlier, so
task_works aren't affected by it (Pavel)"
* tag 'io_uring-5.11-2021-01-01' of git://git.kernel.dk/linux-block:
kernel/io_uring: cancel io_uring before task works
io_uring: fix io_sqe_files_unregister() hangs
io_uring: add a helper for setting a ref node
io_uring: don't assume mm is constant across submits