Linux kernel
============
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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
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Pull libnvdimm fixes from Dan Williams:
"A fix for a crash scenario that has been present since the initial
merge, a minor regression in sysfs attribute visibility, and a fix for
some flexible array warnings.
The bulk of this pull is an update to the libnvdimm unit test
infrastructure to test non-ACPI platforms. Given there is zero
regression risk for test updates, and the tests enable validation of
bits headed towards the next merge window, I saw no reason to hold the
new tests back. Santosh originally submitted this before the v5.11
window opened.
Summary:
- Fix a crash when sysfs accesses race 'dimm' driver probe/remove.
- Fix a regression in 'resource' attribute visibility necessary for
mapping badblocks and other physical address interrogations.
- Fix some flexible array warnings
- Expand the unit test infrastructure for non-ACPI platforms"
* tag 'libnvdimm-fixes-5.11-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
libnvdimm/dimm: Avoid race between probe and available_slots_show()
ndtest: Add papr health related flags
ndtest: Add nvdimm control functions
ndtest: Add regions and mappings to the test buses
ndtest: Add dimm attributes
ndtest: Add dimms to the two buses
ndtest: Add compatability string to treat it as PAPR family
testing/nvdimm: Add test module for non-nfit platforms
libnvdimm/namespace: Fix visibility of namespace resource attribute
libnvdimm/pmem: Remove unused header
ACPI: NFIT: Fix flexible_array.cocci warnings
Pull dma-mapping fix from Christoph Hellwig:
"Fix a 32 vs 64-bit padding issue in the new benchmark code (Barry
Song)"
* tag 'dma-mapping-5.11-2' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: benchmark: use u8 for reserved field in uAPI structure
Richard reports that the following test:
(while true; do
cat /sys/bus/nd/devices/nmem*/available_slots 2>&1 > /dev/null
done) &
while true; do
for i in $(seq 0 4); do
echo nmem$i > /sys/bus/nd/drivers/nvdimm/bind
done
for i in $(seq 0 4); do
echo nmem$i > /sys/bus/nd/drivers/nvdimm/unbind
done
done
...fails with a crash signature like:
divide error: 0000 [#1] SMP KASAN PTI
RIP: 0010:nd_label_nfree+0x134/0x1a0 [libnvdimm]
[..]
Call Trace:
available_slots_show+0x4e/0x120 [libnvdimm]
dev_attr_show+0x42/0x80
? memset+0x20/0x40
sysfs_kf_seq_show+0x218/0x410
The root cause is that available_slots_show() consults driver-data, but
fails to synchronize against device-unbind setting up a TOCTOU race to
access uninitialized memory.
Validate driver-data under the device-lock.
Fixes: 4d88a97aa9e8 ("libnvdimm, nvdimm: dimm driver and base libnvdimm device-driver infrastructure")
Cc: <stable@vger.kernel.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Coly Li <colyli@suse.com>
Reported-by: Richard Palethorpe <rpalethorpe@suse.com>
Acked-by: Richard Palethorpe <rpalethorpe@suse.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull irq fixes from Borislav Petkov:
- Prevent device managed IRQ allocation helpers from returning IRQ 0
- A fix for MSI activation of PCI endpoints with multiple MSIs
* tag 'irq_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Prevent [devm_]irq_alloc_desc from returning irq 0
genirq/msi: Activate Multi-MSI early when MSI_FLAG_ACTIVATE_EARLY is set
The original code put five u32 before a u64 expansion[10] array. Five is
odd, this will cause trouble in the extension of the structure by adding
new features. This patch moves to use u8 for reserved field to avoid
future alignment risk.
Meanwhile, it also clears the memory of struct map_benchmark in tools,
otherwise, if users use old version to run on newer kernel, the random
expansion value will cause side effect on newer kernel.
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
sysfs attibutes to show health related flags are added.
Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Link: https://lore.kernel.org/r/20201222042240.2983755-8-santosh@fossix.org
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull syscall entry fixes from Borislav Petkov:
- For syscall user dispatch, separate prctl operation from syscall
redirection range specification before the API has been made official
in 5.11.
- Ensure tasks using the generic syscall code do trap after returning
from a syscall when single-stepping is requested.
* tag 'core_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
entry: Use different define for selector variable in SUD
entry: Ensure trap after single-step on system call return
Since commit a85a6c86c25b ("driver core: platform: Clarify that IRQ 0
is invalid"), having a linux-irq with number 0 will trigger a WARN()
when calling platform_get_irq*() to retrieve that linux-irq.
Since [devm_]irq_alloc_desc allocs a single irq and since irq 0 is not used
on some systems, it can return 0, triggering that WARN(). This happens
e.g. on Intel Bay Trail and Cherry Trail devices using the LPE audio engine
for HDMI audio:
0 is an invalid IRQ number
WARNING: CPU: 3 PID: 472 at drivers/base/platform.c:238 platform_get_irq_optional+0x108/0x180
Modules linked in: snd_hdmi_lpe_audio(+) ...
Call Trace:
platform_get_irq+0x17/0x30
hdmi_lpe_audio_probe+0x4a/0x6c0 [snd_hdmi_lpe_audio]
---[ end trace ceece38854223a0b ]---
Change the 'from' parameter passed to __[devm_]irq_alloc_descs() by the
[devm_]irq_alloc_desc macros from 0 to 1, so that these macros will no
longer return 0.
Fixes: a85a6c86c25b ("driver core: platform: Clarify that IRQ 0 is invalid")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201221185647.226146-1-hdegoede@redhat.com
Pull PCI fix from Bjorn Helgaas:
"Revert ASPM suspend/resume fix that regressed NVMe devices (Bjorn
Helgaas)"
* tag 'pci-v5.11-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
Revert "PCI/ASPM: Save/restore L1SS Capability for suspend/resume"
Add functions to support ND_CMD_GET_CONFIG_SIZE, ND_CMD_SET_CONFIG_DATA and
ND_CMD_GET_CONFIG_DATA.
Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Link: https://lore.kernel.org/r/20201222042240.2983755-7-santosh@fossix.org
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull scheduler fix from Borislav Petkov:
"Revert an attempt to not spread IRQ threads on isolated CPUs which has
a bunch of problems"
* tag 'sched_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "lib: Restrict cpumask_local_spread to houskeeping CPUs"
Michael Kerrisk suggested that, from an API perspective, it is a bad
idea to share the PR_SYS_DISPATCH_ defines between the prctl operation
and the selector variable.
Therefore, define two new constants to be used by SUD's selector variable
and update the corresponding documentation and test cases.
While this changes the API syscall user dispatch has never been part of a
Linux release, it will show up for the first time in 5.11.
Suggested-by: Michael Kerrisk (man-pages) <mtk.manpages@gmail.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210205184321.2062251-1-krisman@collabora.com
When MSI_FLAG_ACTIVATE_EARLY is set (which is the case for PCI),
__msi_domain_alloc_irqs() performs the activation of the interrupt (which
in the case of PCI results in the endpoint being programmed) as soon as the
interrupt is allocated.
But it appears that this is only done for the first vector, introducing an
inconsistent behaviour for PCI Multi-MSI.
Fix it by iterating over the number of vectors allocated to each MSI
descriptor. This is easily achieved by introducing a new
"for_each_msi_vector" iterator, together with a tiny bit of refactoring.
Fixes: f3b0946d629c ("genirq/msi: Make sure PCI MSIs are activated early")
Reported-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210123122759.1781359-1-maz@kernel.org