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2021-09-18docs: Fix infiniband uverbs minor numberLeon Romanovsky1-3/+3
[ Upstream commit 8d7e415d55610d503fdb8815344846b72d194a40 ] Starting from the beginning of infiniband subsystem, the uverbs char devices start from 192 as a minor number, see commit bc38a6abdd5a ("[PATCH] IB uverbs: core implementation"). This patch updates the admin guide documentation to reflect it. Fixes: 9d85025b0418 ("docs-rst: create an user's manual book") Link: https://lore.kernel.org/r/bad03e6bcde45550c01e12908a6fe7dfa4770703.1627477347.git.leonro@nvidia.com Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14clocksource: Retry clock read if long delays detectedPaul E. McKenney1-0/+6
[ Upstream commit db3a34e17433de2390eb80d436970edcebd0ca3e ] When the clocksource watchdog marks a clock as unstable, this might be due to that clock being unstable or it might be due to delays that happen to occur between the reads of the two clocks. Yes, interrupts are disabled across those two reads, but there are no shortage of things that can delay interrupts-disabled regions of code ranging from SMI handlers to vCPU preemption. It would be good to have some indication as to why the clock was marked unstable. Therefore, re-read the watchdog clock on either side of the read from the clock under test. If the watchdog clock shows an excessive time delta between its pair of reads, the reads are retried. The maximum number of retries is specified by a new kernel boot parameter clocksource.max_cswd_read_retries, which defaults to three, that is, up to four reads, one initial and up to three retries. If more than one retry was required, a message is printed on the console (the occasional single retry is expected behavior, especially in guest OSes). If the maximum number of retries is exceeded, the clock under test will be marked unstable. However, the probability of this happening due to various sorts of delays is quite small. In addition, the reason (clock-read delays) for the unstable marking will be apparent. Reported-by: Chris Mason <clm@fb.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Feng Tang <feng.tang@intel.com> Link: https://lore.kernel.org/r/20210527190124.440372-1-paulmck@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-17drivers/base/memory: don't store phys_device in memory blocksDavid Hildenbrand1-2/+2
[ Upstream commit e9a2e48e8704c9d20a625c6f2357147d03ea7b97 ] No need to store the value for each and every memory block, as we can easily query the value at runtime. Reshuffle the members to optimize the memory layout. Also, let's clarify what the interface once was used for and why it's legacy nowadays. "phys_device" was used on s390x in older versions of lsmem[2]/chmem[3], back when they were still part of s390x-tools. They were later replaced by the variants in linux-utils. For example, RHEL6 and RHEL7 contain lsmem/chmem from s390-utils. RHEL8 switched to versions from util-linux on s390x [4]. "phys_device" was added with sysfs support for memory hotplug in commit 3947be1969a9 ("[PATCH] memory hotplug: sysfs and add/remove functions") in 2005. It always returned 0. s390x started returning something != 0 on some setups (if sclp.rzm is set by HW) in 2010 via commit 57b552ba0b2f ("memory hotplug/s390: set phys_device"). For s390x, it allowed for identifying which memory block devices belong to the same storage increment (RZM). Only if all memory block devices comprising a single storage increment were offline, the memory could actually be removed in the hypervisor. Since commit e5d709bb5fb7 ("s390/memory hotplug: provide memory_block_size_bytes() function") in 2013 a memory block device spans at least one storage increment - which is why the interface isn't really helpful/used anymore (except by old lsmem/chmem tools). There were once RFC patches to make use of "phys_device" in ACPI context; however, the underlying problem could be solved using different interfaces [1]. [1] https://patchwork.kernel.org/patch/2163871/ [2] https://github.com/ibm-s390-tools/s390-tools/blob/v2.1.0/zconf/lsmem [3] https://github.com/ibm-s390-tools/s390-tools/blob/v2.1.0/zconf/chmem [4] https://bugzilla.redhat.com/show_bug.cgi?id=1504134 Link: https://lkml.kernel.org/r/20210201181347.13262-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Cc: Ilya Dryomov <idryomov@gmail.com> Cc: Vaibhav Jain <vaibhav@linux.ibm.com> Cc: Tom Rix <trix@redhat.com> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-04mm/vmscan: restore zone_reclaim_mode ABIDave Hansen1-5/+5
commit 519983645a9f2ec339cabfa0c6ef7b09be985dd0 upstream. I went to go add a new RECLAIM_* mode for the zone_reclaim_mode sysctl. Like a good kernel developer, I also went to go update the documentation. I noticed that the bits in the documentation didn't match the bits in the #defines. The VM never explicitly checks the RECLAIM_ZONE bit. The bit is, however implicitly checked when checking 'node_reclaim_mode==0'. The RECLAIM_ZONE #define was removed in a cleanup. That, by itself is fine. But, when the bit was removed (bit 0) the _other_ bit locations also got changed. That's not OK because the bit values are documented to mean one specific thing. Users surely do not expect the meaning to change from kernel to kernel. The end result is that if someone had a script that did: sysctl vm.zone_reclaim_mode=1 it would have gone from enabling node reclaim for clean unmapped pages to writing out pages during node reclaim after the commit in question. That's not great. Put the bits back the way they were and add a comment so something like this is a bit harder to do again. Update the documentation to make it clear that the first bit is ignored. Link: https://lkml.kernel.org/r/20210219172555.FF0CDF23@viggo.jf.intel.com Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Fixes: 648b5cf368e0 ("mm/vmscan: remove unused RECLAIM_OFF/RECLAIM_ZONE") Reviewed-by: Ben Widawsky <ben.widawsky@intel.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Alex Shi <alex.shi@linux.alibaba.com> Cc: Daniel Wagner <dwagner@suse.de> Cc: "Tobin C. Harding" <tobin@kernel.org> Cc: Christoph Lameter <cl@linux.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Qian Cai <cai@lca.pw> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04perf/arm-cmn: Fix PMU instance namingRobin Murphy1-1/+1
[ Upstream commit 79d7c3dca99fa96033695ddf5d495b775a3a137b ] Although it's neat to avoid the suffix for the typical case of a single PMU, it means systems with multiple CMN instances end up with inconsistent naming. I think it also breaks perf tool's "uncore alias" logic if the common instance prefix is also the full name of one. Avoid any surprises by not trying to be clever and simply numbering every instance, even when it might technically prove redundant. Fixes: 0ba64770a2f2 ("perf: Add Arm CMN-600 PMU driver") Signed-off-by: Robin Murphy <robin.murphy@arm.com> Link: https://lore.kernel.org/r/649a2281233f193d59240b13ed91b57337c77b32.1611839564.git.robin.murphy@arm.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-27x86/xen: Add xen_no_vector_callback option to test PCI INTX deliveryDavid Woodhouse1-0/+4
[ Upstream commit b36b0fe96af13460278bf9b173beced1bd15f85d ] It's useful to be able to test non-vector event channel delivery, to make sure Linux will work properly on older Xen which doesn't have it. It's also useful for those working on Xen and Xen-compatible hypervisors, because there are guest kernels still in active use which use PCI INTX even when vector delivery is available. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20210106153958.584169-4-dwmw2@infradead.org Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-27dm integrity: conditionally disable "recalculate" featureMikulas Patocka1-3/+9
commit 5c02406428d5219c367c5f53457698c58bc5f917 upstream. Otherwise a malicious user could (ab)use the "recalculate" feature that makes dm-integrity calculate the checksums in the background while the device is already usable. When the system restarts before all checksums have been calculated, the calculation continues where it was interrupted even if the recalculate feature is not requested the next time the dm device is set up. Disable recalculating if we use internal_hash or journal_hash with a key (e.g. HMAC) and we don't have the "legacy_recalculate" flag. This may break activation of a volume, created by an older kernel, that is not yet fully recalculated -- if this happens, the user should add the "legacy_recalculate" flag to constructor parameters. Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reported-by: Daniel Glockner <dg@emlix.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-21USB: UAS: introduce a quirk to set no_write_sameOliver Neukum1-0/+1
commit 8010622c86ca5bb44bc98492f5968726fc7c7a21 upstream. UAS does not share the pessimistic assumption storage is making that devices cannot deal with WRITE_SAME. A few devices supported by UAS, are reported to not deal well with WRITE_SAME. Those need a quirk. Add it to the device that needs it. Reported-by: David C. Partridge <david.partridge@perdrix.co.uk> Signed-off-by: Oliver Neukum <oneukum@suse.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20201209152639.9195-1-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-02Merge tag 'trace-v5.10-rc6-bootconfig' of ↵Linus Torvalds1-1/+3
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull bootconfig fixes from Steven Rostedt: "Have bootconfig size and checksum be little endian In case the bootconfig is created on one kind of endian machine, and then read on the other kind of endian kernel, the size and checksum will be incorrect. Instead, have both the size and checksum always be little endian and have the tool and the kernel convert it from little endian to or from the host endian" * tag 'trace-v5.10-rc6-bootconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: docs: bootconfig: Add the endianness of fields tools/bootconfig: Store size and checksum in footer as le32 bootconfig: Load size and checksum in the footer as le32
2020-12-01Merge tag 'trace-v5.10-rc6' of ↵Linus Torvalds1-5/+13
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: - Use correct timestamp variable for ring buffer write stamp update - Fix up before stamp and write stamp when crossing ring buffer sub buffers - Keep a zero delta in ring buffer in slow path if cmpxchg fails - Fix trace_printk static buffer for archs that care - Fix ftrace record accounting for ftrace ops with trampolines - Fix DYNAMIC_FTRACE_WITH_DIRECT_CALLS dependency - Remove WARN_ON in hwlat tracer that triggers on something that is OK - Make "my_tramp" trampoline in ftrace direct sample code global - Fixes in the bootconfig tool for better alignment management * tag 'trace-v5.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ring-buffer: Always check to put back before stamp when crossing pages ftrace: Fix DYNAMIC_FTRACE_WITH_DIRECT_CALLS dependency ftrace: Fix updating FTRACE_FL_TRAMP tracing: Fix alignment of static buffer tracing: Remove WARN_ON in start_thread() samples/ftrace: Mark my_tramp[12]? global ring-buffer: Set the right timestamp in the slow path of __rb_reserve_next() ring-buffer: Update write stamp with the correct ts docs: bootconfig: Update file format on initrd image tools/bootconfig: Align the bootconfig applied initrd image size to 4 tools/bootconfig: Fix to check the write failure correctly tools/bootconfig: Fix errno reference after printf()
2020-11-30docs: bootconfig: Add the endianness of fieldsMasami Hiramatsu1-1/+3
Add a description about the endianness of the size and the checksum fields. Those must be stored as le32 instead of u32. This will allow us to apply bootconfig to the cross build initrd without caring the endianness. Link: https://lkml.kernel.org/r/160583936246.547349.10964204130590955409.stgit@devnote2 Reported-by: Steven Rostedt <rostedt@goodmis.org> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-11-19Merge tag 'powerpc-cve-2020-4788' of ↵Linus Torvalds1-0/+7
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: "Fixes for CVE-2020-4788. From Daniel's cover letter: IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch series flushes the L1 cache on kernel entry (patch 2) and after the kernel performs any user accesses (patch 3). It also adds a self-test and performs some related cleanups" * tag 'powerpc-cve-2020-4788' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/64s: rename pnv|pseries_setup_rfi_flush to _setup_security_mitigations selftests/powerpc: refactor entry and rfi_flush tests selftests/powerpc: entry flush test powerpc: Only include kup-radix.h for 64-bit Book3S powerpc/64s: flush L1D after user accesses powerpc/64s: flush L1D on kernel entry selftests/powerpc: rfi_flush: disable entry flush if present
2020-11-19docs: bootconfig: Update file format on initrd imageMasami Hiramatsu1-5/+13
To align the total file size, add padding null character when appending the bootconfig to initrd image. Link: https://lkml.kernel.org/r/160576522916.320071.4145530996151028855.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-11-19powerpc/64s: flush L1D after user accessesNicholas Piggin1-0/+4
IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache after user accesses. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2020-11-19powerpc/64s: flush L1D on kernel entryNicholas Piggin1-0/+3
IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache on kernel entry. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2020-11-05Merge tag 'pm-5.10-rc3' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fixes from Rafael Wysocki: "These fix the device links support in runtime PM, correct mistakes in the cpuidle documentation, fix the handling of policy limits changes in the schedutil cpufreq governor, fix assorted issues in the OPP (operating performance points) framework and make one janitorial change. Specifics: - Unify the handling of managed and stateless device links in the runtime PM framework and prevent runtime PM references to devices from being leaked after device link removal (Rafael Wysocki). - Fix two mistakes in the cpuidle documentation (Julia Lawall). - Prevent the schedutil cpufreq governor from missing policy limits updates in some cases (Viresh Kumar). - Prevent static OPPs from being dropped by mistake (Viresh Kumar). - Prevent helper function in the OPP framework from returning prematurely (Viresh Kumar). - Prevent opp_table_lock from being held too long during removal of OPP tables with no more active references (Viresh Kumar). - Drop redundant semicolon from the Intel RAPL power capping driver (Tom Rix)" * tag 'pm-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM: runtime: Resume the device earlier in __device_release_driver() PM: runtime: Drop pm_runtime_clean_up_links() PM: runtime: Drop runtime PM references to supplier on link removal powercap/intel_rapl: remove unneeded semicolon Documentation: PM: cpuidle: correct path name Documentation: PM: cpuidle: correct typo cpufreq: schedutil: Don't skip freq update if need_freq_update is set opp: Reduce the size of critical section in _opp_table_kref_release() opp: Fix early exit from dev_pm_opp_register_set_opp_helper() opp: Don't always remove static OPPs in _of_add_opp_table_v1()
2020-11-03Merge tag 'docs-5.10-warnings' of git://git.lwn.net/linuxLinus Torvalds2-1/+2
Pull documentation build warning fixes from Jonathan Corbet: "This contains a series of warning fixes from Mauro; once applied, the number of warnings from the once-noisy docs build process is nearly zero. Getting to this point has required a lot of work; once there, hopefully we can keep things that way. I have packaged this as a separate pull because it does a fair amount of reaching outside of Documentation/. The changes are all in comments and in code placement. It's all been in linux-next since last week" * tag 'docs-5.10-warnings' of git://git.lwn.net/linux: (24 commits) docs: SafeSetID: fix a warning amdgpu: fix a few kernel-doc markup issues selftests: kselftest_harness.h: fix kernel-doc markups drm: amdgpu_dm: fix a typo gpu: docs: amdgpu.rst: get rid of wrong kernel-doc markups drm: amdgpu: kernel-doc: update some adev parameters docs: fs: api-summary.rst: get rid of kernel-doc include IB/srpt: docs: add a description for cq_size member locking/refcount: move kernel-doc markups to the proper place docs: lockdep-design: fix some warning issues MAINTAINERS: fix broken doc refs due to yaml conversion ice: docs fix a devlink info that broke a table crypto: sun8x-ce*: update entries to its documentation net: phy: remove kernel-doc duplication mm: pagemap.h: fix two kernel-doc markups blk-mq: docs: add kernel-doc description for a new struct member docs: userspace-api: add iommu.rst to the index file docs: hwmon: mp2975.rst: address some html build warnings docs: net: statistics.rst: remove a duplicated kernel-doc docs: kasan.rst: add two missing blank lines ...
2020-11-02Documentation: PM: cpuidle: correct path nameJulia Lawall1-1/+1
cpu/ is needed before cpu<N>/ Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-02Documentation: PM: cpuidle: correct typoJulia Lawall1-1/+1
cerainly -> certainly Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-30docs: abi-testing.rst: enable --rst-sources when building docsMauro Carvalho Chehab1-0/+1
Now that ABI/testing documents were fixed, add --rst-sources to the ABI/testing too. Acked-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/9242473fd3df785565bb6084b1b814cc15074fb2.1604042072.git.mchehab+huawei@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-30docs: ABI: don't escape ReST-incompatible chars from obsolete and removedMauro Carvalho Chehab2-0/+2
With just a single fix, the contents there can be parsed properly without the need to escape any ReST incompatible stuff. Acked-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/472f4574b6aa2ff4de5a819db1a4a5c9a34f5168.1604042072.git.mchehab+huawei@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-30docs: ABI: create a 2-depth index for ABIMauro Carvalho Chehab1-1/+1
That helps to identify what ABI files are adding titles. Acked-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/e267b36ae7f32bab2a86f1da6b40bb3e62c877d4.1604042072.git.mchehab+huawei@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-30docs: ABI: make it parse ABI/stable as ReST-compatible filesMauro Carvalho Chehab1-0/+1
Now that the stable ABI files are compatible with ReST, parse them without converting complex descriptions as literal blocks nor escaping special characters. Please notice that escaping special characters will probably be needed at descriptions, at least for the asterisk character. Acked-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/59ccbaa75ff05f23e701dd9a0bbe118e9343a553.1604042072.git.mchehab+huawei@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-30docs: add ABI documentation to the admin-guide bookMauro Carvalho Chehab6-0/+59
As we don't want a generic Sphinx extension to execute commands, change the one proposed to Markus to call the abi_book.pl script. Use a script to parse the Documentation/ABI directory and output it at the admin-guide. Acked-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/5651482b06500e69a1acdf92152f90a203e6521d.1604042072.git.mchehab+huawei@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-28docs: SafeSetID: fix a warningMauro Carvalho Chehab1-1/+1
As reported by Sphinx 2.4.4: docs/Documentation/admin-guide/LSM/SafeSetID.rst:110: WARNING: Title underline too short. Note on GID policies and setgroups() ================== Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/4afa281c170daabd1ce522653d5d5d5078ebd92c.1603791716.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-10-28docs: admin-guide: net.rst: add a missing blank lineMauro Carvalho Chehab1-0/+1
There's a missing blank line after a literal block, which causes this warning: Documentation/admin-guide/sysctl/net.rst:303: WARNING: Literal block ends without a blank line; unexpected unindent. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/b2545be4a4c71269d10278b5990c3e06c4b65f84.1603791716.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-10-25Merge tag 'for-linus-5.10b-rc1c-tag' of ↵Linus Torvalds1-0/+7
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull more xen updates from Juergen Gross: - a series for the Xen pv block drivers adding module parameters for better control of resource usge - a cleanup series for the Xen event driver * tag 'for-linus-5.10b-rc1c-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: Documentation: add xen.fifo_events kernel parameter description xen/events: unmask a fifo event channel only if it was masked xen/events: only register debug interrupt for 2-level events xen/events: make struct irq_info private to events_base.c xen: remove no longer used functions xen-blkfront: Apply changed parameter name to the document xen-blkfront: add a parameter for disabling of persistent grants xen-blkback: add a parameter for disabling of persistent grants
2020-10-25Merge tag 'safesetid-5.10' of git://github.com/micah-morton/linuxLinus Torvalds1-9/+20
Pull SafeSetID updates from Micah Morton: "The changes are mostly contained to within the SafeSetID LSM, with the exception of a few 1-line changes to change some ns_capable() calls to ns_capable_setid() -- causing a flag (CAP_OPT_INSETID) to be set that is examined by SafeSetID code and nothing else in the kernel. The changes to SafeSetID internally allow for setting up GID transition security policies, as already existed for UIDs" * tag 'safesetid-5.10' of git://github.com/micah-morton/linux: LSM: SafeSetID: Fix warnings reported by test bot LSM: SafeSetID: Add GID security policy handling LSM: Signal to SafeSetID when setting group IDs
2020-10-23Merge tag 'docs-5.10-2' of git://git.lwn.net/linuxLinus Torvalds2-30/+35
Pull documentation fixes from Jonathan Corbet: "A handful of late-arriving documentation fixes" * tag 'docs-5.10-2' of git://git.lwn.net/linux: docs: Add two missing entries in vm sysctl index docs/vm: trivial fixes to several spelling mistakes docs: submitting-patches: describe preserving review/test tags Documentation: Chinese translation of Documentation/arm64/hugetlbpage.rst Documentation: x86: fix a missing word in x86_64/mm.rst. docs: driver-api: remove a duplicated index entry docs: lkdtm: Modernize and improve details docs: deprecated.rst: Expand str*cpy() replacement notes docs/cpu-load: format the example code.
2020-10-23Documentation: add xen.fifo_events kernel parameter descriptionJuergen Gross1-0/+7
The kernel boot parameter xen.fifo_events isn't listed in Documentation/admin-guide/kernel-parameters.txt. Add it. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Link: https://lore.kernel.org/r/20201022094907.28560-6-jgross@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-10-22docs: Add two missing entries in vm sysctl indexFam Zheng1-0/+2
Both seem overlooked while adding the section in the main content. Signed-off-by: Fam Zheng <famzheng@amazon.com> Link: https://lore.kernel.org/r/20201022065403.3936070-1-fam@euphon.net Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-10-22Merge tag 'nfsd-5.10' of git://linux-nfs.org/~bfields/linuxLinus Torvalds2-71/+0
Pull nfsd updates from Bruce Fields: "The one new feature this time, from Anna Schumaker, is READ_PLUS, which has the same arguments as READ but allows the server to return an array of data and hole extents. Otherwise it's a lot of cleanup and bugfixes" * tag 'nfsd-5.10' of git://linux-nfs.org/~bfields/linux: (43 commits) NFSv4.2: Fix NFS4ERR_STALE error when doing inter server copy SUNRPC: fix copying of multiple pages in gss_read_proxy_verf() sunrpc: raise kernel RPC channel buffer size svcrdma: fix bounce buffers for unaligned offsets and multiple pages nfsd: remove unneeded break net/sunrpc: Fix return value for sysctl sunrpc.transports NFSD: Encode a full READ_PLUS reply NFSD: Return both a hole and a data segment NFSD: Add READ_PLUS hole segment encoding NFSD: Add READ_PLUS data support NFSD: Hoist status code encoding into XDR encoder functions NFSD: Map nfserr_wrongsec outside of nfsd_dispatch NFSD: Remove the RETURN_STATUS() macro NFSD: Call NFSv2 encoders on error returns NFSD: Fix .pc_release method for NFSv2 NFSD: Remove vestigial typedefs NFSD: Refactor nfsd_dispatch() error paths NFSD: Clean up nfsd_dispatch() variables NFSD: Clean up stale comments in nfsd_dispatch() NFSD: Clean up switch statement in nfsd_dispatch() ...
2020-10-21docs/cpu-load: format the example code.Hui Su1-30/+33
format the example code. Signed-off-by: Hui Su <sh_def@163.com> Link: https://lore.kernel.org/r/20201018170557.GA7670@rlk Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-10-20Merge tag 'for-linus-5.10b-rc1b-tag' of ↵Linus Torvalds1-0/+8
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull more xen updates from Juergen Gross: - A single patch to fix the Xen security issue XSA-331 (malicious guests can DoS dom0 by triggering NULL-pointer dereferences or access to stale data). - A larger series to fix the Xen security issue XSA-332 (malicious guests can DoS dom0 by sending events at high frequency leading to dom0's vcpus being busy in IRQ handling for elongated times). * tag 'for-linus-5.10b-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/events: block rogue events for some time xen/events: defer eoi in case of excessive number of events xen/events: use a common cpu hotplug hook for event channels xen/events: switch user event channels to lateeoi model xen/pciback: use lateeoi irq binding xen/pvcallsback: use lateeoi irq binding xen/scsiback: use lateeoi irq binding xen/netback: use lateeoi irq binding xen/blkback: use lateeoi irq binding xen/events: add a new "late EOI" evtchn framework xen/events: fix race in evtchn_fifo_unmask() xen/events: add a proper barrier to 2-level uevent unmasking xen/events: avoid removing an event channel while handling it
2020-10-20xen/events: defer eoi in case of excessive number of eventsJuergen Gross1-0/+8
In case rogue guests are sending events at high frequency it might happen that xen_evtchn_do_upcall() won't stop processing events in dom0. As this is done in irq handling a crash might be the result. In order to avoid that, delay further inter-domain events after some time in xen_evtchn_do_upcall() by forcing eoi processing into a worker on the same cpu, thus inhibiting new events coming in. The time after which eoi processing is to be delayed is configurable via a new module parameter "event_loop_timeout" which specifies the maximum event loop time in jiffies (default: 2, the value was chosen after some tests showing that a value of 2 was the lowest with an only slight drop of dom0 network throughput while multiple guests performed an event storm). How long eoi processing will be delayed can be specified via another parameter "event_eoi_delay" (again in jiffies, default 10, again the value was chosen after testing with different delay values). This is part of XSA-332. Cc: stable@vger.kernel.org Reported-by: Julien Grall <julien@xen.org> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Wei Liu <wl@xen.org>
2020-10-19Merge tag 'xfs-5.10-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds1-1/+31
Pull more xfs updates from Darrick Wong: "The second large pile of new stuff for 5.10, with changes even more monumental than last week! We are formally announcing the deprecation of the V4 filesystem format in 2030. All users must upgrade to the V5 format, which contains design improvements that greatly strengthen metadata validation, supports reflink and online fsck, and is the intended vehicle for handling timestamps past 2038. We're also deprecating the old Irix behavioral tweaks in September 2025. Coming along for the ride are two design changes to the deferred metadata ops subsystem. One of the improvements is to retain correct logical ordering of tasks and subtasks, which is a more logical design for upper layers of XFS and will become necessary when we add atomic file range swaps and commits. The second improvement to deferred ops improves the scalability of the log by helping the log tail to move forward during long-running operations. This reduces log contention when there are a large number of threads trying to run transactions. In addition to that, this fixes numerous small bugs in log recovery; refactors logical intent log item recovery to remove the last remaining place in XFS where we could have nested transactions; fixes a couple of ways that intent log item recovery could fail in ways that wouldn't have happened in the regular commit paths; fixes a deadlock vector in the GETFSMAP implementation (which improves its performance by 20%); and fixes serious bugs in the realtime growfs, fallocate, and bitmap handling code. Summary: - Deprecate the V4 filesystem format, some disused mount options, and some legacy sysctl knobs now that we can support dates into the 25th century. Note that removal of V4 support will not happen until the early 2030s. - Fix some probles with inode realtime flag propagation. - Fix some buffer handling issues when growing a rt filesystem. - Fix a problem where a BMAP_REMAP unmap call would free rt extents even though the purpose of BMAP_REMAP is to avoid freeing the blocks. - Strengthen the dabtree online scrubber to check hash values on child dabtree blocks. - Actually log new intent items created as part of recovering log intent items. - Fix a bug where quotas weren't attached to an inode undergoing bmap intent item recovery. - Fix a buffer overrun problem with specially crafted log buffer headers. - Various cleanups to type usage and slightly inaccurate comments. - More cleanups to the xattr, log, and quota code. - Don't run the (slower) shared-rmap operations on attr fork mappings. - Fix a bug where we failed to check the LSN of finobt blocks during replay and could therefore overwrite newer data with older data. - Clean up the ugly nested transaction mess that log recovery uses to stage intent item recovery in the correct order by creating a proper data structure to capture recovered chains. - Use the capture structure to resume intent item chains with the same log space and block reservations as when they were captured. - Fix a UAF bug in bmap intent item recovery where we failed to maintain our reference to the incore inode if the bmap operation needed to relog itself to continue. - Rearrange the defer ops mechanism to finish newly created subtasks of a parent task before moving on to the next parent task. - Automatically relog intent items in deferred ops chains if doing so would help us avoid pinning the log tail. This will help fix some log scaling problems now and will facilitate atomic file updates later. - Fix a deadlock in the GETFSMAP implementation by using an internal memory buffer to reduce indirect calls and copies to userspace, thereby improving its performance by ~20%. - Fix various problems when calling growfs on a realtime volume would not fully update the filesystem metadata. - Fix broken Kconfig asking about deprecated XFS when XFS is disabled" * tag 'xfs-5.10-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (48 commits) xfs: fix Kconfig asking about XFS_SUPPORT_V4 when XFS_FS=n xfs: fix high key handling in the rt allocator's query_range function xfs: annotate grabbing the realtime bitmap/summary locks in growfs xfs: make xfs_growfs_rt update secondary superblocks xfs: fix realtime bitmap/summary file truncation when growing rt volume xfs: fix the indent in xfs_trans_mod_dquot xfs: do the ASSERT for the arguments O_{u,g,p}dqpp xfs: fix deadlock and streamline xfs_getfsmap performance xfs: limit entries returned when counting fsmap records xfs: only relog deferred intent items if free space in the log gets low xfs: expose the log push threshold xfs: periodically relog deferred intent items xfs: change the order in which child and parent defer ops are finished xfs: fix an incore inode UAF in xfs_bui_recover xfs: clean up xfs_bui_item_recover iget/trans_alloc/ilock ordering xfs: clean up bmap intent item recovery checking xfs: xfs_defer_capture should absorb remaining transaction reservation xfs: xfs_defer_capture should absorb remaining block reservations xfs: proper replay of deferred ops queued during log recovery xfs: remove XFS_LI_RECOVERED ...
2020-10-18Merge tag 'core-rcu-2020-10-12' of ↵Linus Torvalds1-18/+135
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU changes from Ingo Molnar: - Debugging for smp_call_function() - RT raw/non-raw lock ordering fixes - Strict grace periods for KASAN - New smp_call_function() torture test - Torture-test updates - Documentation updates - Miscellaneous fixes [ This doesn't actually pull the tag - I've dropped the last merge from the RCU branch due to questions about the series. - Linus ] * tag 'core-rcu-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (77 commits) smp: Make symbol 'csd_bug_count' static kernel/smp: Provide CSD lock timeout diagnostics smp: Add source and destination CPUs to __call_single_data rcu: Shrink each possible cpu krcp rcu/segcblist: Prevent useless GP start if no CBs to accelerate torture: Add gdb support rcutorture: Allow pointer leaks to test diagnostic code rcutorture: Hoist OOM registry up one level refperf: Avoid null pointer dereference when buf fails to allocate rcutorture: Properly synchronize with OOM notifier rcutorture: Properly set rcu_fwds for OOM handling torture: Add kvm.sh --help and update help message rcutorture: Add CONFIG_PROVE_RCU_LIST to TREE05 torture: Update initrd documentation rcutorture: Replace HTTP links with HTTPS ones locktorture: Make function torture_percpu_rwsem_init() static torture: document --allcpus argument added to the kvm.sh script rcutorture: Output number of elapsed grace periods rcutorture: Remove KCSAN stubs rcu: Remove unused "cpu" parameter from rcu_report_qs_rdp() ...
2020-10-16Merge tag 'docs/v5.10-1' of ↵Linus Torvalds2-14/+7
git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media Pull documentation updates from Mauro Carvalho Chehab: "A series of patches addressing warnings produced by make htmldocs. This includes: - kernel-doc markup fixes - ReST fixes - Updates at the build system in order to support newer versions of the docs build toolchain (Sphinx) After this series, the number of html build warnings should reduce significantly, and building with Sphinx 3.1 or later should now be supported (although it is still recommended to use Sphinx 2.4.4). As agreed with Jon, I should be sending you a late pull request by the end of the merge window addressing remaining issues with docs build, as there are a number of warning fixes that depends on pull requests that should be happening along the merge window. The end goal is to have a clean htmldocs build on Kernel 5.10. PS. It should be noticed that Sphinx 3.0 is not currently supported, as it lacks support for C domain namespaces. Such feature, needed in order to document uAPI system calls with Sphinx 3.x, was added only on Sphinx 3.1" * tag 'docs/v5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (75 commits) PM / devfreq: remove a duplicated kernel-doc markup mm/doc: fix a literal block markup workqueue: fix a kernel-doc warning docs: virt: user_mode_linux_howto_v2.rst: fix a literal block markup Input: sparse-keymap: add a description for @sw rcu/tree: docs: document bkvcache new members at struct kfree_rcu_cpu nl80211: docs: add a description for s1g_cap parameter usb: docs: document altmode register/unregister functions kunit: test.h: fix a bad kernel-doc markup drivers: core: fix kernel-doc markup for dev_err_probe() docs: bio: fix a kerneldoc markup kunit: test.h: solve kernel-doc warnings block: bio: fix a warning at the kernel-doc markups docs: powerpc: syscall64-abi.rst: fix a malformed table drivers: net: hamradio: fix document location net: appletalk: Kconfig: Fix docs location dt-bindings: fix references to files converted to yaml memblock: get rid of a :c:type leftover math64.h: kernel-docs: Convert some markups into normal comments media: uAPI: buffer.rst: remove a left-over documentation ...
2020-10-16Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-0/+1
Merge more updates from Andrew Morton: "155 patches. Subsystems affected by this patch series: mm (dax, debug, thp, readahead, page-poison, util, memory-hotplug, zram, cleanups), misc, core-kernel, get_maintainer, MAINTAINERS, lib, bitops, checkpatch, binfmt, ramfs, autofs, nilfs, rapidio, panic, relay, kgdb, ubsan, romfs, and fault-injection" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (155 commits) lib, uaccess: add failure injection to usercopy functions lib, include/linux: add usercopy failure capability ROMFS: support inode blocks calculation ubsan: introduce CONFIG_UBSAN_LOCAL_BOUNDS for Clang sched.h: drop in_ubsan field when UBSAN is in trap mode scripts/gdb/tasks: add headers and improve spacing format scripts/gdb/proc: add struct mount & struct super_block addr in lx-mounts command kernel/relay.c: drop unneeded initialization panic: dump registers on panic_on_warn rapidio: fix the missed put_device() for rio_mport_add_riodev rapidio: fix error handling path nilfs2: fix some kernel-doc warnings for nilfs2 autofs: harden ioctl table ramfs: fix nommu mmap with gaps in the page cache mm: remove the now-unnecessary mmget_still_valid() hack mm/gup: take mmap_lock in get_dump_page() binfmt_elf, binfmt_elf_fdpic: use a VMA list snapshot coredump: rework elf/elf_fdpic vma_dump_size() into common helper coredump: refactor page range dumping into common helper coredump: let dump_emit() bail out on short writes ...
2020-10-16lib, include/linux: add usercopy failure capabilityAlbert van der Linde