linux/Documentation/admin-guide, branch v5.10

Merge tag 'trace-v5.10-rc6-bootconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2020-12-02T20:09:36Z

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

Merge tag 'trace-v5.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2020-12-01T23:30:18Z

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()

docs: bootconfig: Add the endianness of fields

2020-12-01T04:22:11Z

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 Suggested-by: Linus Torvalds Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

Merge tag 'powerpc-cve-2020-4788' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2020-11-19T19:32:31Z

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

docs: bootconfig: Update file format on initrd image

2020-11-19T13:55:44Z

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 Signed-off-by: Steven Rostedt (VMware)

powerpc/64s: flush L1D after user accesses

2020-11-19T12:47:18Z

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 Signed-off-by: Daniel Axtens Signed-off-by: Michael Ellerman

powerpc/64s: flush L1D on kernel entry

2020-11-19T12:47:15Z

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 Signed-off-by: Daniel Axtens Signed-off-by: Michael Ellerman

Merge tag 'pm-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2020-11-05T19:04:29Z

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()

Merge tag 'docs-5.10-warnings' of git://git.lwn.net/linux

2020-11-03T21:14:14Z

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 ...

Documentation: PM: cpuidle: correct path name

2020-11-02T17:02:20Z

cpu/ is needed before cpu/ Signed-off-by: Julia Lawall Signed-off-by: Rafael J. Wysocki