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2020-09-22dm crypt: document new no_workqueue flagsMilan Broz1-0/+8
Commit 39d42fa96ba1 ("dm crypt: add flags to optionally bypass kcryptd workqueues") introduced new dm-crypt 'no_read_workqueue' and 'no_write_workqueue' flags. Add documentation to admin guide for them. Fixes: 39d42fa96ba1 ("dm crypt: add flags to optionally bypass kcryptd workqueues") Signed-off-by: Milan Broz <[email protected]> Signed-off-by: Mike Snitzer <[email protected]>
2020-09-22printk: move dictionary keys to dev_printk_infoJohn Ogness1-40/+33
Dictionaries are only used for SUBSYSTEM and DEVICE properties. The current implementation stores the property names each time they are used. This requires more space than otherwise necessary. Also, because the dictionary entries are currently considered optional, it cannot be relied upon that they are always available, even if the writer wanted to store them. These issues will increase should new dictionary properties be introduced. Rather than storing the subsystem and device properties in the dict ring, introduce a struct dev_printk_info with separate fields to store only the property values. Embed this struct within the struct printk_info to provide guaranteed availability. Signed-off-by: John Ogness <[email protected]> Reviewed-by: Petr Mladek <[email protected]> Signed-off-by: Petr Mladek <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16docs: rewrite admin-guide/sysctl/abi.rstStephen Kitt1-53/+18
Following the structure used in sysctl/kernel.rst, this updates abi.rst to use ReStructured Text more fully and updates the entries to match current kernels: * the list of files is now the table of contents; * links are used to point to other documentation and other sections; * all the existing entries are no longer present, so this removes them; * document vsyscall32. Mentions of the kernel version are dropped. Since the document is entirely rewritten, I've replaced the copyright statement. Signed-off-by: Stephen Kitt <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jonathan Corbet <[email protected]>
2020-09-16Documentation: arm64 also supports disable hugeiomapTian Tao1-1/+1
arm64 also supports disable hugeiomap,updated documentation. Signed-off-by: Tian Tao <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jonathan Corbet <[email protected]>
2020-09-15xfs: deprecate the V4 formatDarrick J. Wong1-0/+23
The V4 filesystem format contains known weaknesses in the on-disk format that make metadata verification diffiult. In addition, the format does not support dates past 2038 and will not be upgraded to do so. We should start the process of retiring the old format to close off attack surfaces and to encourage users to migrate onto V5. Therefore, make XFS V4 support a configurable option. For the first period it will be default Y in case some distributors want to withdraw support early; for the second period it will be default N so that anyone who wishes to continue support can do so; and after that, support will be removed from the kernel. Dates for these events have been added to the upstream kernel. Signed-off-by: Darrick J. Wong <[email protected]> Reviewed-by: Dave Chinner <[email protected]> Reviewed-by: Eric Sandeen <[email protected]>
2020-09-15printk: ringbuffer: add finalization/extension supportJohn Ogness1-1/+2
Add support for extending the newest data block. For this, introduce a new finalization state (desc_finalized) denoting a committed descriptor that cannot be extended. Until a record is finalized, a writer can reopen that record to append new data. Reopening a record means transitioning from the desc_committed state back to the desc_reserved state. A writer can explicitly finalize a record if there is no intention of extending it. Also, records are automatically finalized when a new record is reserved. This relieves writers of needing to explicitly finalize while also making such records available to readers sooner. (Readers can only traverse finalized records.) Four new memory barrier pairs are introduced. Two of them are insignificant additions (data_realloc:A/desc_read:D and data_realloc:A/data_push_tail:B) because they are alternate path memory barriers that exactly match the purpose, pairing, and context of the two existing memory barrier pairs they provide an alternate path for. The other two new memory barrier pairs are significant additions: desc_reopen_last:A / _prb_commit:B - When reopening a descriptor, ensure the state transitions back to desc_reserved before fully trusting the descriptor data. _prb_commit:B / desc_reserve:D - When committing a descriptor, ensure the state transitions to desc_committed before checking the head ID to see if the descriptor needs to be finalized. Signed-off-by: John Ogness <[email protected]> Reviewed-by: Petr Mladek <[email protected]> Signed-off-by: Petr Mladek <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-15printk: ringbuffer: change representation of statesJohn Ogness1-4/+8
Rather than deriving the state by evaluating bits within the flags area of the state variable, assign the states explicit values and set those values in the flags area. Introduce macros to make it simple to read and write state values for the state variable. Although the functionality is preserved, the binary representation for the states is changed. Signed-off-by: John Ogness <[email protected]> Reviewed-by: Petr Mladek <[email protected]> Signed-off-by: Petr Mladek <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-13Merge tag 'char-misc-5.9-rc5' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char / misc driver fixes from Greg KH: "Here are a number of small driver fixes for 5.9-rc5 Included in here are: - habanalabs driver fixes - interconnect driver fixes - soundwire driver fixes - dyndbg fixes for reported issues, and then reverts to fix it all up to a sane state. - phy driver fixes All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: Revert "dyndbg: accept query terms like file=bar and module=foo" Revert "dyndbg: fix problem parsing format="foo bar"" scripts/tags.sh: exclude tools directory from tags generation video: fbdev: fix OOB read in vga_8planes_imageblit() dyndbg: fix problem parsing format="foo bar" dyndbg: refine export, rename to dynamic_debug_exec_queries() dyndbg: give %3u width in pr-format, cosmetic only interconnect: qcom: Fix small BW votes being truncated to zero soundwire: fix double free of dangling pointer interconnect: Show bandwidth for disabled paths as zero in debugfs habanalabs: fix report of RAZWI initiator coordinates habanalabs: prevent user buff overflow phy: omap-usb2-phy: disable PHY charger detect phy: qcom-qmp: Use correct values for ipq8074 PCIe Gen2 PHY init soundwire: bus: fix typo in comment on INTSTAT registers phy: qualcomm: fix return value check in qcom_ipq806x_usb_phy_probe() phy: qualcomm: fix platform_no_drv_owner.cocci warnings
2020-09-10Revert "dyndbg: accept query terms like file=bar and module=foo"Greg Kroah-Hartman1-1/+0
This reverts commit 14775b04964264189caa4a0862eac05dab8c0502 as there were still some parsing problems with it, and the follow-on patch for it. Let's revisit it later, just drop it for now. Cc: <[email protected]> Cc: Jim Cromie <[email protected]> Reported-by: Naresh Kamboju <[email protected]> Cc: Stephen Rothwell <[email protected]> Fixes: 14775b049642 ("dyndbg: accept query terms like file=bar and module=foo") Signed-off-by: Greg Kroah-Hartman <[email protected]>
2020-09-10x86/fpu: Allow multiple bits in clearcpuid= parameterArvind Sankar1-1/+1
Commit 0c2a3913d6f5 ("x86/fpu: Parse clearcpuid= as early XSAVE argument") changed clearcpuid parsing from __setup() to cmdline_find_option(). While the __setup() function would have been called for each clearcpuid= parameter on the command line, cmdline_find_option() will only return the last one, so the change effectively made it impossible to disable more than one bit. Allow a comma-separated list of bit numbers as the argument for clearcpuid to allow multiple bits to be disabled again. Log the bits being disabled for informational purposes. Also fix the check on the return value of cmdline_find_option(). It returns -1 when the option is not found, so testing as a boolean is incorrect. Fixes: 0c2a3913d6f5 ("x86/fpu: Parse clearcpuid= as early XSAVE argument") Signed-off-by: Arvind Sankar <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-09-10media: usbvision: remove deprecated driverHans Verkuil2-284/+0
To quote the TODO of this driver: -------------------------------------------------------------- The driver is deprecated and scheduled for removal by the end of 2020. In order to prevent removal the following actions would have to be taken: - clean up the code - convert to the vb2 framework - fix the disconnect and free-on-last-user handling (i.e., add a release callback for struct v4l2_device and rework the code to use that correctly). -------------------------------------------------------------- Nobody picked this up, so it's time to retire this driver. Signed-off-by: Hans Verkuil <[email protected]> Signed-off-by: Mauro Carvalho Chehab <[email protected]>
2020-09-09mm/doc: editorial pass on page migrationRalph Campbell1-0/+2
Add Sphinx reference links to HMM and CPUSETS, and numerous small editorial changes to make the page_migration.rst document more readable. Signed-off-by: Ralph Campbell <[email protected]> Reviewed-by: Randy Dunlap <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jonathan Corbet <[email protected]>
2020-09-09bcache: doc: update Documentation/admin-guide/bcache.rstColy Li1-12/+19
bcache.rst is from the original bcache.txt which was merged in mainline kernel v3.10. There are a few things changed in the past 7 years. This patch updates bache.rst documents in following content, - Update bcache-tools git repo to, https://git.kernel.org/pub/scm/linux/kernel/git/colyli/bcache-tools.git/ - Update bcache kernel tree to mainline kernel tree, https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ - make-bcache util is replaced by the unified bcache util, `make-bcache` now can be performed by `bcache make` Signed-off-by: Coly Li <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Kent Overstreet <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jonathan Corbet <[email protected]>
2020-09-08scripts/gdb: update for lockless printk ringbufferJohn Ogness1-46/+107
With the introduction of the lockless printk ringbuffer, the data structure for the kernel log buffer was changed. Update the gdb scripts to be able to parse/print the new log buffer structure. Fixes: 896fbe20b4e2333fb55 ("printk: use the lockless ringbuffer") Signed-off-by: John Ogness <[email protected]> Reported-by: Nick Desaulniers <[email protected]> Tested-by: Nick Desaulniers <[email protected]> Tested-by: Petr Mladek <[email protected]> [[email protected]: A typo fix.] Signed-off-by: Petr Mladek <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-08docs: vmcoreinfo: add lockless printk ringbuffer vmcoreinfoJohn Ogness1-29/+102
With the introduction of the lockless printk ringbuffer, the VMCOREINFO relating to the kernel log buffer was changed. Update the documentation to match those changes. Fixes: 896fbe20b4e2333fb55 ("printk: use the lockless ringbuffer") Reported-by: Nick Desaulniers <[email protected]> Signed-off-by: John Ogness <[email protected]> Reviewed-by: Petr Mladek <[email protected]> Signed-off-by: Petr Mladek <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-07Merge tag 'v5.9-rc4' into patchworkMauro Carvalho Chehab5-19/+21
Linux 5.9-rc4 * tag 'v5.9-rc4': (1001 commits) Linux 5.9-rc4 io_uring: fix linked deferred ->files cancellation io_uring: fix cancel of deferred reqs with ->files include/linux/log2.h: add missing () around n in roundup_pow_of_two() mm/khugepaged.c: fix khugepaged's request size in collapse_file mm/hugetlb: fix a race between hugetlb sysctl handlers mm/hugetlb: try preferred node first when alloc gigantic page from cma mm/migrate: preserve soft dirty in remove_migration_pte() mm/migrate: remove unnecessary is_zone_device_page() check mm/rmap: fixup copying of soft dirty and uffd ptes mm/migrate: fixup setting UFFD_WP flag mm: madvise: fix vma user-after-free checkpatch: fix the usage of capture group ( ... ) fork: adjust sysctl_max_threads definition to match prototype ipc: adjust proc_ipc_sem_dointvec definition to match prototype mm: track page table modifications in __apply_to_page_range() MAINTAINERS: IA64: mark Status as Odd Fixes only MAINTAINERS: add LLVM maintainers MAINTAINERS: update Cavium/Marvell entries mm: slub: fix conversion of freelist_corrupted() ...
2020-09-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski3-5/+7
We got slightly different patches removing a double word in a comment in net/ipv4/raw.c - picked the version from net. Simple conflict in drivers/net/ethernet/ibm/ibmvnic.c. Use cached values instead of VNIC login response buffer (following what commit 507ebe6444a4 ("ibmvnic: Fix use-after-free of VNIC login response buffer") did). Signed-off-by: Jakub Kicinski <[email protected]>
2020-09-04Merge tag 'pm-5.9-rc4' of ↵Linus Torvalds1-1/+3
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fixes from Rafael Wysocki: "These fix reference counting in the operating performance points (OPP) framework and address a few intel_pstate driver issues, mostly related to switching driver operation modes and similar with hardware-managed P-states (HWP) enabled. Specifics: - Fix reference counting of operating performance points (OPP) tables (Viresh Kumar). - Address intel_pstate driver interface issues, mostly related to switching operation modes and handling CPU offline and online and system-wide suspend/resume with hardware-managed P-states (HWP) enabled (Rafael Wysocki). - Fix the maximum frequency computation in the intel_pstate driver with turbo P-states disabled by the platform firmware and HWP enabled (Francisco Jerez)" * tag 'pm-5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpufreq: intel_pstate: Fix intel_pstate_get_hwp_max() for turbo disabled cpufreq: intel_pstate: Free memory only when turning off cpufreq: intel_pstate: Add ->offline and ->online callbacks cpufreq: intel_pstate: Tweak the EPP sysfs interface cpufreq: intel_pstate: Update cached EPP in the active mode cpufreq: intel_pstate: Refuse to turn off with HWP enabled opp: Don't drop reference for an OPP table that was never parsed
2020-09-04Merge branch 'csd.2020.09.04a' into HEADPaul E. McKenney1-0/+4
csd.2020.09.04a: CPU smp_call_function() torture tests.
2020-09-03Merge branch 'strictgp.2020.08.24a' into HEADPaul E. McKenney1-0/+9
strictgp.2020.08.24a: Strict grace periods for KASAN testing.
2020-09-03Merge branch 'scftorture.2020.08.24a' into HEADPaul E. McKenney1-18/+110
scftorture.2020.08.24a: Torture tests for smp_call_function() and friends.
2020-09-01cpufreq: intel_pstate: Tweak the EPP sysfs interfaceRafael J. Wysocki1-1/+3
Modify the EPP sysfs interface to reject attempts to change the EPP to values different from 0 ("performance") in the active mode with the "performance" policy (ie. scaling_governor set to "performance"), to avoid situations in which the kernel appears to discard data passed to it via the EPP sysfs attribute. Signed-off-by: Rafael J. Wysocki <[email protected]> Reviewed-by: Artem Bityutskiy <[email protected]> Acked-by: Srinivas Pandruvada <[email protected]>
2020-09-01media: ipu3.rst: Format media-ctl and yavta commands as code blocksJordan Hand1-49/+55
Fix improper line breaks and format all example yavta and media-ctl commands as code blocks to improve readability. Signed-off-by: Jordan Hand <[email protected]> Signed-off-by: Sakari Ailus <[email protected]> Signed-off-by: Mauro Carvalho Chehab <[email protected]>
2020-09-01dma-contiguous: provide the ability to reserve per-numa CMABarry Song1-0/+11
Right now, drivers like ARM SMMU are using dma_alloc_coherent() to get coherent DMA buffers to save their command queues and page tables. As there is only one default CMA in the whole system, SMMUs on nodes other than node0 will get remote memory. This leads to significant latency. This patch provides per-numa CMA so that drivers like SMMU can get local memory. Tests show localizing CMA can decrease dma_unmap latency much. For instance, before this patch, SMMU on node2 has to wait for more than 560ns for the completion of CMD_SYNC in an empty command queue; with this patch, it needs 240ns only. A positive side effect of this patch would be improving performance even further for those users who are worried about performance more than DMA security and use iommu.passthrough=1 to skip IOMMU. With local CMA, all drivers can get local coherent DMA buffers. Also, this patch changes the default CONFIG_CMA_AREAS to 19 in NUMA. As 1+CONFIG_CMA_AREAS should be quite enough for most servers on the market even they enable both hugetlb_cma and pernuma_cma. 2 numa nodes: 2(hugetlb) + 2(pernuma) + 1(default global cma) = 5 4 numa nodes: 4(hugetlb) + 4(pernuma) + 1(default global cma) = 9 8 numa nodes: 8(hugetlb) + 8(pernuma) + 1(default global cma) = 17 Signed-off-by: Barry Song <[email protected]> Signed-off-by: Christoph Hellwig <[email protected]>
2020-08-31Merge tag 'docs-5.9-3' of git://git.lwn.net/linuxLinus Torvalds2-2/+2
Pull documentation fixes from Jonathan Corbet: "A handful of documentation fixes for 5.9" * tag 'docs-5.9-3' of git://git.lwn.net/linux: Documentation: laptops: thinkpad-acpi: fix underline length build warning Documentation: fix typo for abituguru documentation docs: Fix function name trailing double-()s devices.txt: fix typo of "ubd" as "udb" Documentation: add riscv entry in list of existing profiles MAINTAINERS: mention documentation maintainer entry profile Fpga: Documentation: Replace deprecated :c:func: Usage IIO: Documentation: Replace deprecated :c:func: Usage Documentation/locking/locktypes: fix local_locks documentation
2020-08-28Merge branch 'pm-cpufreq'Rafael J. Wysocki1-2/+2
* pm-cpufreq: cpufreq: Use WARN_ON_ONCE() for invalid relation cpufreq: No need to verify cpufreq_driver in show_scaling_cur_freq() Documentation: fix pm/intel_pstate build warning and wording cpufreq: replace cpu_logical_map() with read_cpuid_mpir()
2020-08-28net: add option to not create fall-back tunnels in root-ns as wellMahesh Bandewar2-6/+19
The sysctl that was added earlier by commit 79134e6ce2c ("net: do not create fallback tunnels for non-default namespaces") to create fall-back only in root-ns. This patch enhances that behavior to provide option not to create fallback tunnels in root-ns as well. Since modules that create fallback tunnels could be built-in and setting the sysctl value after booting is pointless, so added a kernel cmdline options to change this default. The default setting is preseved for backward compatibility. The kernel command line option of fb_tunnels=initns will set the sysctl value to 1 and will create fallback tunnels only in initns while kernel cmdline fb_tunnels=none will set the sysctl value to 2 and fallback tunnels are skipped in every netns. Signed-off-by: Mahesh Bandewar <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Maciej Zenczykowski <[email protected]> Cc: Jian Yang <[email protected]> Cc: Randy Dunlap <[email protected]> Signed-off-by: David S. Miller <[email protected]>
2020-08-24rcutorture: Allow pointer leaks to test diagnostic codePaul E. McKenney1-0/+12
This commit adds an rcutorture.leakpointer module parameter that intentionally leaks an RCU-protected pointer out of the RCU read-side critical section and checks to see if the corresponding grace period has elapsed, emitting a WARN_ON_ONCE() if so. This module parameter can be used to test facilities like CONFIG_RCU_STRICT_GRACE_PERIOD that end grace periods quickly. While in the area, also document rcutorture.irqreader, which was previously left out. Reported-by Jann Horn <[email protected]> Signed-off-by: Paul E. McKenney <[email protected]>
2020-08-24rcu: Provide optional RCU-reader exit delay for strict GPsPaul E. McKenney1-0/+9
The goal of this series is to increase the probability of tools like KASAN detecting that an RCU-protected pointer was used outside of its RCU read-side critical section. Thus far, the approach has been to make grace periods and callback processing happen faster. Another approach is to delay the pointer leaker. This commit therefore allows a delay to be applied to exit from RCU read-side critical sections. This slowdown is specified by a new rcutree.rcu_unlock_delay kernel boot parameter that specifies this delay in microseconds, defaulting to zero. Reported-by Jann Horn <[email protected]> Signed-off-by: Paul E. McKenney <[email protected]>
2020-08-24rcuperf: Change rcuperf to rcuscalePaul E. McKenney1-18/+18
This commit further avoids conflation of rcuperf with the kernel's perf feature by renaming kernel/rcu/rcuperf.c to kernel/rcu/rcuscale.c, and also by similarly renaming the functions and variables inside this file. This has the side effect of changing the names of the kernel boot parameters, so kernel-parameters.txt and ver_functions.sh are also updated. The rcutorture --torture type was also updated from rcuperf to rcuscale. [ paulmck: Fix bugs located by Stephen Rothwell. ] Reported-by: Ingo Molnar <[email protected]> Signed-off-by: Paul E. McKenney <[email protected]>
2020-08-24scftorture: Add smp_call_function() torture testPaul E. McKenney1-0/+92
This commit adds an smp_call_function() torture test that repeatedly invokes this function and complains if things go badly awry. Signed-off-by: Paul E. McKenney <[email protected]>
2020-08-24Documentation: laptops: thinkpad-acpi: fix underline length build warningRandy Dunlap1-1/+1
Fix underline length build warning in thinkpad-acpi.rst documentation: Documentation/admin-guide/laptops/thinkpad-acpi.rst:1437: WARNING: Title underline too short. DYTC Lapmode sensor ------------------ Fixes: acf7f4a59114 ("platform/x86: thinkpad_acpi: lap or desk mode interface") Signed-off-by: Randy Dunlap <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jonathan Corbet <[email protected]>
2020-08-24devices.txt: fix typo of "ubd" as "udb"Theodore Dubois1-1/+1
Signed-off-by: Theodore Dubois <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jonathan Corbet <[email protected]>
2020-08-24lib: Add backtrace_idle parameter to force backtrace of idle CPUsPaul E. McKenney1-0/+4
Currently, the nmi_cpu_backtrace() declines to produce backtraces for idle CPUs. This is a good choice in the common case in which problems are caused only by non-idle CPUs. However, there are occasionally situations in which idle CPUs are helping to cause problems. This commit therefore adds an nmi_backtrace.backtrace_idle kernel boot parameter that causes nmi_cpu_backtrace() to dump stacks even of idle CPUs. Signed-off-by: Paul E. McKenney <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: <[email protected]>
2020-08-24Documentation: fix pm/intel_pstate build warning and wordingRandy Dunlap1-2/+2
Fix documentation build warning and sentence wording: Documentation/admin-guide/pm/intel_pstate.rst:568: WARNING: Unexpected indentation. Fixes: f473bf398bf1 ("cpufreq: intel_pstate: Allow raw energy performance preference value") Signed-off-by: Randy Dunlap <[email protected]> Cc: Srinivas Pandruvada <[email protected]> Cc: Rafael J. Wysocki <[email protected]> Signed-off-by: Rafael J. Wysocki <[email protected]>
2020-08-23Merge tag 'efi-urgent-2020-08-23' of ↵Linus Torvalds1-4/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI fixes from Thomas Gleixner: - Enforce NX on RO data in mixed EFI mode - Destroy workqueue in an error handling path to prevent UAF - Stop argument parser at '--' which is the delimiter for init - Treat a NULL command line pointer as empty instead of dereferncing it unconditionally. - Handle an unterminated command line correctly - Cleanup the 32bit code leftovers and remove obsolete documentation * tag 'efi-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Documentation: efi: remove description of efi=old_map efi/x86: Move 32-bit code into efi_32.c efi/libstub: Handle unterminated cmdline efi/libstub: Handle NULL cmdline efi/libstub: Stop parsing arguments at "--" efi: add missed destroy_workqueue when efisubsys_init fails efi/x86: Mark kernel rodata non-executable for mixed mode
2020-08-21Merge tag 'ext4_for_linus' of ↵Linus Torvalds1-10/+13
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Improvements to ext4's block allocator performance for very large file systems, especially when the file system or files which are highly fragmented. There is a new mount option, prefetch_block_bitmaps which will pull in the block bitmaps and set up the in-memory buddy bitmaps when the file system is initially mounted. Beyond that, a lot of bug fixes and cleanups. In particular, a number of changes to make ext4 more robust in the face of write errors or file system corruptions" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (46 commits) ext4: limit the length of per-inode prealloc list ext4: reorganize if statement of ext4_mb_release_context() ext4: add mb_debug logging when there are lost chunks ext4: Fix comment typo "the the". jbd2: clean up checksum verification in do_one_pass() ext4: change to use fallthrough macro ext4: remove unused parameter of ext4_generic_delete_entry function mballoc: replace seq_printf with seq_puts ext4: optimize the implementation of ext4_mb_good_group() ext4: delete invalid comments near ext4_mb_check_limits() ext4: fix typos in ext4_mb_regular_allocator() comment ext4: fix checking of directory entry validity for inline directories fs: prevent BUG_ON in submit_bh_wbc() ext4: correctly restore system zone info when remount fails ext4: handle add_system_zone() failure in ext4_setup_system_zone() ext4: fold ext4_data_block_valid_rcu() into the caller ext4: check journal inode extents more carefully ext4: don't allow overlapping system zones ext4: handle error of ext4_setup_system_zone() on remount ext4: delete the invalid BUGON in ext4_mb_load_buddy_gfp() ...
2020-08-20Documentation: efi: remove description of efi=old_mapArd Biesheuvel1-4/+1
The old EFI runtime region mapping logic that was kept around for some time has finally been removed entirely, along with the SGI UV1 support code that was its last remaining user. So remove any mention of the efi=old_map command line parameter from the docs. Cc: Jonathan Corbet <[email protected]> Cc: [email protected] Signed-off-by: Ard Biesheuvel <[email protected]>
2020-08-19ext4: limit the length of per-inode prealloc listbrookxu1-0/+3
In the scenario of writing sparse files, the per-inode prealloc list may be very long, resulting in high overhead for ext4_mb_use_preallocated(). To circumvent this problem, we limit the maximum length of per-inode prealloc list to 512 and allow users to modify it. After patching, we observed that the sys ratio of cpu has dropped, and the system throughput has increased significantly. We created a process to write the sparse file, and the running time of the process on the fixed kernel was significantly reduced, as follows: Running time on unfixed kernel: [root@TENCENT64 ~]# time taskset 0x01 ./sparse /data1/sparce.dat real 0m2.051s user 0m0.008s sys 0m2.026s Running time on fixed kernel: [root@TENCENT64 ~]# time taskset 0x01 ./sparse /data1/sparce.dat real 0m0.471s user 0m0.004s sys 0m0.395s Signed-off-by: Chunguang Xu <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Theodore Ts'o <[email protected]>
2020-08-15Merge tag 'x86-urgent-2020-08-15' of ↵Linus Torvalds1-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes and small updates all around the place: - Fix mitigation state sysfs output - Fix an FPU xstate/sxave code assumption bug triggered by Architectural LBR support - Fix Lightning Mountain SoC TSC frequency enumeration bug - Fix kexec debug output - Fix kexec memory range assumption bug - Fix a boundary condition in the crash kernel code - Optimize porgatory.ro generation a bit - Enable ACRN guests to use X2APIC mode - Reduce a __text_poke() IRQs-off critical section for the benefit of PREEMPT_RT" * tag 'x86-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/alternatives: Acquire pte lock with interrupts enabled x86/bugs/multihit: Fix mitigation reporting when VMX is not in use x86/fpu/xstate: Fix an xstate size check warning with architectural LBRs x86/purgatory: Don't generate debug info for purgatory.ro x86/tsr: Fix tsc frequency enumeration bug on Lightning Mountain SoC kexec_file: Correctly output debugging information for the PT_LOAD ELF header kexec: Improve & fix crash_exclude_mem_range() to handle overlapping ranges x86/crash: Correct the address boundary of function parameters x86/acrn: Remove redundant chars from ACRN signature x86/acrn: Allow ACRN guest to use X2APIC mode
2020-08-15Merge tag 'pm-5.9-rc1-3' of ↵Linus Torvalds1-46/+43
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull one more power management update from Rafael Wysocki: "Modify the intel_pstate driver to allow it to work in the passive mode with hardware-managed P-states (HWP) enabled" * tag 'pm-5.9-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpufreq: intel_pstate: Implement passive mode with HWP enabled
2020-08-14Merge branch 'pm-cpufreq'Rafael J. Wysocki1-46/+43
* pm-cpufreq: cpufreq: intel_pstate: Implement passive mode with HWP enabled
2020-08-13Merge tag 'docs-5.9-2' of git://git.lwn.net/linuxLinus Torvalds1-18/+18
Pull documentation fixes from Jonathan Corbet: "A handful of obvious fixes that wandered in during the merge window" * tag 'docs-5.9-2' of git://git.lwn.net/linux: Documentation/locking/locktypes: fix the typo doc/zh_CN: resolve undefined label warning in admin-guide index doc/zh_CN: fix title heading markup in admin-guide cpu-load docs: remove the 2.6 "Upgrading I2C Drivers" guide docs: Correct the release date of 5.2 stable mailmap: Update comments for with format and more detalis docs: cdrom: Fix a typo and rst markup Doc: admin-guide: use correct legends in kernel-parameters.txt Documentation/features: refresh RISC-V arch support files documentation: coccinelle: Improve command example for make C={1,2} Core-api: Documentation: Replace deprecated :c:func: Usage Dev-tools: Documentation: Replace deprecated :c:func: Usage Filesystems: Documentation: Replace deprecated :c:func: Usage docs: trace: fix a typo
2020-08-12coredump: add %f for executable filenameLepton Wu1-1/+2
The document reads "%e" should be "executable filename" while actually it could be changed by things like pr_ctl PR_SET_NAME. People who uses "%e" in core_pattern get surprised when they find out they get thread name instead of executable filename. This is either a bug of document or a bug of code. Since the behavior of "%e" is there for long time, it could bring another surprise for users if we "fix" the code. So we just "fix" the document. And more, for users who really need the "executable filename" in core_pattern, we introduce a new "%f" for the real executable filename. We already have "%E" for executable path in kernel, so just reuse most of its code for the new added "%f" format. Signed-off-by: Lepton Wu <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-08-12mm: proactive compactionNitin Gupta1-0/+15
For some applications, we need to allocate almost all memory as hugepages. However, on a running system, higher-order allocations can fail if the memory is fragmented. Linux kernel currently does on-demand compaction as we request more hugepages, but this style of compaction incurs very high latency. Experiments with one-time full memory compaction (followed by hugepage allocations) show that kernel is able to restore a highly fragmented memory state to a fairly compacted memory state within <1 sec for a 32G system. Such data suggests that a more proactive compaction can help us allocate a large fraction of memory as hugepages keeping allocation latencies low. For a more proactive compaction, the approach taken here is to define a new sysctl called 'vm.compaction_proactiveness' which dictates bounds for external fragmentation which kcompactd tries to maintain. The tunable takes a value in range [0, 100], with a default of 20. Note that a previous version of this patch [1] was found to introduce too many tunables (per-order extfrag{low, high}), but this one reduces them to just one sysctl. Also, the new tunable is an opaque value instead of asking for specific bounds of "external fragmentation", which would have been difficult to estimate. The internal interpretation of this opaque value allows for future fine-tuning. Currently, we use a simple translation from this tunable to [low, high] "fragmentation score" thresholds (low=100-proactiveness, high=low+10%). The score for a node is defined as weighted mean of per-zone external fragmentation. A zone's present_pages determines its weight. To periodically check per-node score, we reuse per-node kcompactd threads, which are woken up every 500 milliseconds to check the same. If a node's score exceeds its high threshold (as derived from user-provided proactiveness value), proactive compaction is started until its score reaches its low threshold value. By default, proactiveness is set to 20, which implies threshold values of low=80 and high=90. This patch is largely based on ideas from Michal Hocko [2]. See also the LWN article [3]. Performance data ================ System: x64_64, 1T RAM, 80 CPU threads. Kernel: 5.6.0-rc3 + this patch echo madvise | sudo tee /sys/kernel/mm/transparent_hugepage/enabled echo madvise | sudo tee /sys/kernel/mm/transparent_hugepage/defrag Before starting the driver, the system was fragmented from a userspace program that allocates all memory and then for each 2M aligned section, frees 3/4 of base pages using munmap. The workload is mainly anonymous userspace pages, which are easy to move around. I intentionally avoided unmovable pages in this test to see how much latency we incur when hugepage allocations hit direct compaction. 1. Kernel hugepage allocation latencies With the system in such a fragmented state, a kernel driver then allocates as many hugepages as possible and measures allocation latency: (all latency values are in microseconds) - With vanilla 5.6.0-rc3 percentile latency –––––––––– ––––––– 5 7894 10 9496 25 12561 30 15295 40 18244 50 21229 60 27556 75 30147 80 31047 90 32859 95 33799 Total 2M hugepages allocated = 383859 (749G worth of hugepages out of 762G total free => 98% of free memory could be allocated as hugepages) - With 5.6.0-rc3 + this patch, with proactiveness=20 sysctl -w vm.compaction_proactiveness=20 percentile latency –––––––––– ––––––– 5 2 10 2 25 3 30 3 40 3 50 4 60 4 75 4 80 4 90 5 95 429 Total 2M hugepages allocated = 384105 (750G worth of hugepages out of 762G total free => 98% of free memory could be allocated as hugepages) 2. JAVA heap allocation In this test, we first fragment memory using the same method as for (1). Then, we start a Java process with a heap size set to 700G and request the heap to be allocated with THP hugepages. We also set THP to madvise to allow hugepage backing of this heap. /usr/bin/time java -Xms700G -Xmx700G -XX:+UseTransparentHugePages -XX:+AlwaysPreTouch The above command allocates 700G of Java heap using hugepages. - With vanilla 5.6.0-rc3 17.39user 1666.48system 27:37.89elapsed - With 5.6.0-rc3 + this patch, with proactiveness=20 8.35user 194.58system 3:19.62elapsed Elapsed time remains around 3:15, as proactiveness is further increased. Note that proactive compaction happens throughout the runtime of these workloads. The situation of one-time compaction, sufficient to supply hugepages for following allocation stream, can probably happen for more extreme proactiveness values, like 80 or 90. In the above Java workload, proactiveness is set to 20. The test starts with a node's score of 80 or higher, depending on the delay between the fragmentation step and starting the benchmark, which gives more-or-less time for the initial round of compaction. As t he benchmark consumes hugepages, node's score quickly rises above the high threshold (90) and proactive compaction starts again, which brings down the score to the low threshold level (80). Repeat. bpftrace also confirms proactive compaction running 20+ times during the runtime of this Java benchmark. kcompactd threads consume 100% of one of the CPUs while it tries to bring a node's score within thresholds. Backoff behavior ================ Above workloads produce a memory state which is easy to compact. However, if memory is filled with unmovable pages, proactive compaction should essentially back off. To test this aspect: - Created a kernel driver that allocates almost all memory as hugepages followed by freeing first 3/4 of each hugepage. - Set proactiveness=40 - Note that proactive_compact_node() is deferred maximum number of times with HPAGE_FRAG_CHECK_INTERVAL_MSEC of wait between each check (=> ~30 seconds between retries). [1] https://patchwork.kernel.org/patch/11098289/ [2] https://lore.kernel.org/linux-mm/[email protected]/ [3] https://lwn.net/Articles/817905/ Signed-off-by: Nitin Gupta <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Tested-by: Oleksandr Natalenko <[email protected]> Reviewed-by: Vlastimil Babka <[email protected]> Reviewed-by: Khalid Aziz <[email protected]> Reviewed-by: Oleksandr Natalenko <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: Khalid Aziz <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: David Rientjes <[email protected]> Cc: Nitin Gupta <[email protected]> Cc: Oleksandr Natalenko <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-08-12mm: memcg/percpu: per-memcg percpu memory statisticsRoman Gushchin1-0/+4
Percpu memory can represent a noticeable chunk of the total memory consumption, especially on big machines with many CPUs. Let's track percpu memory usage for each memcg and display it in memory.stat. A percpu allocation is usually scattered over multiple pages (and nodes), and can be significantly smaller than a page. So let's add a byte-sized counter on the memcg level: MEMCG_PERCPU_B. Byte-sized vmstat infra created for slabs can be perfectly reused for percpu case. [[email protected]: v3] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Roman Gushchin <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Reviewed-by: Shakeel Butt <[email protected]> Acked-by: Dennis Zhou <[email protected]> Acked-by: Johannes Weiner <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: David Rientjes <[email protected]> Cc: Joonsoo Kim <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: Tejun Heo <[email protected]> Cc: Tobin C. Harding <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: Waiman Long <[email protected]> Cc: Bixuan Cui <[email protected]> Cc: Michal Koutný <[email protected]> Cc: Stephen Rothwell <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-08-11Doc: admin-guide: use correct legends in kernel-parameters.txtRandy Dunlap1-18/+18
Documentation/admin-guide/kernel-parameters.rst includes a legend telling us what configurations or hardware platforms are relevant for certain boot options. For X86, it is spelled "X86" and for x86_64, it is spelled "X86-64", so make corrections for those. Signed-off-by: Randy Dunlap <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: [email protected] Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jonathan Corbet <[email protected]>
2020-08-11cpufreq: intel_pstate: Implement passive mode with HWP enabledRafael J. Wysocki1-46/+43
Allow intel_pstate to work in the passive mode with HWP enabled and make it set the HWP minimum performance limit (HWP floor) to the P-state value given by the target frequency supplied by the cpufreq governor, so as to prevent the HWP algorithm and the CPU scheduler from working against each other, at least when the schedutil governor is in use, and update the intel_pstate documentation accordingly. Among other things, this allows utilization clamps to be taken into account, at least to a certain extent, when intel_pstate is in use and makes it more likely that sufficient capacity for deadline tasks will be provided. After this change, the resulting behavior of an HWP system with intel_pstate in the passive mode should be close to the behavior of the analogous non-HWP system with intel_pstate in the passive mode, except that the HWP algorithm is generally allowed to make the CPU run at a frequency above the floor P-state set by intel_pstate in the entire available range of P-states, while without HWP a CPU can run in a P-state above the requested one if the latter falls into the range of turbo P-states (referred to as the turbo range) or if the P-states of all CPUs in one package are coordinated with each other at the hardware level. [Note that in principle the HWP floor may not be taken into account by the processor if it falls into the turbo range, in which case the processor has a license to choose any P-state, either below or above the HWP floor, just like a non-HWP processor in the case when the target P-state falls into the turbo range.] With this change applied, intel_pstate in the passive mode assumes complete control over the HWP request MSR and concurrent changes of that MSR (eg. via the direct MSR access interface) are overridden by it. Signed-off-by: Rafael J. Wysocki <[email protected]> Acked-by: Srinivas Pandruvada <[email protected]> Reviewed-by: Francisco Jerez <[email protected]>
2020-08-07Merge tag 'trace-v5.9' of ↵Linus Torvalds1-0/+11
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - The biggest news in that the tracing ring buffer can now time events that interrupted other ring buffer events. Before this change, if an interrupt came in while recording another event, and that interrupt also had an event, those events would all have the same time stamp as the event it interrupted. Now, with the new design, those events will have a unique time stamp and rightfully display the time for those events that were recorded while interrupting another event. - Bootconfig how has an "override" operator that lets the users have a default config, but then add options to override the default. - A fix was made to properly filter function graph tracing to the ftrace PIDs. This came in at the end of the -rc cycle, and needs to be backported. - Several clean ups, performance updates, and minor fixes as well. * tag 'trace-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (39 commits) tracing: Add trace_array_init_printk() to initialize instance trace_printk() buffers kprobes: Fix compiler warning for !CONFIG_KPROBES_ON_FTRACE tracing: Use trace_sched_process_free() instead of exit() for pid tracing bootconfig: Fix to find the initargs correctly Documentation: bootconfig: Add bootconfig override operator tools/bootconfig: Add testcases for value override operator lib/bootconfig: Add override operator support kprobes: Remove show_registers() function prototype tracing/uprobe: Remove dead code in trace_uprobe_register() kprobes: Fix NULL pointer dereference at kprobe_ftrace_handler ftrace: Fix ftrace_trace_task return value tracepoint: Use __used attribute definitions from compiler_attributes.h tracepoint: Mark __tracepoint_string's __used trace : Have tracing buffer info use kvzalloc instead of kzalloc tracing: Remove outdated comment in stack handling ftrace: Do not let direct or IPMODIFY ftrace_ops be added to module and set trampolines ftrace: Setup correct FTRACE_FL_REGS flags for module tracing/hwlat: Honor the tracing_cpumask tracing/hwlat: Drop the duplicate assignment in start_kthread() tracing: Save one trace_event->type by using __TRACE_LAST_TYPE ...
2020-08-07Merge tag 'for-5.9/dm-changes' of ↵Linus Torvalds2-7/+29
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - DM multipath locking fixes around m->flags tests and improvements to bio-based code so that it follows patterns established by request-based code. - Request-based DM core improvement to eliminate unnecessary call to blk_mq_queue_stopped(). - Add "panic_on_corruption" error handling mode to DM verity target. - DM bufio fix to to perform buffer cleanup from a workqueue rather than wait for IO in reclaim context from shrinker. - DM crypt improvement to optionally avoid async processing via workqueues for reads and/or writes -- via "no_read_workqueue" and "no_write_workqueue" features. This more direct IO processing improves latency and throughput with faster storage. Avoiding workqueue IO submission for writes (DM_CRYPT_NO_WRITE_WORKQUEUE) is a requirement for adding zoned block device support to DM crypt. - Add zoned block device support to DM crypt. Makes use of DM_CRYPT_NO_WRITE_WORKQUEUE and a new optional feature (DM_CRYPT_WRITE_INLINE) that allows write completion to wait for encryption to complete. This allows write ordering to be preserved, which is needed for zoned block devices. - Fix DM ebs target's check for REQ_OP_FLUSH. - Fix DM core's report zones support to not report more zones than were requested. - A few small compiler warning fixes. - DM dust improvements to return output directly to the user rather than require they scrape the system log for output. * tag 'for-5.9/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dm: don't call report zones for more than the user requested dm ebs: Fix incorrect checking for REQ_OP_FLUSH dm init: Set file local variable static dm ioctl: Fix compilation warning dm raid: Remove empty if statement dm verity: Fix compilation warning dm crypt: Enable zoned block device support dm crypt: add flags to optionally bypass kcryptd workqueues dm bufio: do buffer cleanup from a workqueue dm rq: don't call blk_mq_queue_stopped() in dm_stop_queue() dm dust: add interface to list all badblocks dm dust: report some message results directly back to user dm verity: add "panic_on_corruption" error handling mode dm mpath: use double checked locking in fast path dm mpath: rename current_pgpath to pgpath in multipath_prepare_ioctl dm mpath: rework __map_bio() dm mpath: factor out multipath_queue_bio dm mpath: push locking down to must_push_back_rq() dm mpath: take m->lock spinlock when testing QUEUE_IF_NO_PATH dm mpath: changes from initial m->flags locking audit