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2021-06-16media: docs: */media/index.rst: don't use ReST doc:`foo`Mauro Carvalho Chehab
The :doc:`foo` tag is auto-generated via automarkup.py. So, use the filename at the sources, instead of :doc:`foo`. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-06-14docs: cputopology: move the sysfs ABI description to right placeTian Tao
Documentation/admin-guide/cputopology.rst is the wrong place to describe sysfs ABI. So move the cputopology ABI things to Documentation/ABI/stable/sysfs-devices-system-cpu and add a reference to ABI doc in Documentation/admin-guide/cputopology.rst. Link: https://lkml.kernel.org/r/20210319041618.14316-1-song.bao.hua@hisilicon.com Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Tian Tao <tiantao6@hisilicon.com> Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Link: https://lore.kernel.org/r/20210611052249.25776-1-song.bao.hua@hisilicon.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-14Documentation: kdump: update kdump guideBaoquan He
Some parts of the guide are aged, hence need be updated. 1) The backup area of the 1st 640K on X86_64 has been removed by below commits, update the description accordingly. commit 7c321eb2b843 ("x86/kdump: Remove the backup region handling") commit 6f599d84231f ("x86/kdump: Always reserve the low 1M when the crashkernel option is specified") 2) Sort out the descripiton of "crashkernel syntax" part. 3) And some other minor cleanups. Signed-off-by: Baoquan He <bhe@redhat.com> Acked-by: Dave Young <dyoung@redhat.com> Link: https://lore.kernel.org/r/20210609083218.GB591017@MiWiFi-R3L-srv [jc: added blank line to fix added build warning] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-13docs: fix a cross-refKir Kolyshkin
Commit acda97acb2e98c9 changes dax.txt to dax.rst. Fix the references accordingly. Cc: Igor Matheus Andrade Torrente <igormtorrente@gmail.com> Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com> Link: https://lore.kernel.org/r/20210611030044.1982911-4-kolyshkin@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-06-11cpuidle: teo: Use kerneldoc documentation in admin-guideRafael J. Wysocki
There are two descriptions of the TEO (Timer Events Oriented) cpuidle governor in the kernel source tree, one in the C file containing its code and one in cpuidle.rst which is part of admin-guide. Instead of trying to keep them both in sync and in order to reduce text duplication, include the governor description from the C file directly into cpuidle.rst. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-06-10docs: bootconfig: Update for mixing value and subkeysMasami Hiramatsu
Update document for the mixing value and subkeys on a key. Link: https://lkml.kernel.org/r/162262196510.264090.15044943496205914148.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-10Documentation: Add usecases, design and interface for core schedulingJoel Fernandes (Google)
Now that core scheduling is merged, update the documentation. Co-developed-by: Chris Hyser <chris.hyser@oracle.com> Signed-off-by: Chris Hyser <chris.hyser@oracle.com> Co-developed-by: Josh Don <joshdon@google.com> Signed-off-by: Josh Don <joshdon@google.com> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210603013136.370918-1-joel@joelfernandes.org
2021-06-08cgroup: make per-cgroup pressure stall tracking configurableSuren Baghdasaryan
PSI accounts stalls for each cgroup separately and aggregates it at each level of the hierarchy. This causes additional overhead with psi_avgs_work being called for each cgroup in the hierarchy. psi_avgs_work has been highly optimized, however on systems with large number of cgroups the overhead becomes noticeable. Systems which use PSI only at the system level could avoid this overhead if PSI can be configured to skip per-cgroup stall accounting. Add "cgroup_disable=pressure" kernel command-line option to allow requesting system-wide only pressure stall accounting. When set, it keeps system-wide accounting under /proc/pressure/ but skips accounting for individual cgroups and does not expose PSI nodes in cgroup hierarchy. Signed-off-by: Suren Baghdasaryan <surenb@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-06-07x86/setup: Remove CONFIG_X86_RESERVE_LOW and reservelow= optionsMike Rapoport
The CONFIG_X86_RESERVE_LOW build time and reservelow= command line option allowed to control the amount of memory under 1M that would be reserved at boot to avoid using memory that can be potentially clobbered by BIOS. Since the entire range under 1M is always reserved there is no need for these options anymore and they can be removed. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20210601075354.5149-3-rppt@kernel.org
2021-06-04iommu/amd: Add amd_iommu=force_enable optionJoerg Roedel
Add this option to enable the IOMMU on platforms like AMD Stoney, where the kernel usually disables it because it may cause problems in some scenarios. Signed-off-by: Joerg Roedel <jroedel@suse.de> Acked-by: Alex Deucher <alexander.deucher@amd.com> Link: https://lore.kernel.org/r/20210603130203.29016-1-joro@8bytes.org
2021-06-03Merge branch 'sched/urgent' into sched/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-06-02docs: admin-guide: media: ipu3.rst: replace some charactersMauro Carvalho Chehab
The conversion tools used during DocBook/LaTeX/html/Markdown->ReST conversion and some cut-and-pasted text contain some characters that aren't easily reachable on standard keyboards and/or could cause troubles when parsed by the documentation build system. Replace the occurences of the following characters: - U+201c ('“'): LEFT DOUBLE QUOTATION MARK - U+201d ('”'): RIGHT DOUBLE QUOTATION MARK Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-06-02media: staging: ipu3-imgu: Move the UAPI header from include under include/uapiSakari Ailus
The header defines the user space interface but may be mistaken as kernel-only header due to its location. Add "uapi" directory under driver's include directory and move the header there. Suggested-by: Greg KH <gregkh@linuxfoundation.org> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Bingbu Cao <bingbu.cao@intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-06-01thunderbolt: Add support for retimer NVM upgrade when there is no linkRajmohan Mani
With help from platform firmware (ACPI) it is possible to power on retimers even when there is no USB4 link (e.g nothing is connected to the USB4 ports). This allows us to bring the USB4 sideband up so that we can access retimers and upgrade their NVM firmware. If the platform has support for this, we expose two additional attributes under USB4 ports: offline and rescan. These can be used to bring the port offline, rescan for the retimers and put the port online again. The retimer NVM upgrade itself works the same way than with cable connected. Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com> Co-developed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-31Merge 5.13-rc4 into tty-nextGreg Kroah-Hartman
We need the tty/serial fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-27docs: kernel-parameters: mark numa=off is supported by a bundle of architecturesBarry Song
risc-v and arm64 support numa=off by common arch_numa_init() in drivers/base/arch_numa.c. x86, ppc, mips, sparc support it by arch-level early_param. numa=off is widely used in linux distributions. it is better to document it. Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Link: https://lore.kernel.org/r/20210524051715.13604-1-song.bao.hua@hisilicon.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-26Merge tag 'net-5.13-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Networking fixes for 5.13-rc4, including fixes from bpf, netfilter, can and wireless trees. Notably including fixes for the recently announced "FragAttacks" WiFi vulnerabilities. Rather large batch, touching some core parts of the stack, too, but nothing hair-raising. Current release - regressions: - tipc: make node link identity publish thread safe - dsa: felix: re-enable TAS guard band mode - stmmac: correct clocks enabled in stmmac_vlan_rx_kill_vid() - stmmac: fix system hang if change mac address after interface ifdown Current release - new code bugs: - mptcp: avoid OOB access in setsockopt() - bpf: Fix nested bpf_bprintf_prepare with more per-cpu buffers - ethtool: stats: fix a copy-paste error - init correct array size Previous releases - regressions: - sched: fix packet stuck problem for lockless qdisc - net: really orphan skbs tied to closing sk - mlx4: fix EEPROM dump support - bpf: fix alu32 const subreg bound tracking on bitwise operations - bpf: fix mask direction swap upon off reg sign change - bpf, offload: reorder offload callback 'prepare' in verifier - stmmac: Fix MAC WoL not working if PHY does not support WoL - packetmmap: fix only tx timestamp on request - tipc: skb_linearize the head skb when reassembling msgs Previous releases - always broken: - mac80211: address recent "FragAttacks" vulnerabilities - mac80211: do not accept/forward invalid EAPOL frames - mptcp: avoid potential error message floods - bpf, ringbuf: deny reserve of buffers larger than ringbuf to prevent out of buffer writes - bpf: forbid trampoline attach for functions with variable arguments - bpf: add deny list of functions to prevent inf recursion of tracing programs - tls splice: check SPLICE_F_NONBLOCK instead of MSG_DONTWAIT - can: isotp: prevent race between isotp_bind() and isotp_setsockopt() - netfilter: nft_set_pipapo_avx2: Add irq_fpu_usable() check, fallback to non-AVX2 version Misc: - bpf: add kconfig knob for disabling unpriv bpf by default" * tag 'net-5.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (172 commits) net: phy: Document phydev::dev_flags bits allocation mptcp: validate 'id' when stopping the ADD_ADDR retransmit timer mptcp: avoid error message on infinite mapping mptcp: drop unconditional pr_warn on bad opt mptcp: avoid OOB access in setsockopt() nfp: update maintainer and mailing list addresses net: mvpp2: add buffer header handling in RX bnx2x: Fix missing error code in bnx2x_iov_init_one() net: zero-initialize tc skb extension on allocation net: hns: Fix kernel-doc sctp: fix the proc_handler for sysctl encap_port sctp: add the missing setting for asoc encap_port bpf, selftests: Adjust few selftest result_unpriv outcomes bpf: No need to simulate speculative domain for immediates bpf: Fix mask direction swap upon off reg sign change bpf: Wrap aux data inside bpf_sanitize_info container bpf: Fix BPF_LSM kconfig symbol dependency selftests/bpf: Add test for l3 use of bpf_redirect_peer bpftool: Add sock_release help info for cgroup attach/prog load command net: dsa: microchip: enable phy errata workaround on 9567 ...
2021-05-24Merge branch 'for-5.13-fixes' into for-5.14Tejun Heo
2021-05-24block_dump: remove comments in docszhangyi (F)
Now block_dump feature is gone, remove all comments in docs. Signed-off-by: zhangyi (F) <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210313030146.2882027-4-yi.zhang@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-21cpufreq: intel_pstate: hybrid: Avoid exposing two global attributesRafael J. Wysocki
The turbo_pct and num_pstates sysfs attributes represent CPU properties that may be different for differenty types of CPUs in a hybrid processor, so avoid exposing them in that case. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-05-20serial: liteuart: Add support for earlyconStafford Horne
Most litex boards using RISC-V soft cores us the sbi earlycon, however this is not available for non RISC-V litex SoC's. This patch enables earlycon for liteuart which is available on all Litex SoC's making support for earycon debugging more widely available. Cc: Florent Kermarrec <florent@enjoy-digital.fr> Cc: Mateusz Holenko <mholenko@antmicro.com> Cc: Joel Stanley <joel@jms.id.au> Cc: Gabriel L. Somlo <gsomlo@gmail.com> Reviewed-and-tested-by: Gabriel Somlo <gsomlo@gmail.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Reviewed-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Stafford Horne <shorne@gmail.com> Link: https://lore.kernel.org/r/20210517115453.24365-1-shorne@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-18Merge branches 'bitmaprange.2021.05.10c', 'doc.2021.05.10c', ↵Paul E. McKenney
'fixes.2021.05.13a', 'kvfree_rcu.2021.05.10c', 'mmdumpobj.2021.05.10c', 'nocb.2021.05.12a', 'srcu.2021.05.12a', 'tasks.2021.05.18a' and 'torture.2021.05.10c' into HEAD bitmaprange.2021.05.10c: Allow "all" for bitmap ranges. doc.2021.05.10c: Documentation updates. fixes.2021.05.13a: Miscellaneous fixes. kvfree_rcu.2021.05.10c: kvfree_rcu() updates. mmdumpobj.2021.05.10c: mem_dump_obj() updates. nocb.2021.05.12a: RCU NOCB CPU updates, including limited deoffloading. srcu.2021.05.12a: SRCU updates. tasks.2021.05.18a: Tasks-RCU updates. torture.2021.05.10c: Torture-test updates.
2021-05-18Documentation/admin-guide: Add bus lock ratelimitFenghua Yu
Since bus lock rate limit changes the split_lock_detect parameter, update the documentation for the change. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/r/20210419214958.4035512-4-fenghua.yu@intel.com
2021-05-18delayacct: Document task_delayacct sysctlMel Gorman
Update sysctl/kernel.rst. Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210512114035.GH3672@suse.de
2021-05-14docs: admin-guide: update description for kernel.modprobe sysctlRasmus Villemoes
When I added CONFIG_MODPROBE_PATH, I neglected to update Documentation/. It's still true that this defaults to /sbin/modprobe, but now via a level of indirection. So document that the kernel might have been built with something other than /sbin/modprobe as the initial value. Link: https://lkml.kernel.org/r/20210420125324.1246826-1-linux@rasmusvillemoes.dk Fixes: 17652f4240f7a ("modules: add CONFIG_MODPROBE_PATH") Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-13docs: admin-guide: update description for kernel.hotplug sysctlRasmus Villemoes
It's been a few releases since this defaulted to /sbin/hotplug. Update the text, and include pointers to the two CONFIG_UEVENT_HELPER{,_PATH} config knobs whose help text could provide more info, but also hint that the user probably doesn't need to care at all. Fixes: 7934779a69f1 ("Driver-Core: disable /sbin/hotplug by default") Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Link: https://lore.kernel.org/r/20210420120638.1104016-1-linux@rasmusvillemoes.dk Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-12delayacct: Default disabledPeter Zijlstra
Assuming this stuff isn't actually used much; disable it by default and avoid allocating and tracking the task_delay_info structure. taskstats is changed to still report the regular sched and sched_info and only skip the missing task_delay_info fields instead of not reporting anything. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20210505111525.308018373@infradead.org
2021-05-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf 2021-05-11 The following pull-request contains BPF updates for your *net* tree. We've added 13 non-merge commits during the last 8 day(s) which contain a total of 21 files changed, 817 insertions(+), 382 deletions(-). The main changes are: 1) Fix multiple ringbuf bugs in particular to prevent writable mmap of read-only pages, from Andrii Nakryiko & Thadeu Lima de Souza Cascardo. 2) Fix verifier alu32 known-const subregister bound tracking for bitwise operations and/or/xor, from Daniel Borkmann. 3) Reject trampoline attachment for functions with variable arguments, and also add a deny list of other forbidden functions, from Jiri Olsa. 4) Fix nested bpf_bprintf_prepare() calls used by various helpers by switching to per-CPU buffers, from Florent Revest. 5) Fix kernel compilation with BTF debug info on ppc64 due to pahole missing TCP-CC functions like cubictcp_init, from Martin KaFai Lau. 6) Add a kconfig entry to provide an option to disallow unprivileged BPF by default, from Daniel Borkmann. 7) Fix libbpf compilation for older libelf when GELF_ST_VISIBILITY() macro is not available, from Arnaldo Carvalho de Melo. 8) Migrate test_tc_redirect to test_progs framework as prep work for upcoming skb_change_head() fix & selftest, from Jussi Maki. 9) Fix a libbpf segfault in add_dummy_ksym_var() if BTF is not present, from Ian Rogers. 10) Fix tx_only micro-benchmark in xdpsock BPF sample with proper frame size, from Magnus Karlsson. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-11bpf: Add kconfig knob for disabling unpriv bpf by defaultDaniel Borkmann
Add a kconfig knob which allows for unprivileged bpf to be disabled by default. If set, the knob sets /proc/sys/kernel/unprivileged_bpf_disabled to value of 2. This still allows a transition of 2 -> {0,1} through an admin. Similarly, this also still keeps 1 -> {1} behavior intact, so that once set to permanently disabled, it cannot be undone aside from a reboot. We've also added extra2 with max of 2 for the procfs handler, so that an admin still has a chance to toggle between 0 <-> 2. Either way, as an additional alternative, applications can make use of CAP_BPF that we added a while ago. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/74ec548079189e4e4dffaeb42b8987bb3c852eee.1620765074.git.daniel@iogearbox.net
2021-05-10kvfree_rcu: Release a page cache under memory pressureZhang Qiang
Add a drain_page_cache() function to drain a per-cpu page cache. The reason behind of it is a system can run into a low memory condition, in that case a page shrinker can ask for its users to free their caches in order to get extra memory available for other needs in a system. When a system hits such condition, a page cache is drained for all CPUs in a system. By default a page cache work is delayed with 5 seconds interval until a memory pressure disappears, if needed it can be changed. See a rcu_delay_page_cache_fill_msec module parameter. Co-developed-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Signed-off-by: Zqiang <qiang.zhang@windriver.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10bitmap_parse: Support 'all' semanticsYury Norov
RCU code supports an 'all' group as a special case when parsing rcu_nocbs parameter. This patch moves the 'all' support to the core bitmap_parse code, so that all bitmap users can enjoy this extension. Moving 'all' parsing to a bitmap_parse level also allows users to pass patterns together with 'all' in regular group:pattern format, for example, "rcu_nocbs=all:1/2" would offload all the even-numbered CPUs regardless of the number of CPUs on the system. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10docs/cgroup: add entry for cgroup.killChristian Brauner
Give a brief overview of the cgroup.kill functionality. Link: https://lore.kernel.org/r/20210503143922.3093755-2-brauner@kernel.org Cc: Roman Gushchin <guro@fb.com> Cc: Tejun Heo <tj@kernel.org> Cc: cgroups@vger.kernel.org Reviewed-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-05-08Merge branch 'master' into nextMichael Ellerman
Merge master back into next, this allows us to resolve some conflicts in arch/powerpc/Kconfig, and also re-sort the symbols under config PPC so that they are in alphabetical order again.
2021-05-07Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge yet more updates from Andrew Morton: "This is everything else from -mm for this merge window. 90 patches. Subsystems affected by this patch series: mm (cleanups and slub), alpha, procfs, sysctl, misc, core-kernel, bitmap, lib, compat, checkpatch, epoll, isofs, nilfs2, hpfs, exit, fork, kexec, gcov, panic, delayacct, gdb, resource, selftests, async, initramfs, ipc, drivers/char, and spelling" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (90 commits) mm: fix typos in comments mm: fix typos in comments treewide: remove editor modelines and cruft ipc/sem.c: spelling fix fs: fat: fix spelling typo of values kernel/sys.c: fix typo kernel/up.c: fix typo kernel/user_namespace.c: fix typos kernel/umh.c: fix some spelling mistakes include/linux/pgtable.h: few spelling fixes mm/slab.c: fix spelling mistake "disired" -> "desired" scripts/spelling.txt: add "overflw" scripts/spelling.txt: Add "diabled" typo scripts/spelling.txt: add "overlfow" arm: print alloc free paths for address in registers mm/vmalloc: remove vwrite() mm: remove xlate_dev_kmem_ptr() drivers/char: remove /dev/kmem for good mm: fix some typos and code style problems ipc/sem.c: mundane typo fixes ...
2021-05-07drivers/char: remove /dev/kmem for goodDavid Hildenbrand
Patch series "drivers/char: remove /dev/kmem for good". Exploring /dev/kmem and /dev/mem in the context of memory hot(un)plug and memory ballooning, I started questioning the existence of /dev/kmem. Comparing it with the /proc/kcore implementation, it does not seem to be able to deal with things like a) Pages unmapped from the direct mapping (e.g., to be used by secretmem) -> kern_addr_valid(). virt_addr_valid() is not sufficient. b) Special cases like gart aperture memory that is not to be touched -> mem_pfn_is_ram() Unless I am missing something, it's at least broken in some cases and might fault/crash the machine. Looks like its existence has been questioned before in 2005 and 2010 [1], after ~11 additional years, it might make sense to revive the discussion. CONFIG_DEVKMEM is only enabled in a single defconfig (on purpose or by mistake?). All distributions disable it: in Ubuntu it has been disabled for more than 10 years, in Debian since 2.6.31, in Fedora at least starting with FC3, in RHEL starting with RHEL4, in SUSE starting from 15sp2, and OpenSUSE has it disabled as well. 1) /dev/kmem was popular for rootkits [2] before it got disabled basically everywhere. Ubuntu documents [3] "There is no modern user of /dev/kmem any more beyond attackers using it to load kernel rootkits.". RHEL documents in a BZ [5] "it served no practical purpose other than to serve as a potential security problem or to enable binary module drivers to access structures/functions they shouldn't be touching" 2) /proc/kcore is a decent interface to have a controlled way to read kernel memory for debugging puposes. (will need some extensions to deal with memory offlining/unplug, memory ballooning, and poisoned pages, though) 3) It might be useful for corner case debugging [1]. KDB/KGDB might be a better fit, especially, to write random memory; harder to shoot yourself into the foot. 4) "Kernel Memory Editor" [4] hasn't seen any updates since 2000 and seems to be incompatible with 64bit [1]. For educational purposes, /proc/kcore might be used to monitor value updates -- or older kernels can be used. 5) It's broken on arm64, and therefore, completely disabled there. Looks like it's essentially unused and has been replaced by better suited interfaces for individual tasks (/proc/kcore, KDB/KGDB). Let's just remove it. [1] https://lwn.net/Articles/147901/ [2] https://www.linuxjournal.com/article/10505 [3] https://wiki.ubuntu.com/Security/Features#A.2Fdev.2Fkmem_disabled [4] https://sourceforge.net/projects/kme/ [5] https://bugzilla.redhat.com/show_bug.cgi?id=154796 Link: https://lkml.kernel.org/r/20210324102351.6932-1-david@redhat.com Link: https://lkml.kernel.org/r/20210324102351.6932-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Alexander A. Klimov" <grandmaster@al2klimov.de> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Brian Cain <bcain@codeaurora.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Chris Zankel <chris@zankel.net> Cc: Corentin Labbe <clabbe@baylibre.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Greentime Hu <green.hu@gmail.com> Cc: Gregory Clement <gregory.clement@bootlin.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Hillf Danton <hdanton@sina.com> Cc: huang ying <huang.ying.caritas@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: James Troup <james.troup@canonical.com> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kairui Song <kasong@redhat.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mike Rapoport <rppt@kernel.org> Cc: Mikulas Patocka <mpatocka@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Niklas Schnelle <schnelle@linux.ibm.com> Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com> Cc: openrisc@lists.librecores.org Cc: Palmer Dabbelt <palmerdabbelt@google.com> Cc: Paul Mackerras <paulus@samba.org> Cc: "Pavel Machek (CIP)" <pavel@denx.de> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Pierre Morel <pmorel@linux.ibm.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Rich Felker <dalias@libc.org> Cc: Robert Richter <rric@kernel.org> Cc: Rob Herring <robh@kernel.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> Cc: sparclinux@vger.kernel.org Cc: Stafford Horne <shorne@gmail.com> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Theodore Dubois <tblodt@icloud.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: William Cohen <wcohen@redhat.com> Cc: Xiaoming Ni <nixiaoming@huawei.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07init/initramfs.c: do unpacking asynchronouslyRasmus Villemoes
Patch series "background initramfs unpacking, and CONFIG_MODPROBE_PATH", v3. These two patches are independent, but better-together. The second is a rather trivial patch that simply allows the developer to change "/sbin/modprobe" to something else - e.g. the empty string, so that all request_module() during early boot return -ENOENT early, without even spawning a usermode helper, needlessly synchronizing with the initramfs unpacking. The first patch delegates decompressing the initramfs to a worker thread, allowing do_initcalls() in main.c to proceed to the device_ and late_ initcalls without waiting for that decompression (and populating of rootfs) to finish. Obviously, some of those later calls may rely on the initramfs being available, so I've added synchronization points in the firmware loader and usermodehelper paths - there might be other places that would need this, but so far no one has been able to think of any places I have missed. There's not much to win if most of the functionality needed during boot is only available as modules. But systems with a custom-made .config and initramfs can boot faster, partly due to utilizing more than one cpu earlier, partly by avoiding known-futile modprobe calls (which would still trigger synchronization with the initramfs unpacking, thus eliminating most of the first benefit). This patch (of 2): Most of the boot process doesn't actually need anything from the initramfs, until of course PID1 is to be executed. So instead of doing the decompressing and populating of the initramfs synchronously in populate_rootfs() itself, push that off to a worker thread. This is primarily motivated by an embedded ppc target, where unpacking even the rather modest sized initramfs takes 0.6 seconds, which is long enough that the external watchdog becomes unhappy that it doesn't get attention soon enough. By doing the initramfs decompression in a worker thread, we get to do the device_initcalls and hence start petting the watchdog much sooner. Normal desktops might benefit as well. On my mostly stock Ubuntu kernel, my initramfs is a 26M xz-compressed blob, decompressing to around 126M. That takes almost two seconds: [ 0.201454] Trying to unpack rootfs image as initramfs... [ 1.976633] Freeing initrd memory: 29416K Before this patch, these lines occur consecutively in dmesg. With this patch, the timestamps on these two lines is roughly the same as above, but with 172 lines inbetween - so more than one cpu has been kept busy doing work that would otherwise only happen after the populate_rootfs() finished. Should one of the initcalls done after rootfs_initcall time (i.e., device_ and late_ initcalls) need something from the initramfs (say, a kernel module or a firmware blob), it will simply wait for the initramfs unpacking to be done before proceeding, which should in theory make this completely safe. But if some driver pokes around in the filesystem directly and not via one of the official kernel interfaces (i.e. request_firmware*(), call_usermodehelper*) that theory may not hold - also, I certainly might have missed a spot when sprinkling wait_for_initramfs(). So there is an escape hatch in the form of an initramfs_async= command line parameter. Link: https://lkml.kernel.org/r/20210313212528.2956377-1-linux@rasmusvillemoes.dk Link: https://lkml.kernel.org/r/20210313212528.2956377-2-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06Merge tag 'riscv-for-linus-5.13-mw0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for the memtest= kernel command-line argument. - Support for building the kernel with FORTIFY_SOURCE. - Support for generic clockevent broadcasts. - Support for the buildtar build target. - Some build system cleanups to pass more LLVM-friendly arguments. - Support for kprobes. - A rearranged kernel memory map, the first part of supporting sv48 systems. - Improvements to kexec, along with support for kdump and crash kernels. - An alternatives-based errata framework, along with support for handling a pair of errata that manifest on some SiFive designs (including the HiFive Unmatched). - Support for XIP. - A device tree for the Microchip PolarFire ICICLE SoC and associated dev board. ... along with a bunch of cleanups. There are already a handful of fixes on the list so there will likely be a part 2. * tag 'riscv-for-linus-5.13-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (45 commits) RISC-V: Always define XIP_FIXUP riscv: Remove 32b kernel mapping from page table dump riscv: Fix 32b kernel build with CONFIG_DEBUG_VIRTUAL=y RISC-V: Fix error code returned by riscv_hartid_to_cpuid() RISC-V: Enable Microchip PolarFire ICICLE SoC RISC-V: Initial DTS for Microchip ICICLE board dt-bindings: riscv: microchip: Add YAML documentation for the PolarFire SoC RISC-V: Add Microchip PolarFire SoC kconfig option RISC-V: enable XIP RISC-V: Add crash kernel support RISC-V: Add kdump support RISC-V: Improve init_resources() RISC-V: Add kexec support RISC-V: Add EM_RISCV to kexec UAPI header riscv: vdso: fix and clean-up Makefile riscv/mm: Use BUG_ON instead of if condition followed by BUG. riscv/kprobe: fix kernel panic when invoking sys_read traced by kprobe riscv: Set ARCH_HAS_STRICT_MODULE_RWX if MMU riscv: module: Create module allocations without exec permissions riscv: bpf: Avoid breaking W^X ...
2021-05-06Merge tag 'docs-5.13-2' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation fixes from Jonathan Corbet: "A few late-arriving documentation fixes, including some oprofile cleanup, a kernel-doc fix, some regression-reporting updates, and the usual minor fixes" * tag 'docs-5.13-2' of git://git.lwn.net/linux: Enlisted oprofile version line removed oprofiled version output line removed from the list Removed the oprofiled version option docs: reporting-issues.rst: CC subsystem and maintainers on regressions docs: correct URL to bios and kernel developer's guide docs/core-api: Consistent code style docs/zh_CN: Adjust order and content of zh_CN/index.rst Documentation: input: joydev file corrections docs: Fix typo in Documentation/x86/x86_64/5level-paging.rst kernel-doc: Add support for __deprecated
2021-05-05Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge more updates from Andrew Morton: "The remainder of the main mm/ queue. 143 patches. Subsystems affected by this patch series (all mm): pagecache, hugetlb, userfaultfd, vmscan, compaction, migration, cma, ksm, vmstat, mmap, kconfig, util, memory-hotplug, zswap, zsmalloc, highmem, cleanups, and kfence" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (143 commits) kfence: use power-efficient work queue to run delayed work kfence: maximize allocation wait timeout duration kfence: await for allocation using wait_event kfence: zero guard page after out-of-bounds access mm/process_vm_access.c: remove duplicate include mm/mempool: minor coding style tweaks mm/highmem.c: fix coding style issue btrfs: use memzero_page() instead of open coded kmap pattern iov_iter: lift memzero_page() to highmem.h mm/zsmalloc: use BUG_ON instead of if condition followed by BUG. mm/zswap.c: switch from strlcpy to strscpy arm64/Kconfig: introduce ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE x86/Kconfig: introduce ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE mm,memory_hotplug: add kernel boot option to enable memmap_on_memory acpi,memhotplug: enable MHP_MEMMAP_ON_MEMORY when supported mm,memory_hotplug: allocate memmap from the added memory range mm,memory_hotplug: factor out adjusting present pages into adjust_present_page_count() mm,memory_hotplug: relax fully spanned sections check drivers/base/memory: introduce memory_block_{online,offline} mm/memory_hotplug: remove broken locking of zone PCP structures during hot remove ...
2021-05-05Merge tag 'gpio-updates-for-v5.13-v2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux Pull gpio updates from Bartosz Golaszewski: - new driver for the Realtek Otto GPIO controller - ACPI support for gpio-mpc8xxx - edge event support for gpio-sch (+ Kconfig fixes) - Kconfig improvements in gpio-ich - fixes to older issues in gpio-mockup - ACPI quirk for ignoring EC wakeups on Dell Venue 10 Pro 5055 - improve the GPIO aggregator code by using more generic interfaces instead of reimplementing them in the driver - convert the DT bindings for gpio-74x164 to yaml - documentation improvements - a slew of other minor fixes and improvements to GPIO drivers * tag 'gpio-updates-for-v5.13-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (34 commits) dt-bindings: gpio: add YAML description for rockchip,gpio-bank gpio: mxs: remove useless function dt-bindings: gpio: fairchild,74hc595: Convert to json-schema gpio: it87: remove unused code gpio: 104-dio-48e: Fix coding style issues gpio: mpc8xxx: Add ACPI support gpio: ich: Switch to be dependent on LPC_ICH gpio: sch: Drop MFD_CORE selection gpio: sch: depends on LPC_SCH gpiolib: acpi: Add quirk to ignore EC wakeups on Dell Venue 10 Pro 5055 gpio: sch: Hook into ACPI GPE handler to catch GPIO edge events gpio: sch: Add edge event support gpio: aggregator: Replace custom get_arg() with a generic next_arg() lib/cmdline: Export next_arg() for being used in modules gpio: omap: Use device_get_match_data() helper gpio: Add Realtek Otto GPIO support dt-bindings: gpio: Binding for Realtek Otto GPIO docs: kernel-parameters: Add gpio_mockup_named_lines docs: kernel-parameters: Move gpio-mockup for alphabetic order lib: bitmap: provide devm_bitmap_alloc() and devm_bitmap_zalloc() ...
2021-05-05mm,memory_hotplug: add kernel boot option to enable memmap_on_memoryOscar Salvador
Self stored memmap leads to a sparse memory situation which is unsuitable for workloads that requires large contiguous memory chunks, so make this an opt-in which needs to be explicitly enabled. To control this, let memory_hotplug have its own memory space, as suggested by David, so we can add memory_hotplug.memmap_on_memory parameter. Link: https://lkml.kernel.org/r/20210421102701.25051-7-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05memory-hotplug.rst: add a note about ZONE_MOVABLE and page pinningPavel Tatashin
Document the special handling of page pinning when ZONE_MOVABLE present. Link: https://lkml.kernel.org/r/20210215161349.246722-11-pasha.tatashin@soleen.com Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> Suggested-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: James Morris <jmorris@namei.org> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sasha Levin <sashal@kernel.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Tyler Hicks <tyhicks@linux.microsoft.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05userfaultfd: update documentation to describe minor fault handlingAxel Rasmussen
Reword / reorganize things a little bit into "lists", so new features / modes / ioctls can sort of just be appended. Describe how UFFDIO_REGISTER_MODE_MINOR and UFFDIO_CONTINUE can be used to intercept and resolve minor faults. Make it clear that COPY and ZEROPAGE are used for MISSING faults, whereas CONTINUE is used for MINOR faults. Link: https://lkml.kernel.org/r/20210301222728.176417-6-axelrasmussen@google.com Signed-off-by: Axel Rasmussen <axelrasmussen@google.com> Reviewed-by: Peter Xu <peterx@redhat.com> Cc: Adam Ruprecht <ruprecht@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Cannon Matthews <cannonmatthews@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chinwen Chang <chinwen.chang@mediatek.com> Cc: David Rientjes <rientjes@google.com> Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Lokesh Gidra <lokeshgidra@google.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michal Koutn" <mkoutny@suse.com> Cc: Michel Lespinasse <walken@google.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Mina Almasry <almasrymina@google.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oliver Upton <oupton@google.com> Cc: Shaohua Li <shli@fb.com> Cc: Shawn Anastasio <shawn@anastas.io> Cc: Steven Price <steven.price@arm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05docs: kernel-parameters: Add gpio_mockup_named_linesAlexander Dahl
Missing since introduced in the driver. Fixes: 8a68ea00a62e ("gpio: mockup: implement naming the lines") Signed-off-by: Alexander Dahl <ada@thorsis.com> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2021-05-05docs: kernel-parameters: Move gpio-mockup for alphabetic orderAlexander Dahl
All other sections are ordered alphabetically so do the same for gpio-mockup. Fixes: 0f98dd1b27d2 ("gpio/mockup: add virtual gpio device") Signed-off-by: Alexander Dahl <ada@thorsis.com> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2021-05-04powerpc/64s/radix: Enable huge vmalloc mappingsNicholas Piggin
This reduces TLB misses by nearly 30x on a `git diff` workload on a 2-node POWER9 (59,800 -> 2,100) and reduces CPU cycles by 0.54%, due to vfs hashes being allocated with 2MB pages. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210503091755.613393-1-npiggin@gmail.com
2021-05-03docs: reporting-issues.rst: CC subsystem and maintainers on regressionsThorsten Leemhuis
When reporting a regression, users ideally should CC the subsystem and its maintainers, as that will ensure they get aware of the regression quickly. And if the culprit is known, they should also CC everyone who signed if off; the text mentioned the latter in once place already, but forgot to do so in two other areas where it's relevant. While fixing this also remind readers to check the mailing list archives for issues that need to be reported to a bug tracker, as someone might have reported it by mail only. All of this got triggered by a recent report where these changes would have made a difference. Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info> Link: https://lore.kernel.org/lkml/dff6badf-58f5-98c8-871c-94d901ac6919@leemhuis.info/ Link: https://lore.kernel.org/lkml/CAJZ5v0hX2StQVttAciHYH-urUH+Hi92z9z2ZbcNgQPt0E2Jpwg@mail.gmail.com/ Link: https://lore.kernel.org/r/dd13f10c30e79e550215e53a8103406daec4e593.1618482489.git.linux@leemhuis.info Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-01Merge tag 'iommu-updates-v5.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull iommu updates from Joerg Roedel: - Big cleanup of almost unsused parts of the IOMMU API by Christoph Hellwig. This mostly affects the Freescale PAMU driver. - New IOMMU driver for Unisoc SOCs - ARM SMMU Updates from Will: - Drop vestigial PREFETCH_ADDR support (SMMUv3) - Elide TLB sync logic for empty gather (SMMUv3) - Fix "Service Failure Mode" handling (SMMUv3) - New Qualcomm compatible string (SMMUv2) - Removal of the AMD IOMMU performance counter writeable check on AMD. It caused long boot delays on some machines and is only needed to work around an errata on some older (possibly pre-production) chips. If someone is still hit by this hardware issue anyway the performance counters will just return 0. - Support for targeted invalidations in the AMD IOMMU driver. Before that the driver only invalidated a single 4k page or the whole IO/TLB for an address space. This has been extended now and is mostly useful for emulated AMD IOMMUs. - Several fixes for the Shared Virtual Memory support in the Intel VT-d driver - Mediatek drivers can now be built as modules - Re-introduction of the forcedac boot option which got lost when converting the Intel VT-d driver to the common dma-iommu implementation. - Extension of the IOMMU device registration interface and support iommu_ops to be const again when drivers are built as modules. * tag 'iommu-updates-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (84 commits) iommu: Streamline registration interface iommu: Statically set module owner iommu/mediatek-v1: Add error handle for mtk_iommu_probe iommu/mediatek-v1: Avoid build fail when build as module iommu/mediatek: Always enable the clk on resume iommu/fsl-pamu: Fix uninitialized variable warning iommu/vt-d: Force to flush iotlb before creating superpage iommu/amd: Put newline after closing bracket in warning iommu/vt-d: Fix an error handling path in 'intel_prepare_irq_remapping()' iommu/vt-d: Fix build error of pasid_enable_wpe() with !X86 iommu/amd: Remove performance counter pre-initialization test Revert "iommu/amd: Fix performance counter initialization" iommu/amd: Remove duplicate check of devid iommu/exynos: Remove unneeded local variable initialization iommu/amd: Page-specific invalidations for more than one page iommu/arm-smmu-v3: Remove the unused fields for PREFETCH_CONFIG command iommu/vt-d: Avoid unnecessary cache flush in pasid entry teardown iommu/vt-d: Invalidate PASID cache when root/context entry changed iommu/vt-d: Remove WO permissions on second-level paging entries iommu/vt-d: Report the right page fault address ...
2021-04-30Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc updates from Andrew Morton: "A few misc subsystems and some of MM. 175 patches. Subsystems affected by this patch series: ia64, kbuild, scripts, sh, ocfs2, kfifo, vfs, kernel/watchdog, and mm (slab-generic, slub, kmemleak, debug, pagecache, msync, gup, memremap, memcg, pagemap, mremap, dma, sparsemem, vmalloc, documentation, kasan, initialization, pagealloc, and memory-failure)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (175 commits) mm/memory-failure: unnecessary amount of unmapping mm/mmzone.h: fix existing kernel-doc comments and link them to core-api mm: page_alloc: ignore init_on_free=1 for debug_pagealloc=1 net: page_pool: use alloc_pages_bulk in refill code path net: page_pool: refactor dma_map into own function page_pool_dma_map SUNRPC: refresh rq_pages using a bulk page allocator SUNRPC: set rq_page_end differently mm/page_alloc: inline __rmqueue_pcplist mm/page_alloc: optimize code layout for __alloc_pages_bulk mm/page_alloc: add an array-based interface to the bulk page allocator mm/page_alloc: add a bulk page allocator mm/page_alloc: rename alloced to allocated mm/page_alloc: duplicate include linux/vmalloc.h mm, page_alloc: avoid page_to_pfn() in move_freepages() mm/Kconfig: remove default DISCONTIGMEM_MANUAL mm: page_alloc: dump migrate-failed pages mm/mempolicy: fix mpol_misplaced kernel-doc mm/mempolicy: rewrite alloc_pages_vma documentation mm/mempolicy: rewrite alloc_pages documentation mm/mempolicy: rename alloc_pages_current to alloc_pages ...
2021-04-30Merge tag 'powerpc-5.13-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Enable KFENCE for 32-bit. - Implement EBPF for 32-bit. - Convert 32-bit to do interrupt entry/exit in C. - Convert 64-bit BookE to do interrupt entry/exit in C. - Changes to our signal handling code to use user_access_begin/end() more extensively. - Add support for time namespaces (CONFIG_TIME_NS) - A series of fixes that allow us to reenable STRICT_KERNEL_RWX. - Other smaller features, fixes & cleanups. Thanks to Alexey Kardashevskiy, Andreas Schwab, Andrew Donnellan, Aneesh Kumar K.V, Athira Rajeev, Bhaskar Chowdhury, Bixuan Cui, Cédric Le Goater, Chen Huang, Chris Packham, Christophe Leroy, Christopher M. Riedl, Colin Ian King, Dan Carpenter, Daniel Axtens, Daniel Henrique Barboza, David Gibson, Davidlohr Bueso, Denis Efremov, dingsenjie, Dmitry Safonov, Dominic DeMarco, Fabiano Rosas, Ganesh Goudar, Geert Uytterhoeven, Geetika Moolchandani, Greg Kurz, Guenter Roeck, Haren Myneni, He Ying, Jiapeng Chong, Jordan Niethe, Laurent Dufour, Lee Jones, Leonardo Bras, Li Huafei, Madhavan Srinivasan, Mahesh Salgaonkar, Masahiro Yamada, Nathan Chancellor, Nathan Lynch, Nicholas Piggin, Oliver O'Halloran, Paul Menzel, Pu Lehui, Randy Dunlap, Ravi Bangoria, Rosen Penev, Russell Currey, Santosh Sivaraj, Sebastian Andrzej Siewior, Segher Boessenkool, Shivaprasad G Bhat, Srikar Dronamraju, Stephen Rothwell, Thadeu Lima de Souza Cascardo, Thomas Gleixner, Tony Ambardar, Tyrel Datwyler, Vaibhav Jain, Vincenzo Frascino, Xiongwei Song, Yang Li, Yu Kuai, and Zhang Yunkai. * tag 'powerpc-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (302 commits) powerpc/signal32: Fix erroneous SIGSEGV on RT signal return powerpc: Avoid clang uninitialized warning in __get_user_size_allowed powerpc/papr_scm: Mark nvdimm as unarmed if needed during probe powerpc/kvm: Fix build error when PPC_MEM_KEYS/PPC_PSERIES=n powerpc/kasan: Fix shadow start address with modules powerpc/kernel/iommu: Use largepool as a last resort when !largealloc powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs powerpc/44x: fix spelling mistake in Kconfig "varients" -> "variants" powerpc/iommu: Annotate nested lock for lockdep powerpc/iommu: Do not immediately panic when failed IOMMU table allocation powerpc/iommu: Allocate it_map by vmalloc selftests/powerpc: remove unneeded semicolon powerpc/64s: remove unneeded semicolon powerpc/eeh: remove unneeded semicolon powerpc/selftests: Add selftest to test concurrent perf/ptrace events powerpc/selftests/perf-hwbreak: Add testcases for 2nd DAWR powerpc/selftests/perf-hwbreak: Coalesce event creation code powerpc/selftests/ptrace-hwbreak: Add testcases for 2nd DAWR powerpc/configs: Add IBMVNIC to some 64-bit configs selftests/powerpc: Add uaccess flush test ...