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2021-05-12ptrace: make ptrace() fail if the tracee changed its pid unexpectedlyOleg Nesterov
Suppose we have 2 threads, the group-leader L and a sub-theread T, both parked in ptrace_stop(). Debugger tries to resume both threads and does ptrace(PTRACE_CONT, T); ptrace(PTRACE_CONT, L); If the sub-thread T execs in between, the 2nd PTRACE_CONT doesn not resume the old leader L, it resumes the post-exec thread T which was actually now stopped in PTHREAD_EVENT_EXEC. In this case the PTHREAD_EVENT_EXEC event is lost, and the tracer can't know that the tracee changed its pid. This patch makes ptrace() fail in this case until debugger does wait() and consumes PTHREAD_EVENT_EXEC which reports old_pid. This affects all ptrace requests except the "asynchronous" PTRACE_INTERRUPT/KILL. The patch doesn't add the new PTRACE_ option to not complicate the API, and I _hope_ this won't cause any noticeable regression: - If debugger uses PTRACE_O_TRACEEXEC and the thread did an exec and the tracer does a ptrace request without having consumed the exec event, it's 100% sure that the thread the ptracer thinks it is targeting does not exist anymore, or isn't the same as the one it thinks it is targeting. - To some degree this patch adds nothing new. In the scenario above ptrace(L) can fail with -ESRCH if it is called after the execing sub-thread wakes the leader up and before it "steals" the leader's pid. Test-case: #include <stdio.h> #include <unistd.h> #include <signal.h> #include <sys/ptrace.h> #include <sys/wait.h> #include <errno.h> #include <pthread.h> #include <assert.h> void *tf(void *arg) { execve("/usr/bin/true", NULL, NULL); assert(0); return NULL; } int main(void) { int leader = fork(); if (!leader) { kill(getpid(), SIGSTOP); pthread_t th; pthread_create(&th, NULL, tf, NULL); for (;;) pause(); return 0; } waitpid(leader, NULL, WSTOPPED); ptrace(PTRACE_SEIZE, leader, 0, PTRACE_O_TRACECLONE | PTRACE_O_TRACEEXEC); waitpid(leader, NULL, 0); ptrace(PTRACE_CONT, leader, 0,0); waitpid(leader, NULL, 0); int status, thread = waitpid(-1, &status, 0); assert(thread > 0 && thread != leader); assert(status == 0x80137f); ptrace(PTRACE_CONT, thread, 0,0); /* * waitid() because waitpid(leader, &status, WNOWAIT) does not * report status. Why ???? * * Why WEXITED? because we have another kernel problem connected * to mt-exec. */ siginfo_t info; assert(waitid(P_PID, leader, &info, WSTOPPED|WEXITED|WNOWAIT) == 0); assert(info.si_pid == leader && info.si_status == 0x0405); /* OK, it sleeps in ptrace(PTRACE_EVENT_EXEC == 0x04) */ assert(ptrace(PTRACE_CONT, leader, 0,0) == -1); assert(errno == ESRCH); assert(leader == waitpid(leader, &status, WNOHANG)); assert(status == 0x04057f); assert(ptrace(PTRACE_CONT, leader, 0,0) == 0); return 0; } Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reported-by: Simon Marchi <simon.marchi@efficios.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Pedro Alves <palves@redhat.com> Acked-by: Simon Marchi <simon.marchi@efficios.com> Acked-by: Jan Kratochvil <jan.kratochvil@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-09Merge tag 'sched-urgent-2021-05-09' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Thomas Gleixner: "A set of scheduler updates: - Prevent PSI state corruption when schedule() races with cgroup move. A recent commit combined two PSI callbacks to reduce the number of cgroup tree updates, but missed that schedule() can drop rq::lock for load balancing, which opens the race window for cgroup_move_task() which then observes half updated state. The fix is to solely use task::ps_flags instead of looking at the potentially mismatching scheduler state - Prevent an out-of-bounds access in uclamp caused bu a rounding division which can lead to an off-by-one error exceeding the buckets array size. - Prevent unfairness caused by missing load decay when a task is attached to a cfs runqueue. The old load of the task was attached to the runqueue and never removed. Fix it by enforcing the load update through the hierarchy for unthrottled run queue instances. - A documentation fix fot the 'sched_verbose' command line option" * tag 'sched-urgent-2021-05-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/fair: Fix unfairness caused by missing load decay sched: Fix out-of-bound access in uclamp psi: Fix psi state corruption when schedule() races with cgroup move sched,doc: sched_debug_verbose cmdline should be sched_verbose
2021-05-09Merge tag 'locking-urgent-2021-05-09' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Thomas Gleixner: "A set of locking related fixes and updates: - Two fixes for the futex syscall related to the timeout handling. FUTEX_LOCK_PI does not support the FUTEX_CLOCK_REALTIME bit and because it's not set the time namespace adjustment for clock MONOTONIC is applied wrongly. FUTEX_WAIT cannot support the FUTEX_CLOCK_REALTIME bit because its always a relative timeout. - Cleanups in the futex syscall entry points which became obvious when the two timeout handling bugs were fixed. - Cleanup of queued_write_lock_slowpath() as suggested by Linus - Fixup of the smp_call_function_single_async() prototype" * tag 'locking-urgent-2021-05-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: futex: Make syscall entry points less convoluted futex: Get rid of the val2 conditional dance futex: Do not apply time namespace adjustment on FUTEX_LOCK_PI Revert 337f13046ff0 ("futex: Allow FUTEX_CLOCK_REALTIME with FUTEX_WAIT op") locking/qrwlock: Cleanup queued_write_lock_slowpath() smp: Fix smp_call_function_single_async prototype
2021-05-08Merge tag 'kbuild-v5.13-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull more Kbuild updates from Masahiro Yamada: - Convert sh and sparc to use generic shell scripts to generate the syscall headers - refactor .gitignore files - Update kernel/config_data.gz only when the content of the .config is really changed, which avoids the unneeded re-link of vmlinux - move "remove stale files" workarounds to scripts/remove-stale-files - suppress unused-but-set-variable warnings by default for Clang as well - fix locale setting LANG=C to LC_ALL=C - improve 'make distclean' - always keep intermediate objects from scripts/link-vmlinux.sh - move IF_ENABLED out of <linux/kconfig.h> to make it self-contained - misc cleanups * tag 'kbuild-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits) linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h> kbuild: Don't remove link-vmlinux temporary files on exit/signal kbuild: remove the unneeded comments for external module builds kbuild: make distclean remove tag files in sub-directories kbuild: make distclean work against $(objtree) instead of $(srctree) kbuild: refactor modname-multi by using suffix-search kbuild: refactor fdtoverlay rule kbuild: parameterize the .o part of suffix-search arch: use cross_compiling to check whether it is a cross build or not kbuild: remove ARCH=sh64 support from top Makefile .gitignore: prefix local generated files with a slash kbuild: replace LANG=C with LC_ALL=C Makefile: Move -Wno-unused-but-set-variable out of GCC only block kbuild: add a script to remove stale generated files kbuild: update config_data.gz only when the content of .config is changed .gitignore: ignore only top-level modules.builtin .gitignore: move tags and TAGS close to other tag files kernel/.gitgnore: remove stale timeconst.h and hz.bc usr/include: refactor .gitignore genksyms: fix stale comment ...
2021-05-08Merge tag 'net-5.13-rc1' 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-rc1, including fixes from bpf, can and netfilter trees. Self-contained fixes, nothing risky. Current release - new code bugs: - dsa: ksz: fix a few bugs found by static-checker in the new driver - stmmac: fix frame preemption handshake not triggering after interface restart Previous releases - regressions: - make nla_strcmp handle more then one trailing null character - fix stack OOB reads while fragmenting IPv4 packets in openvswitch and net/sched - sctp: do asoc update earlier in sctp_sf_do_dupcook_a - sctp: delay auto_asconf init until binding the first addr - stmmac: clear receive all(RA) bit when promiscuous mode is off - can: mcp251x: fix resume from sleep before interface was brought up Previous releases - always broken: - bpf: fix leakage of uninitialized bpf stack under speculation - bpf: fix masking negation logic upon negative dst register - netfilter: don't assume that skb_header_pointer() will never fail - only allow init netns to set default tcp cong to a restricted algo - xsk: fix xp_aligned_validate_desc() when len == chunk_size to avoid false positive errors - ethtool: fix missing NLM_F_MULTI flag when dumping - can: m_can: m_can_tx_work_queue(): fix tx_skb race condition - sctp: fix a SCTP_MIB_CURRESTAB leak in sctp_sf_do_dupcook_b - bridge: fix NULL-deref caused by a races between assigning rx_handler_data and setting the IFF_BRIDGE_PORT bit Latecomer: - seg6: add counters support for SRv6 Behaviors" * tag 'net-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (73 commits) atm: firestream: Use fallthrough pseudo-keyword net: stmmac: Do not enable RX FIFO overflow interrupts mptcp: fix splat when closing unaccepted socket i40e: Remove LLDP frame filters i40e: Fix PHY type identifiers for 2.5G and 5G adapters i40e: fix the restart auto-negotiation after FEC modified i40e: Fix use-after-free in i40e_client_subtask() i40e: fix broken XDP support netfilter: nftables: avoid potential overflows on 32bit arches netfilter: nftables: avoid overflows in nft_hash_buckets() tcp: Specify cmsgbuf is user pointer for receive zerocopy. mlxsw: spectrum_mr: Update egress RIF list before route's action net: ipa: fix inter-EE IRQ register definitions can: m_can: m_can_tx_work_queue(): fix tx_skb race condition can: mcp251x: fix resume from sleep before interface was brought up can: mcp251xfd: mcp251xfd_probe(): add missing can_rx_offload_del() in error path can: mcp251xfd: mcp251xfd_probe(): fix an error pointer dereference in probe netfilter: nftables: Fix a memleak from userdata error path in new objects netfilter: remove BUG_ON() after skb_header_pointer() netfilter: nfnetlink_osf: Fix a missing skb_header_pointer() NULL check ...
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 ...
2021-05-07kernel/sys.c: fix typoXiaofeng Cao
change 'infite' to 'infinite' change 'concurent' to 'concurrent' change 'memvers' to 'members' change 'decendants' to 'descendants' change 'argumets' to 'arguments' Link: https://lkml.kernel.org/r/20210316112904.10661-1-cxfcosmos@gmail.com Signed-off-by: Xiaofeng Cao <caoxiaofeng@yulong.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kernel/up.c: fix typoBhaskar Chowdhury
s/condtions/conditions/ Link: https://lkml.kernel.org/r/20210317032732.3260835-1-unixbhaskar@gmail.com Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kernel/user_namespace.c: fix typosXiaofeng Cao
change 'verifing' to 'verifying' change 'certaint' to 'certain' change 'approprpiate' to 'appropriate' Link: https://lkml.kernel.org/r/20210317100129.12440-1-caoxiaofeng@yulong.com Signed-off-by: Xiaofeng Cao <caoxiaofeng@yulong.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kernel/umh.c: fix some spelling mistakeszhouchuangao
Fix some spelling mistakes, and modify the order of the parameter comments to be consistent with the order of the parameters passed to the function. Link: https://lkml.kernel.org/r/1615636139-4076-1-git-send-email-zhouchuangao@vivo.com Signed-off-by: zhouchuangao <zhouchuangao@vivo.com> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07drivers/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>
2021-05-07modules: add CONFIG_MODPROBE_PATHRasmus Villemoes
Allow the developer to specifiy the initial value of the modprobe_path[] string. This can be used to set it to the empty string initially, thus effectively disabling request_module() during early boot until userspace writes a new value via the /proc/sys/kernel/modprobe interface. [1] When building a custom kernel (often for an embedded target), it's normal to build everything into the kernel that is needed for booting, and indeed the initramfs often contains no modules at all, so every such request_module() done before userspace init has mounted the real rootfs is a waste of time. This is particularly useful when combined with the previous patch, which made the initramfs unpacking asynchronous - for that to work, it had to make any usermodehelper call wait for the unpacking to finish before attempting to invoke the userspace helper. By eliminating all such (known-to-be-futile) calls of usermodehelper, the initramfs unpacking and the {device,late}_initcalls can proceed in parallel for much longer. For a relatively slow ppc board I'm working on, the two patches combined lead to 0.2s faster boot - but more importantly, the fact that the initramfs unpacking proceeds completely in the background while devices get probed means I get to handle the gpio watchdog in time without getting reset. [1] __request_module() already has an early -ENOENT return when modprobe_path is the empty string. Link: https://lkml.kernel.org/r/20210313212528.2956377-3-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Jessica Yu <jeyu@kernel.org> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jonathan Corbet <corbet@lwn.net> 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>
2021-05-07init/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>
2021-05-07kernel/async.c: remove async_unregister_domain()Rasmus Villemoes
No callers in the tree. Link: https://lkml.kernel.org/r/20210309151723.1907838-2-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kernel/async.c: stop guarding pr_debug() statementsRasmus Villemoes
It's currently nigh impossible to get these pr_debug()s to print something. Being guarded by initcall_debug means one has to enable tons of other debug output during boot, and the system_state condition further means it's impossible to get them when loading modules later. Also, the compiler can't know that these global conditions do not change, so there are W=2 warnings kernel/async.c:125:9: warning: `calltime' may be used uninitialized in this function [-Wmaybe-uninitialized] kernel/async.c:300:9: warning: `starttime' may be used uninitialized in this function [-Wmaybe-uninitialized] Make it possible, for a DYNAMIC_DEBUG kernel, to get these to print their messages by booting with appropriate 'dyndbg="file async.c +p"' command line argument. For a non-DYNAMIC_DEBUG kernel, pr_debug() compiles to nothing. This does cost doing an unconditional ktime_get() for the starttime value, but the corresponding ktime_get for the end time can be elided by factoring it into a function which only gets called if the printk() arguments end up being evaluated. Link: https://lkml.kernel.org/r/20210309151723.1907838-1-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kernel/resource: fix locking in request_free_mem_regionAlistair Popple
request_free_mem_region() is used to find an empty range of physical addresses for hotplugging ZONE_DEVICE memory. It does this by iterating over the range of possible addresses using region_intersects() to see if the range is free before calling request_mem_region() to allocate the region. However the resource_lock is dropped between these two calls meaning by the time request_mem_region() is called in request_free_mem_region() another thread may have already reserved the requested region. This results in unexpected failures and a message in the kernel log from hitting this condition: /* * mm/hmm.c reserves physical addresses which then * become unavailable to other users. Conflicts are * not expected. Warn to aid debugging if encountered. */ if (conflict->desc == IORES_DESC_DEVICE_PRIVATE_MEMORY) { pr_warn("Unaddressable device %s %pR conflicts with %pR", conflict->name, conflict, res); These unexpected failures can be corrected by holding resource_lock across the two calls. This also requires memory allocation to be performed prior to taking the lock. Link: https://lkml.kernel.org/r/20210419070109.4780-3-apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Muchun Song <smuchun@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kernel/resource: refactor __request_region to allow external lockingAlistair Popple
Refactor the portion of __request_region() done whilst holding the resource_lock into a separate function to allow callers to hold the lock. Link: https://lkml.kernel.org/r/20210419070109.4780-2-apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Muchun Song <smuchun@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kernel/resource: allow region_intersects users to hold resource_lockAlistair Popple
Introduce a version of region_intersects() that can be called with the resource_lock already held. This will be used in a future fix to __request_free_mem_region(). [akpm@linux-foundation.org: make __region_intersects static] Link: https://lkml.kernel.org/r/20210419070109.4780-1-apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Cc: David Hildenbrand <david@redhat.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Muchun Song <smuchun@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kernel/resource: remove first_lvl / siblings_only logicDavid Hildenbrand
All functions that search for IORESOURCE_SYSTEM_RAM or IORESOURCE_MEM resources now properly consider the whole resource tree, not just the first level. Let's drop the unused first_lvl / siblings_only logic. Remove documentation that indicates that some functions behave differently, all consider the full resource tree now. Link: https://lkml.kernel.org/r/20210325115326.7826-4-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Qian Cai <cai@lca.pw> Cc: Oscar Salvador <osalvador@suse.de> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kernel/resource: make walk_mem_res() find all busy IORESOURCE_MEM resourcesDavid Hildenbrand
It used to be true that we can have system RAM (IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY) only on the first level in the resource tree. However, this is no longer holds for driver-managed system RAM (i.e., added via dax/kmem and virtio-mem), which gets added on lower levels, for example, inside device containers. IORESOURCE_SYSTEM_RAM is defined as IORESOURCE_MEM | IORESOURCE_SYSRAM and just a special type of IORESOURCE_MEM. The function walk_mem_res() only considers the first level and is used in arch/x86/mm/ioremap.c:__ioremap_check_mem() only. We currently fail to identify System RAM added by dax/kmem and virtio-mem as "IORES_MAP_SYSTEM_RAM", for example, allowing for remapping of such "normal RAM" in __ioremap_caller(). Let's find all IORESOURCE_MEM | IORESOURCE_BUSY resources, making the function behave similar to walk_system_ram_res(). Link: https://lkml.kernel.org/r/20210325115326.7826-3-david@redhat.com Fixes: ebf71552bb0e ("virtio-mem: Add parent resource for all added "System RAM"") Fixes: c221c0b0308f ("device-dax: "Hotplug" persistent memory for use like normal RAM") Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Qian Cai <cai@lca.pw> Cc: Oscar Salvador <osalvador@suse.de> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kernel/resource: make walk_system_ram_res() find all busy ↵David Hildenbrand
IORESOURCE_SYSTEM_RAM resources Patch series "kernel/resource: make walk_system_ram_res() and walk_mem_res() search the whole tree", v2. Playing with kdump+virtio-mem I noticed that kexec_file_load() does not consider System RAM added via dax/kmem and virtio-mem when preparing the elf header for kdump. Looking into the details, the logic used in walk_system_ram_res() and walk_mem_res() seems to be outdated. walk_system_ram_range() already does the right thing, let's change walk_system_ram_res() and walk_mem_res(), and clean up. Loading a kdump kernel via "kexec -p -s" ... will result in the kdump kernel to also dump dax/kmem and virtio-mem added System RAM now. Note: kexec-tools on x86-64 also have to be updated to consider this memory in the kexec_load() case when processing /proc/iomem. This patch (of 3): It used to be true that we can have system RAM (IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY) only on the first level in the resource tree. However, this is no longer holds for driver-managed system RAM (i.e., added via dax/kmem and virtio-mem), which gets added on lower levels, for example, inside device containers. We have two users of walk_system_ram_res(), which currently only consideres the first level: a) kernel/kexec_file.c:kexec_walk_resources() -- We properly skip IORESOURCE_SYSRAM_DRIVER_MANAGED resources via locate_mem_hole_callback(), so even after this change, we won't be placing kexec images onto dax/kmem and virtio-mem added memory. No change. b) arch/x86/kernel/crash.c:fill_up_crash_elf_data() -- we're currently not adding relevant ranges to the crash elf header, resulting in them not getting dumped via kdump. This change fixes loading a crashkernel via kexec_file_load() and including dax/kmem and virtio-mem added System RAM in the crashdump on x86-64. Note that e.g,, arm64 relies on memblock data and, therefore, always considers all added System RAM already. Let's find all IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY resources, making the function behave like walk_system_ram_range(). Link: https://lkml.kernel.org/r/20210325115326.7826-1-david@redhat.com Link: https://lkml.kernel.org/r/20210325115326.7826-2-david@redhat.com Fixes: ebf71552bb0e ("virtio-mem: Add parent resource for all added "System RAM"") Fixes: c221c0b0308f ("device-dax: "Hotplug" persistent memory for use like normal RAM") Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Qian Cai <cai@lca.pw> Cc: Oscar Salvador <osalvador@suse.de> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07gcov: clang: drop support for clang-10 and olderNick Desaulniers
LLVM changed the expected function signatures for llvm_gcda_start_file() and llvm_gcda_emit_function() in the clang-11 release. Drop the older implementations and require folks to upgrade their compiler if they're interested in GCOV support. Link: https://reviews.llvm.org/rGcdd683b516d147925212724b09ec6fb792a40041 Link: https://reviews.llvm.org/rG13a633b438b6500ecad9e4f936ebadf3411d0f44 Link: https://lkml.kernel.org/r/20210312224132.3413602-3-ndesaulniers@google.com Link: https://lkml.kernel.org/r/20210413183113.2977432-1-ndesaulniers@google.com Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Suggested-by: Nathan Chancellor <nathan@kernel.org> Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Fangrui Song <maskray@google.com> Cc: Prasad Sodagudi <psodagud@quicinc.com> Cc: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07gcov: use kvmalloc()Johannes Berg
Using vmalloc() in gcov is really quite wasteful, many of the objects allocated are really small (e.g. I've seen 24 bytes.) Use kvmalloc() to automatically pick the better of kmalloc() or vmalloc() depending on the size. [johannes.berg@intel.com: fix clang-11+ build] Link: https://lkml.kernel.org/r/20210412214210.6e1ecca9cdc5.I24459763acf0591d5e6b31c7e3a59890d802f79c@changeid Link: https://lkml.kernel.org/r/20210315235453.799e7a9d627d.I741d0db096c6f312910f7f1bcdfde0fda20801a4@changeid Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Cc: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07gcov: simplify buffer allocationJohannes Berg
Use just a single vmalloc() with struct_size() instead of a separate kmalloc() for the iter struct. Link: https://lkml.kernel.org/r/20210315235453.b6de4a92096e.Iac40a5166589cefbff8449e466bd1b38ea7a17af@changeid Signed-off-by: Johannes Berg <johannes.berg@intel.com> Cc: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07gcov: combine common codeJohannes Berg
There's a lot of duplicated code between gcc and clang implementations, move it over to fs.c to simplify the code, there's no reason to believe that for small data like this one would not just implement the simple convert_to_gcda() function. Link: https://lkml.kernel.org/r/20210315235453.e3fbb86e99a0.I08a3ee6dbe47ea3e8024956083f162884a958e40@changeid Signed-off-by: Johannes Berg <johannes.berg@intel.com> Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kexec: dump kmessage before machine_kexecPavel Tatashin
kmsg_dump(KMSG_DUMP_SHUTDOWN) is called before machine_restart(), machine_halt(), and machine_power_off(). The only one that is missing is machine_kexec(). The dmesg output that it contains can be used to study the shutdown performance of both kernel and systemd during kexec reboot. Here is example of dmesg data collected after kexec: root@dplat-cp22:~# cat /sys/fs/pstore/dmesg-ramoops-0 | tail ... [ 70.914592] psci: CPU3 killed (polled 0 ms) [ 70.915705] CPU4: shutdown [ 70.916643] psci: CPU4 killed (polled 4 ms) [ 70.917715] CPU5: shutdown [ 70.918725] psci: CPU5 killed (polled 0 ms) [ 70.919704] CPU6: shutdown [ 70.920726] psci: CPU6 killed (polled 4 ms) [ 70.921642] CPU7: shutdown [ 70.922650] psci: CPU7 killed (polled 0 ms) Link: https://lkml.kernel.org/r/20210319192326.146000-2-pasha.tatashin@soleen.com Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com> Cc: James Morris <jmorris@namei.org> Cc: Sasha Levin <sashal@kernel.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kernel: kexec_file: fix error return code of kexec_calculate_store_digests()Jia-Ju Bai
When vzalloc() returns NULL to sha_regions, no error return code of kexec_calculate_store_digests() is assigned. To fix this bug, ret is assigned with -ENOMEM in this case. Link: https://lkml.kernel.org/r/20210309083904.24321-1-baijiaju1990@gmail.com Fixes: a43cac0d9dc2 ("kexec: split kexec_file syscall code to kexec_file.c") Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Reported-by: TOTE Robot <oslab@tsinghua.edu.cn> Acked-by: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07kexec: Add kexec reboot stringJoe LeVeque
The purpose is to notify the kernel module for fast reboot. Upstream a patch from the SONiC network operating system [1]. [1]: https://github.com/Azure/sonic-linux-kernel/pull/46 Link: https://lkml.kernel.org/r/20210304124626.13927-1-pmenzel@molgen.mpg.de Signed-off-by: Joe LeVeque <jolevequ@microsoft.com> Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de> Acked-by: Baoquan He <bhe@redhat.com> Cc: Guohan Lu <lguohan@gmail.com> Cc: Joe LeVeque <jolevequ@microsoft.com> Cc: Paul Menzel <pmenzel@molgen.mpg.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06kernel/fork.c: fix typosXiaofeng Cao
change 'ancestoral' to 'ancestral' change 'reuseable' to 'reusable' delete 'do' grammatically Link: https://lkml.kernel.org/r/20210317082031.11692-1-caoxiaofeng@yulong.com Signed-off-by: Xiaofeng Cao <caoxiaofeng@yulong.com> Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06kernel/fork.c: simplify copy_mm()Rolf Eike Beer
All this can happen without a single goto. Link: https://lkml.kernel.org/r/2072685.XptgVkyDqn@devpool47 Signed-off-by: Rolf Eike Beer <eb@emlix.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06do_wait: make PIDTYPE_PID case O(1) instead of O(n)Jim Newsome
Add a special-case when waiting on a pid (via waitpid, waitid, wait4, etc) to avoid doing an O(n) scan of children and tracees, and instead do an O(1) lookup. This improves performance when waiting on a pid from a thread group with many children and/or tracees. Time to fork and then call waitpid on the child, from a task that already has N children [1]: N | Before | After -----|---------|------ 1 | 74 us | 74 us 20 | 72 us | 75 us 100 | 83 us | 77 us 500 | 99 us | 74 us 1000 | 179 us | 75 us 5000 | 804 us | 79 us 8000 | 1268 us | 78 us [1]: https://lkml.org/lkml/2021/3/12/1567 This can make a substantial performance improvement for applications with a thread that has many children or tracees and frequently needs to wait on them. Tools that use ptrace to intercept syscalls for a large number of processes are likely to fall into this category. In particular this patch was developed while building a ptrace-based second generation of the Shadow emulator [2], for which it allows us to avoid quadratic scaling (without having to use a workaround that introduces a ~40% performance penalty) [3]. Other examples of tools that fall into this category which this patch may help include User Mode Linux [4] and DetTrace [5]. [2]: https://shadow.github.io/ [3]: https://github.com/shadow/shadow/issues/1134#issuecomment-798992292 [4]: https://en.wikipedia.org/wiki/User-mode_Linux [5]: https://github.com/dettrace/dettrace Link: https://lkml.kernel.org/r/20210314231544.9379-1-jnewsome@torproject.org Signed-off-by: James Newsome <jnewsome@torproject.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: Christian Brauner <christian@brauner.io> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06kernel/cred.c: make init_groups staticRasmus Villemoes
init_groups is declared in both cred.h and init_task.h, but it is not actually referenced anywhere outside of cred.c where it is defined. So make it static and remove the declarations. Link: https://lkml.kernel.org/r/20210310220102.2484201-1-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06kernel/async.c: fix pr_debug statementRasmus Villemoes
An async_func_t returns void - any errors encountered it has to stash somewhere for consumers to discover later. Link: https://lkml.kernel.org/r/20210226124355.2503524-1-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-06futex: Make syscall entry points less convolutedThomas Gleixner
The futex and the compat syscall entry points do pretty much the same except for the timespec data types and the corresponding copy from user function. Split out the rest into inline functions and share the functionality. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20210422194705.244476369@linutronix.de
2021-05-06futex: Get rid of the val2 conditional danceThomas Gleixner
There is no point in checking which FUTEX operand treats the utime pointer as 'val2' argument because that argument to do_futex() is only used by exactly these operands. So just handing it in unconditionally is not making any difference, but removes a lot of pointless gunk. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20210422194705.125957049@linutronix.de
2021-05-06futex: Do not apply time namespace adjustment on FUTEX_LOCK_PIThomas Gleixner
FUTEX_LOCK_PI does not require to have the FUTEX_CLOCK_REALTIME bit set because it has been using CLOCK_REALTIME based absolute timeouts forever. Due to that, the time namespace adjustment which is applied when FUTEX_CLOCK_REALTIME is not set, will wrongly take place for FUTEX_LOCK_PI and wreckage the timeout. Exclude it from that procedure. Fixes: c2f7d08cccf4 ("futex: Adjust absolute futex timeouts with per time namespace offset") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210422194704.984540159@linutronix.de
2021-05-06Revert 337f13046ff0 ("futex: Allow FUTEX_CLOCK_REALTIME with FUTEX_WAIT op")Thomas Gleixner
The FUTEX_WAIT operand has historically a relative timeout which means that the clock id is irrelevant as relative timeouts on CLOCK_REALTIME are not subject to wall clock changes and therefore are mapped by the kernel to CLOCK_MONOTONIC for simplicity. If a caller would set FUTEX_CLOCK_REALTIME for FUTEX_WAIT the timeout is still treated relative vs. CLOCK_MONOTONIC and then the wait arms that timeout based on CLOCK_REALTIME which is broken and obviously has never been used or even tested. Reject any attempt to use FUTEX_CLOCK_REALTIME with FUTEX_WAIT again. The desired functionality can be achieved with FUTEX_WAIT_BITSET and a FUTEX_BITSET_MATCH_ANY argument. Fixes: 337f13046ff0 ("futex: Allow FUTEX_CLOCK_REALTIME with FUTEX_WAIT op") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210422194704.834797921@linutronix.de
2021-05-06Merge tag 'trace-v5.13-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fix from Steven Rostedt: "Fix probes written to the set_ftrace_filter file Now that there's a library that accesses the tracefs file system (libtracefs), the way the files are interacted with is slightly different than the command line. For instance, the write() system call is used directly instead of an echo. This exposes some old bugs. If a probe is written to "set_ftrace_filter" without any white space after it, it will be ignored. This is because the write expects that a string written to it that does not end with white spaces thinks there is more to come. But if the file is closed, the release function needs to finish it. The "set_ftrace_filter" release function handles the filter part of the "set_ftrace_filter" file, but did not handle the probe part" * tag 'trace-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace: Handle commands when closing set_ftrace_filter file
2021-05-06locking/qrwlock: Cleanup queued_write_lock_slowpath()Waiman Long
Make the code more readable by replacing the atomic_cmpxchg_acquire() by an equivalent atomic_try_cmpxchg_acquire() and change atomic_add() to atomic_or(). For architectures that use qrwlock, I do not find one that has an atomic_add() defined but not an atomic_or(). I guess it should be fine by changing atomic_add() to atomic_or(). Note that the previous use of atomic_add() isn't wrong as only one writer that is the wait_lock owner can set the waiting flag and the flag will be cleared later on when acquiring the write lock. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Will Deacon <will@kernel.org> Link: https://lkml.kernel.org/r/20210426185017.19815-1-longman@redhat.com
2021-05-06smp: Fix smp_call_function_single_async prototypeArnd Bergmann
As of commit 966a967116e6 ("smp: Avoid using two cache lines for struct call_single_data"), the smp code prefers 32-byte aligned call_single_data objects for performance reasons, but the block layer includes an instance of this structure in the main 'struct request' that is more senstive to size than to performance here, see 4ccafe032005 ("block: unalign call_single_data in struct request"). The result is a violation of the calling conventions that clang correctly points out: block/blk-mq.c:630:39: warning: passing 8-byte aligned argument to 32-byte aligned parameter 2 of 'smp_call_function_single_async' may result in an unaligned pointer access [-Walign-mismatch] smp_call_function_single_async(cpu, &rq->csd); It does seem that the usage of the call_single_data without cache line alignment should still be allowed by the smp code, so just change the function prototype so it accepts both, but leave the default alignment unchanged for the other users. This seems better to me than adding a local hack to shut up an otherwise correct warning in the caller. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Jens Axboe <axboe@kernel.dk> Link: https://lkml.kernel.org/r/20210505211300.3174456-1-arnd@kernel.org
2021-05-06sched/fair: Fix unfairness caused by missing load decayOdin Ugedal
This fixes an issue where old load on a cfs_rq is not properly decayed, resulting in strange behavior where fairness can decrease drastically. Real workloads with equally weighted control groups have ended up getting a respective 99% and 1%(!!) of cpu time. When an idle task is attached to a cfs_rq by attaching a pid to a cgroup, the old load of the task is attached to the new cfs_rq and sched_entity by attach_entity_cfs_rq. If the task is then moved to another cpu (and therefore cfs_rq) before being enqueued/woken up, the load will be moved to cfs_rq->removed from the sched_entity. Such a move will happen when enforcing a cpuset on the task (eg. via a cgroup) that force it to move. The load will however not be removed from the task_group itself, making it look like there is a constant load on that cfs_rq. This causes the vruntime of tasks on other sibling cfs_rq's to increase faster than they are supposed to; causing severe fairness issues. If no other task is started on the given cfs_rq, and due to the cpuset it would not happen, this load would never be properly unloaded. With this patch the load will be properly removed inside update_blocked_averages. This also applies to tasks moved to the fair scheduling class and moved to another cpu, and this path will also fix that. For fork, the entity is queued right away, so this problem does not affect that. This applies to cases where the new process is the first in the cfs_rq, issue introduced 3d30544f0212 ("sched/fair: Apply more PELT fixes"), and when there has previously been load on the cgroup but the cgroup was removed from the leaflist due to having null PELT load, indroduced in 039ae8bcf7a5 ("sched/fair: Fix O(nr_cgroups) in the load balancing path"). For a simple cgroup hierarchy (as seen below) with two equally weighted groups, that in theory should get 50/50 of cpu time each, it often leads to a load of 60/40 or 70/30. parent/ cg-1/ cpu.weight: 100 cpuset.cpus: 1 cg-2/ cpu.weight: 100 cpuset.cpus: 1 If the hierarchy is deeper (as seen below), while keeping cg-1 and cg-2 equally weighted, they should still get a 50/50 balance of cpu time. This however sometimes results in a balance of 10/90 or 1/99(!!) between the task groups. $ ps u -C stress USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 18568 1.1 0.0 3684 100 pts/12 R+ 13:36 0:00 stress --cpu 1 root 18580 99.3 0.0 3684 100 pts/12 R+ 13:36 0:09 stress --cpu 1 parent/ cg-1/ cpu.weight: 100 sub-group/ cpu.weight: 1 cpuset.cpus: 1 cg-2/ cpu.weight: 100 sub-group/ cpu.weight: 10000 cpuset.cpus: 1 This can be reproduced by attaching an idle process to a cgroup and moving it to a given cpuset before it wakes up. The issue is evident in many (if not most) container runtimes, and has been reproduced with both crun and runc (and therefore docker and all its "derivatives"), and with both cgroup v1 and v2. Fixes: 3d30544f0212 ("sched/fair: Apply more PELT fixes") Fixes: 039ae8bcf7a5 ("sched/fair: Fix O(nr_cgroups) in the load balancing path") Signed-off-by: Odin Ugedal <odin@uged.al> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lkml.kernel.org/r/20210501141950.23622-2-odin@uged.al
2021-05-06sched: Fix out-of-bound access in uclampQuentin Perret
Util-clamp places tasks in different buckets based on their clamp values for performance reasons. However, the size of buckets is currently computed using a rounding division, which can lead to an off-by-one error in some configurations. For instance, with 20 buckets, the bucket size will be 1024/20=51. A task with a clamp of 1024 will be mapped to bucket id 1024/51=20. Sadly, correct indexes are in range [0,19], hence leading to an out of bound memory access. Clamp the bucket id to fix the issue. Fixes: 69842cba9ace ("sched/uclamp: Add CPU's clamp buckets refcounting") Suggested-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Link: https://lkml.kernel.org/r/20210430151412.160913-1-qperret@google.com
2021-05-06psi: Fix psi state corruption when schedule() races with cgroup moveJohannes Weiner
4117cebf1a9f ("psi: Optimize task switch inside shared cgroups") introduced a race condition that corrupts internal psi state. This manifests as kernel warnings, sometimes followed by bogusly high IO pressure: psi: task underflow! cpu=1 t=2 tasks=[0 0 0 0] clear=c set=0 (schedule() decreasing RUNNING and ONCPU, both of which are 0) psi: incosistent task state! task=2412744:systemd cpu=17 psi_flags=e clear=3 set=0 (cgroup_move_task() clearing MEMSTALL and IOWAIT, but task is MEMSTALL | RUNNING | ONCPU) What the offending commit does is batch the two psi callbacks in schedule() to reduce the number of cgroup tree updates. When prev is deactivated and removed from the runqueue, nothing is done in psi at first; when the task switch completes, TSK_RUNNING and TSK_IOWAIT are updated along with TSK_ONCPU. However, the deactivation and the task switch inside schedule() aren't atomic: pick_next_task() may drop the rq lock for load balancing. When this happens, cgroup_move_task() can run after the task has been physically dequeued, but the psi updates are still pending. Since it looks at the task's scheduler state, it doesn't move everything to the new cgroup that the task switch that follows is about to clear from it. cgroup_move_task() will leak the TSK_RUNNING count in the old cgroup, and psi_sched_switch() will underflow it in the new cgroup. A similar thing can happen for iowait. TSK_IOWAIT is usually set when a p->in_iowait task is dequeued, but again this update is deferred to the switch. cgroup_move_task() can see an unqueued p->in_iowait task and move a non-existent TSK_IOWAIT. This results in the inconsistent task state warning, as well as a counter underflow that will result in permanent IO ghost pressure being reported. Fix this bug by making cgroup_move_task() use task->psi_flags instead of looking at the potentially mismatching scheduler state. [ We used the scheduler state historically in order to not rely on task->psi_flags for anything but debugging. But that ship has sailed anyway, and this is simpler and more robust. We previously already batched TSK_ONCPU clearing with the TSK_RUNNING update inside the deactivation call from schedule(). But that ordering was safe and didn't result in TSK_ONCPU corruption: unlike most places in the scheduler, cgroup_move_task() only checked task_current() and handled TSK_ONCPU if the task was still queued. ] Fixes: 4117cebf1a9f ("psi: Optimize task switch inside shared cgroups") Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210503174917.38579-1-hannes@cmpxchg.org
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/compaction: remove unused variable sysctl_compact_memoryPintu Kumar
The sysctl_compact_memory is mostly unused in mm/compaction.c It just acts as a place holder for sysctl to store .data. But the .data itself is not needed here. So we can get ride of this variable completely and make .data as NULL. This will also eliminate the extern declaration from header file. No functionality is broken or changed this way. Link: https://lkml.kernel.org/r/1614852224-14671-1-git-send-email-pintu@codeaurora.org Signed-off-by: Pintu Kumar <pintu@codeaurora.org> Signed-off-by: Pintu Agarwal <pintu.ping@gmail.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05ftrace: Handle commands when closing set_ftrace_filter fileSteven Rostedt (VMware)
# echo switch_mm:traceoff > /sys/kernel/tracing/set_ftrace_filter will cause switch_mm to stop tracing by the traceoff command. # echo -n switch_mm:traceoff > /sys/kernel/tracing/set_ftrace_filter does nothing. The reason is that the parsing in the write function only processes commands if it finished parsing (there is white space written after the command). That's to handle: write(fd, "switch_mm:", 10); write(fd, "traceoff", 8); cases, where the command is broken over multiple writes. The problem is if the file descriptor is closed, then the write call is not processed, and the command needs to be processed in the release code. The release code can handle matching of functions, but does not handle commands. Cc: stable@vger.kernel.org Fixes: eda1e32855656 ("tracing: handle broken names in ftrace filter") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-05-04Merge branch 'stable/for-linus-5.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb Pull swiotlb updates from Konrad Rzeszutek Wilk: "Christoph Hellwig has taken a cleaver and trimmed off the not-needed code and nicely folded duplicate code in the generic framework. This lays the groundwork for more work to add extra DMA-backend-ish in the future. Along with that some bug-fixes to make this a nice working package" * 'stable/for-linus-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb: swiotlb: don't override user specified size in swiotlb_adjust_size swiotlb: Fix the type of index swiotlb: Make SWIOTLB_NO_FORCE perform no allocation ARM: Qualify enabling of swiotlb_init() swiotlb: remove swiotlb_nr_tbl swiotlb: dynamically allocate io_tlb_default_mem swiotlb: move global variables into a new io_tlb_mem structure xen-swiotlb: remove the unused size argument from xen_swiotlb_fixup xen-swiotlb: split xen_swiotlb_init swiotlb: lift the double initialization protection from xen-swiotlb xen-swiotlb: remove xen_io_tlb_start and xen_io_tlb_nslabs xen-swiotlb: remove xen_set_nslabs xen-swiotlb: use io_tlb_end in xen_swiotlb_dma_supported xen-swiotlb: use is_swiotlb_buffer in is_xen_swiotlb_buffer swiotlb: split swiotlb_tbl_sync_single swiotlb: move orig addr and size validation into swiotlb_bounce swiotlb: remove the alloc_size parameter to swiotlb_tbl_unmap_single powerpc/svm: stop using io_tlb_start
2021-05-04Merge tag 'dma-mapping-5.13' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds
Pull dma-mapping updates from Christoph Hellwig: - add a new dma_alloc_noncontiguous API (me, Ricardo Ribalda) - fix a copyright notice (Hao Fang) - add an unlikely annotation to dma_mapping_error (Heiner Kallweit) - remove a pointless empty line (Wang Qing) - add support for multi-pages map/unmap bencharking (Xiang Chen) * tag 'dma-mapping-5.13' of git://git.infradead.org/users/hch/dma-mapping: dma-mapping: add unlikely hint to error path in dma_mapping_error dma-mapping: benchmark: Add support for multi-pages map/unmap dma-mapping: benchmark: use the correct HiSilicon copyright dma-mapping: remove a pointless empty line in dma_alloc_coherent media: uvcvideo: Use dma_alloc_noncontiguous API dma-iommu: implement ->alloc_noncontiguous dma-iommu: refactor iommu_dma_alloc_remap dma-mapping: add a dma_alloc_noncontiguous API dma-mapping: refactor dma_{alloc,free}_pages dma-mapping: add a dma_mmap_pages helper
2021-05-03Merge tag 'trace-v5.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "New feature: - A new "func-no-repeats" option in tracefs/options directory. When set the function tracer will detect if the current function being traced is the same as the previous one, and instead of recording it, it will keep track of the number of times that the function is repeated in a row. And when another function is recorded, it will write a new event that shows the function that repeated, the number of times it repeated and the time stamp of when the last repeated function occurred. Enhancements: - In order to implement the above "func-no-repeats" option, the ring buffer timestamp can now give the accurate timestamp of the event as it is being recorded, instead of having to record an absolute timestamp for all events. This helps the histogram code which no longer needs to waste ring buffer space. - New validation logic to make sure all trace events that access dereferenced pointers do so in a safe way, and will warn otherwise. Fixes: - No longer limit the PIDs of tasks that are recorded for "saved_cmdlines" to PID_MAX_DEFAULT (32768), as systemd now allows for a much larger range. This caused the mapping of PIDs to the task names to be dropped for all tasks with a PID greater than 32768. - Change trace_clock_global() to never block. This caused a deadlock. Clean ups: - Typos, prototype fixes, and removing of duplicate or unused code. - Better management of ftrace_page allocations" * tag 'trace-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (32 commits) tracing: Restructure trace_clock_global() to never block tracing: Map all PIDs to command lines ftrace: Reuse the output of the function tracer for func_repeats tracing: Add "func_no_repeats" option for function tracing tracing: Unify the logic for function tracing options tracing: Add method for recording "func_repeats" events tracing: Add "last_func_repeats" to struct trace_array tracing: Define new ftrace event "func_repeats" tracing: Define static void trace_print_time() ftrace: Simplify the calculation of page number for ftrace_page->records some more ftrace: Store the order of pages allocated in ftrace_page tracing: Remove unused argument from "ring_buffer_time_stamp() tracing: Remove duplicate struct declaration in trace_events.h tracing: Update create_system_filter() kernel-doc comment tracing: A minor cleanup for create_system_filter() kernel: trace: Mundane typo fixes in the file trace_events_filter.c tracing: Fix various typos in comments scripts/recordmcount.pl: Make vim and emacs indent the same scripts/recordmcount.pl: Make indent spacing consistent tracing: Add a verifier to check string pointers for trace events ...