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* hrtimer: Report offline hrtimer enqueueFrederic Weisbecker2024-02-061-0/+3
| | | | | | | | | | | | | | | | | | | | The hrtimers migration on CPU-down hotplug process has been moved earlier, before the CPU actually goes to die. This leaves a small window of opportunity to queue an hrtimer in a blind spot, leaving it ignored. For example a practical case has been reported with RCU waking up a SCHED_FIFO task right before the CPUHP_AP_IDLE_DEAD stage, queuing that way a sched/rt timer to the local offline CPU. Make sure such situations never go unnoticed and warn when that happens. Fixes: 5c0930ccaad5 ("hrtimers: Push pending hrtimers away from outgoing CPU earlier") Reported-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240129235646.3171983-4-boqun.feng@gmail.com
* tick/sched: Preserve number of idle sleeps across CPU hotplug eventsTim Chen2024-01-251-0/+5
| | | | | | | | | | | | | | | | | Commit 71fee48f ("tick-sched: Fix idle and iowait sleeptime accounting vs CPU hotplug") preserved total idle sleep time and iowait sleeptime across CPU hotplug events. Similar reasoning applies to the number of idle calls and idle sleeps to get the proper average of sleep time per idle invocation. Preserve those fields too. Fixes: 71fee48f ("tick-sched: Fix idle and iowait sleeptime accounting vs CPU hotplug") Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240122233534.3094238-1-tim.c.chen@linux.intel.com
* clocksource: Skip watchdog check for large watchdog intervalsJiri Wiesner2024-01-251-1/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There have been reports of the watchdog marking clocksources unstable on machines with 8 NUMA nodes: clocksource: timekeeping watchdog on CPU373: Marking clocksource 'tsc' as unstable because the skew is too large: clocksource: 'hpet' wd_nsec: 14523447520 clocksource: 'tsc' cs_nsec: 14524115132 The measured clocksource skew - the absolute difference between cs_nsec and wd_nsec - was 668 microseconds: cs_nsec - wd_nsec = 14524115132 - 14523447520 = 667612 The kernel used 200 microseconds for the uncertainty_margin of both the clocksource and watchdog, resulting in a threshold of 400 microseconds (the md variable). Both the cs_nsec and the wd_nsec value indicate that the readout interval was circa 14.5 seconds. The observed behaviour is that watchdog checks failed for large readout intervals on 8 NUMA node machines. This indicates that the size of the skew was directly proportinal to the length of the readout interval on those machines. The measured clocksource skew, 668 microseconds, was evaluated against a threshold (the md variable) that is suited for readout intervals of roughly WATCHDOG_INTERVAL, i.e. HZ >> 1, which is 0.5 second. The intention of 2e27e793e280 ("clocksource: Reduce clocksource-skew threshold") was to tighten the threshold for evaluating skew and set the lower bound for the uncertainty_margin of clocksources to twice WATCHDOG_MAX_SKEW. Later in c37e85c135ce ("clocksource: Loosen clocksource watchdog constraints"), the WATCHDOG_MAX_SKEW constant was increased to 125 microseconds to fit the limit of NTP, which is able to use a clocksource that suffers from up to 500 microseconds of skew per second. Both the TSC and the HPET use default uncertainty_margin. When the readout interval gets stretched the default uncertainty_margin is no longer a suitable lower bound for evaluating skew - it imposes a limit that is far stricter than the skew with which NTP can deal. The root causes of the skew being directly proportinal to the length of the readout interval are: * the inaccuracy of the shift/mult pairs of clocksources and the watchdog * the conversion to nanoseconds is imprecise for large readout intervals Prevent this by skipping the current watchdog check if the readout interval exceeds 2 * WATCHDOG_INTERVAL. Considering the maximum readout interval of 2 * WATCHDOG_INTERVAL, the current default uncertainty margin (of the TSC and HPET) corresponds to a limit on clocksource skew of 250 ppm (microseconds of skew per second). To keep the limit imposed by NTP (500 microseconds of skew per second) for all possible readout intervals, the margins would have to be scaled so that the threshold value is proportional to the length of the actual readout interval. As for why the readout interval may get stretched: Since the watchdog is executed in softirq context the expiration of the watchdog timer can get severely delayed on account of a ksoftirqd thread not getting to run in a timely manner. Surely, a system with such belated softirq execution is not working well and the scheduling issue should be looked into but the clocksource watchdog should be able to deal with it accordingly. Fixes: 2e27e793e280 ("clocksource: Reduce clocksource-skew threshold") Suggested-by: Feng Tang <feng.tang@intel.com> Signed-off-by: Jiri Wiesner <jwiesner@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: Feng Tang <feng.tang@intel.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240122172350.GA740@incl
* Merge tag 'timers-core-2024-01-21' of ↵Linus Torvalds2024-01-211-0/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "Updates for time and clocksources: - A fix for the idle and iowait time accounting vs CPU hotplug. The time is reset on CPU hotplug which makes the accumulated systemwide time jump backwards. - Assorted fixes and improvements for clocksource/event drivers" * tag 'timers-core-2024-01-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tick-sched: Fix idle and iowait sleeptime accounting vs CPU hotplug clocksource/drivers/ep93xx: Fix error handling during probe clocksource/drivers/cadence-ttc: Fix some kernel-doc warnings clocksource/drivers/timer-ti-dm: Fix make W=n kerneldoc warnings clocksource/timer-riscv: Add riscv_clock_shutdown callback dt-bindings: timer: Add StarFive JH8100 clint dt-bindings: timer: thead,c900-aclint-mtimer: separate mtime and mtimecmp regs
| * tick-sched: Fix idle and iowait sleeptime accounting vs CPU hotplugHeiko Carstens2024-01-191-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When offlining and onlining CPUs the overall reported idle and iowait times as reported by /proc/stat jump backward and forward: cpu 132 0 176 225249 47 6 6 21 0 0 cpu0 80 0 115 112575 33 3 4 18 0 0 cpu1 52 0 60 112673 13 3 1 2 0 0 cpu 133 0 177 226681 47 6 6 21 0 0 cpu0 80 0 116 113387 33 3 4 18 0 0 cpu 133 0 178 114431 33 6 6 21 0 0 <---- jump backward cpu0 80 0 116 114247 33 3 4 18 0 0 cpu1 52 0 61 183 0 3 1 2 0 0 <---- idle + iowait start with 0 cpu 133 0 178 228956 47 6 6 21 0 0 <---- jump forward cpu0 81 0 117 114929 33 3 4 18 0 0 Reason for this is that get_idle_time() in fs/proc/stat.c has different sources for both values depending on if a CPU is online or offline: - if a CPU is online the values may be taken from its per cpu tick_cpu_sched structure - if a CPU is offline the values are taken from its per cpu cpustat structure The problem is that the per cpu tick_cpu_sched structure is set to zero on CPU offline. See tick_cancel_sched_timer() in kernel/time/tick-sched.c. Therefore when a CPU is brought offline and online afterwards both its idle and iowait sleeptime will be zero, causing a jump backward in total system idle and iowait sleeptime. In a similar way if a CPU is then brought offline again the total idle and iowait sleeptimes will jump forward. It looks like this behavior was introduced with commit 4b0c0f294f60 ("tick: Cleanup NOHZ per cpu data on cpu down"). This was only noticed now on s390, since we switched to generic idle time reporting with commit be76ea614460 ("s390/idle: remove arch_cpu_idle_time() and corresponding code"). Fix this by preserving the values of idle_sleeptime and iowait_sleeptime members of the per-cpu tick_sched structure on CPU hotplug. Fixes: 4b0c0f294f60 ("tick: Cleanup NOHZ per cpu data on cpu down") Reported-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20240115163555.1004144-1-hca@linux.ibm.com
* | Merge tag 'timers-core-2024-01-08' of ↵Linus Torvalds2024-01-083-59/+79
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer subsystem updates from Ingo Molnar: - Various preparatory cleanups & enhancements of the timer-wheel code, in preparation for the WIP 'pull timers at expiry' timer migration model series (which will replace the current 'push timers at enqueue' migration model), by Anna-Maria Behnsen: - Update comments and clean up confusing variable names - Add debug check to warn about time travel - Improve/expand timer-wheel tracepoints - Optimize away unnecessary IPIs for deferrable timers - Restructure & clean up next_expiry_recalc() - Clean up forward_timer_base() - Introduce __forward_timer_base() and use it to simplify and micro-optimize get_next_timer_interrupt() - Restructure the get_next_timer_interrupt()'s idle logic for better readability and to enable a minor optimization. - Fix the nextevt calculation when no timers are pending - Fix the sysfs_get_uname() prototype declaration * tag 'timers-core-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timers: Fix nextevt calculation when no timers are pending timers: Rework idle logic timers: Use already existing function for forwarding timer base timers: Split out forward timer base functionality timers: Clarify check in forward_timer_base() timers: Move store of next event into __next_timer_interrupt() timers: Do not IPI for deferrable timers tracing/timers: Add tracepoint for tracking timer base is_idle flag tracing/timers: Enhance timer_start tracepoint tick-sched: Warn when next tick seems to be in the past tick/sched: Cleanup confusing variables tick-sched: Fix function names in comments time: Make sysfs_get_uname() function visible in header
| * timers: Fix nextevt calculation when no timers are pendingAnna-Maria Behnsen2023-12-201-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When no timer is queued into an empty timer base, the next_expiry will not be updated. It was originally calculated as base->clk + NEXT_TIMER_MAX_DELTA When the timer base stays empty long enough (> NEXT_TIMER_MAX_DELTA), the next_expiry value of the empty base suggests that there is a timer pending soon. This might be more a kind of a theoretical problem, but the fix doesn't hurt. Use only base->next_expiry value as nextevt when timers are pending. Otherwise nextevt will be jiffies + NEXT_TIMER_MAX_DELTA. As all information is in place, update base->next_expiry value of the empty timer base as well. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-13-anna-maria@linutronix.de
| * timers: Rework idle logicThomas Gleixner2023-12-201-20/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To improve readability of the code, split base->idle calculation and expires calculation into separate parts. While at it, update the comment about timer base idle marking. Thereby the following subtle change happens if the next event is just one jiffy ahead and the tick was already stopped: Originally base->is_idle remains true in this situation. Now base->is_idle turns to false. This may spare an IPI if a timer is enqueued remotely to an idle CPU that is going to tick on the next jiffy. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-12-anna-maria@linutronix.de
| * timers: Use already existing function for forwarding timer baseAnna-Maria Behnsen2023-12-201-8/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | There is an already existing function for forwarding the timer base. Forwarding the timer base is implemented directly in get_next_timer_interrupt() as well. Remove the code duplication and invoke __forward_timer_base() instead. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-11-anna-maria@linutronix.de
| * timers: Split out forward timer base functionalityAnna-Maria Behnsen2023-12-201-6/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Forwarding timer base is done when the next expiry value is calculated and when a new timer is enqueued. When the next expiry value is calculated the jiffies value is already available and does not need to be reread a second time. Splitting out the forward timer base functionality to make it executable via both contextes - those where jiffies are already known and those, where jiffies need to be read. No functional change. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-10-anna-maria@linutronix.de
| * timers: Clarify check in forward_timer_base()Anna-Maria Behnsen2023-12-201-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current check whether a forward of the timer base is required can be simplified by using an already existing comparison function which is easier to read. The related comment is outdated and was not updated when the check changed in commit 36cd28a4cdd0 ("timers: Lower base clock forwarding threshold"). Use time_before_eq() for the check and replace the comment by copying the comment from the same check inside get_next_timer_interrupt(). Move the precious information of the outdated comment to the proper place in __run_timers(). No functional change. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-9-anna-maria@linutronix.de
| * timers: Move store of next event into __next_timer_interrupt()Anna-Maria Behnsen2023-12-201-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Both call sites of __next_timer_interrupt() store the return value directly in base->next_expiry. Move the store into __next_timer_interrupt() and to make its purpose more clear, rename the function to next_expiry_recalc(). No functional change. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-8-anna-maria@linutronix.de
| * timers: Do not IPI for deferrable timersAnna-Maria Behnsen2023-12-201-9/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Deferrable timers do not prevent CPU from going idle and are not taken into account on idle path. Sending an IPI to a remote CPU when a new first deferrable timer was enqueued will wake up the remote CPU but nothing will be done regarding the deferrable timers. Drop IPI completely when a new first deferrable timer was enqueued. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-7-anna-maria@linutronix.de
| * tracing/timers: Add tracepoint for tracking timer base is_idle flagAnna-Maria Behnsen2023-12-201-3/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | When debugging timer code the timer tracepoints are very important. There is no tracepoint when the is_idle flag of the timer base changes. Instead of always adding manually trace_printk(), add tracepoints which can be easily enabled whenever required. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-6-anna-maria@linutronix.de
| * tracing/timers: Enhance timer_start tracepointAnna-Maria Behnsen2023-12-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For starting a timer, the timer is enqueued into a bucket of the timer wheel. The bucket expiry is the defacto expiry of the timer but it is not equal the timer expiry because of increasing granularity when bucket is in a higher level of the wheel. To be able to figure out in a trace whether a timer expired in time or not, the bucket expiry time is required as well. Add bucket expiry time to the timer_start tracepoint and thereby simplify the arguments. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-5-anna-maria@linutronix.de
| * tick-sched: Warn when next tick seems to be in the pastAnna-Maria Behnsen2023-12-201-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the next tick is in the past, the delta between basemono and the next tick gets negativ. But the next tick should never be in the past. The negative effect of a wrong next tick might be a stop of the tick and timers might expire late. To prevent expensive debugging when changing underlying code, add a WARN_ON_ONCE into this code path. To prevent complete misbehaviour, also reset next_tick to basemono in this case. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-4-anna-maria@linutronix.de
| * tick/sched: Cleanup confusing variablesAnna-Maria Behnsen2023-12-201-6/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | tick_nohz_stop_tick() contains the expires (u64 variable) and tick (ktime_t) variable. In the beginning the value of expires is written to tick. Afterwards none of the variables is changed. They are only used for checks. Drop the not required variable tick and use always expires instead. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-3-anna-maria@linutronix.de
| * tick-sched: Fix function names in commentsAnna-Maria Behnsen2023-12-201-5/+5
| | | | | | | | | | | | | | | | | | | | | | When referencing functions in comments, it might be helpful to use full function names (including the prefix) to be able to find it when grepping. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-2-anna-maria@linutronix.de
| * time: Make sysfs_get_uname() function visible in headerArnd Bergmann2023-11-221-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This function is defined globally in clocksource.c and used conditionally in clockevent.c, which the declaration hidden when clockevent support is disabled. This causes a harmless warning in the definition: kernel/time/clocksource.c:1324:9: warning: no previous prototype for 'sysfs_get_uname' [-Wmissing-prototypes] 1324 | ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt) Move the declaration out of the #ifdef so it is always visible. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20231108125843.3806765-5-arnd@kernel.org
* | posix-timers: Get rid of [COMPAT_]SYS_NI() usesLinus Torvalds2023-12-201-45/+0
|/ | | | | | | | | | | | | | | | | | | | | | | Only the posix timer system calls use this (when the posix timer support is disabled, which does not actually happen in any normal case), because they had debug code to print out a warning about missing system calls. Get rid of that special case, and just use the standard COND_SYSCALL interface that creates weak system call stubs that return -ENOSYS for when the system call does not exist. This fixes a kCFI issue with the SYS_NI() hackery: CFI failure at int80_emulation+0x67/0xb0 (target: sys_ni_posix_timers+0x0/0x70; expected type: 0xb02b34d9) WARNING: CPU: 0 PID: 48 at int80_emulation+0x67/0xb0 Reported-by: kernel test robot <oliver.sang@intel.com> Reviewed-by: Sami Tolvanen <samitolvanen@google.com> Tested-by: Sami Tolvanen <samitolvanen@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'timers_urgent_for_v6.7_rc2' of ↵Linus Torvalds2023-11-191-21/+12
|\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Borislav Petkov: - Do the push of pending hrtimers away from a CPU which is being offlined earlier in the offlining process in order to prevent a deadlock * tag 'timers_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: hrtimers: Push pending hrtimers away from outgoing CPU earlier
| * hrtimers: Push pending hrtimers away from outgoing CPU earlierThomas Gleixner2023-11-111-21/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 2b8272ff4a70 ("cpu/hotplug: Prevent self deadlock on CPU hot-unplug") solved the straight forward CPU hotplug deadlock vs. the scheduler bandwidth timer. Yu discovered a more involved variant where a task which has a bandwidth timer started on the outgoing CPU holds a lock and then gets throttled. If the lock required by one of the CPU hotplug callbacks the hotplug operation deadlocks because the unthrottling timer event is not handled on the dying CPU and can only be recovered once the control CPU reaches the hotplug state which pulls the pending hrtimers from the dead CPU. Solve this by pushing the hrtimers away from the dying CPU in the dying callbacks. Nothing can queue a hrtimer on the dying CPU at that point because all other CPUs spin in stop_machine() with interrupts disabled and once the operation is finished the CPU is marked offline. Reported-by: Yu Liao <liaoyu15@huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Liu Tie <liutie4@huawei.com> Link: https://lore.kernel.org/r/87a5rphara.ffs@tglx
* | Merge tag 'net-next-6.7' of ↵Linus Torvalds2023-10-311-9/+27
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core & protocols: - Support usec resolution of TCP timestamps, enabled selectively by a route attribute. - Defer regular TCP ACK while processing socket backlog, try to send a cumulative ACK at the end. Increase single TCP flow performance on a 200Gbit NIC by 20% (100Gbit -> 120Gbit). - The Fair Queuing (FQ) packet scheduler: - add built-in 3 band prio / WRR scheduling - support bypass if the qdisc is mostly idle (5% speed up for TCP RR) - improve inactive flow reporting - optimize the layout of structures for better cache locality - Support TCP Authentication Option (RFC 5925, TCP-AO), a more modern replacement for the old MD5 option. - Add more retransmission timeout (RTO) related statistics to TCP_INFO. - Support sending fragmented skbs over vsock sockets. - Make sure we send SIGPIPE for vsock sockets if socket was shutdown(). - Add sysctl for ignoring lower limit on lifetime in Router Advertisement PIO, based on an in-progress IETF draft. - Add sysctl to control activation of TCP ping-pong mode. - Add sysctl to make connection timeout in MPTCP configurable. - Support rcvlowat and notsent_lowat on MPTCP sockets, to help apps limit the number of wakeups. - Support netlink GET for MDB (multicast forwarding), allowing user space to request a single MDB entry instead of dumping the entire table. - Support selective FDB flushing in the VXLAN tunnel driver. - Allow limiting learned FDB entries in bridges, prevent OOM attacks. - Allow controlling via configfs netconsole targets which were created via the kernel cmdline at boot, rather than via configfs at runtime. - Support multiple PTP timestamp event queue readers with different filters. - MCTP over I3C. BPF: - Add new veth-like netdevice where BPF program defines the logic of the xmit routine. It can operate in L3 and L2 mode. - Support exceptions - allow asserting conditions which should never be true but are hard for the verifier to infer. With some extra flexibility around handling of the exit / failure: https://lwn.net/Articles/938435/ - Add support for local per-cpu kptr, allow allocating and storing per-cpu objects in maps. Access to those objects operates on the value for the current CPU. This allows to deprecate local one-off implementations of per-CPU storage like BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE maps. - Extend cgroup BPF sockaddr hooks for UNIX sockets. The use case is for systemd to re-implement the LogNamespace feature which allows running multiple instances of systemd-journald to process the logs of different services. - Enable open-coded task_vma iteration, after maple tree conversion made it hard to directly walk VMAs in tracing programs. - Add open-coded task, css_task and css iterator support. One of the use cases is customizable OOM victim selection via BPF. - Allow source address selection with bpf_*_fib_lookup(). - Add ability to pin BPF timer to the current CPU. - Prevent creation of infinite loops by combining tail calls and fentry/fexit programs. - Add missed stats for kprobes to retrieve the number of missed kprobe executions and subsequent executions of BPF programs. - Inherit system settings for CPU security mitigations. - Add BPF v4 CPU instruction support for arm32 and s390x. Changes to common code: - overflow: add DEFINE_FLEX() for on-stack definition of structs with flexible array members. - Process doc update with more guidance for reviewers. Driver API: - Simplify locking in WiFi (cfg80211 and mac80211 layers), use wiphy mutex in most places and remove a lot of smaller locks. - Create a common DPLL configuration API. Allow configuring and querying state of PLL circuits used for clock syntonization, in network time distribution. - Unify fragmented and full page allocation APIs in page pool code. Let drivers be ignorant of PAGE_SIZE. - Rework PHY state machine to avoid races with calls to phy_stop(). - Notify DSA drivers of MAC address changes on user ports, improve correctness of offloads which depend on matching port MAC addresses. - Allow antenna control on injected WiFi frames. - Reduce the number of variants of napi_schedule(). - Simplify error handling when composing devlink health messages. Misc: - A lot of KCSAN data race "fixes", from Eric. - A lot of __counted_by() annotations, from Kees. - A lot of strncpy -> strscpy and printf format fixes. - Replace master/slave terminology with conduit/user in DSA drivers. - Handful of KUnit tests for netdev and WiFi core. Removed: - AppleTalk COPS. - AppleTalk ipddp. - TI AR7 CPMAC Ethernet driver. Drivers: - Ethernet high-speed NICs: - Intel (100G, ice, idpf): - add a driver for the Intel E2000 IPUs - make CRC/FCS stripping configurable - cross-timestamping for E823 devices - basic support for E830 devices - use aux-bus for managing client drivers - i40e: report firmware versions via devlink - nVidia/Mellanox: - support 4-port NICs - increase max number of channels to 256 - optimize / parallelize SF creation flow - Broadcom (bnxt): - enhance NIC temperature reporting - support PAM4 speeds and lane configuration - Marvell OcteonTX2: - PTP pulse-per-second output support - enable hardware timestamping for VFs - Solarflare/AMD: - conntrack NAT offload and offload for tunnels - Wangxun (ngbe/txgbe): - expose HW statistics - Pensando/AMD: - support PCI level reset - narrow down the condition under which skbs are linearized - Netronome/Corigine (nfp): - support CHACHA20-POLY1305 crypto in IPsec offload - Ethernet NICs embedded, slower, virtual: - Synopsys (stmmac): - add Loongson-1 SoC support - enable use of HW queues with no offload capabilities - enable PPS input support on all 5 channels - increase TX coalesce timer to 5ms - RealTek USB (r8152): improve efficiency of Rx by using GRO frags - xen: support SW packet timestamping - add drivers for implementations based on TI's PRUSS (AM64x EVM) - nVidia/Mellanox Ethernet datacenter switches: - avoid poor HW resource use on Spectrum-4 by better block selection for IPv6 multicast forwarding and ordering of blocks in ACL region - Ethernet embedded switches: - Microchip: - support configuring the drive strength for EMI compliance - ksz9477: partial ACL support - ksz9477: HSR offload - ksz9477: Wake on LAN - Realtek: - rtl8366rb: respect device tree config of the CPU port - Ethernet PHYs: - support Broadcom BCM5221 PHYs - TI dp83867: support hardware LED blinking - CAN: - add support for Linux-PHY based CAN transceivers - at91_can: clean up and use rx-offload helpers - WiFi: - MediaTek (mt76): - new sub-driver for mt7925 USB/PCIe devices - HW wireless <> Ethernet bridging in MT7988 chips - mt7603/mt7628 stability improvements - Qualcomm (ath12k): - WCN7850: - enable 320 MHz channels in 6 GHz band - hardware rfkill support - enable IEEE80211_HW_SINGLE_SCAN_ON_ALL_BANDS to make scan faster - read board data variant name from SMBIOS - QCN9274: mesh support - RealTek (rtw89): - TDMA-based multi-channel concurrency (MCC) - Silicon Labs (wfx): - Remain-On-Channel (ROC) support - Bluetooth: - ISO: many improvements for broadcast support - mark BCM4378/BCM4387 as BROKEN_LE_CODED - add support for QCA2066 - btmtksdio: enable Bluetooth wakeup from suspend" * tag 'net-next-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1816 commits) net: pcs: xpcs: Add 2500BASE-X case in get state for XPCS drivers net: bpf: Use sockopt_lock_sock() in ip_sock_set_tos() net: mana: Use xdp_set_features_flag instead of direct assignment vxlan: Cleanup IFLA_VXLAN_PORT_RANGE entry in vxlan_get_size() iavf: delete the iavf client interface iavf: add a common function for undoing the interrupt scheme iavf: use unregister_netdev iavf: rely on netdev's own registered state iavf: fix the waiting time for initial reset iavf: in iavf_down, don't queue watchdog_task if comms failed iavf: simplify mutex_trylock+sleep loops iavf: fix comments about old bit locks doc/netlink: Update schema to support cmd-cnt-name and cmd-max-name tools: ynl: introduce option to process unknown attributes or types ipvlan: properly track tx_errors netdevsim: Block until all devices are released nfp: using napi_build_skb() to replace build_skb() net: dsa: microchip: ksz9477: Fix spelling mistake "Enery" -> "Energy" net: dsa: microchip: Ensure Stable PME Pin State for Wake-on-LAN net: dsa: microchip: Refactor switch shutdown routine for WoL preparation ...
| * | posix-clock: introduce posix_clock_context conceptXabier Marquiegui2023-10-151-9/+27
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the necessary structure to support custom private-data per posix-clock user. The previous implementation of posix-clock assumed all file open instances need access to the same clock structure on private_data. The need for individual data structures per file open instance has been identified when developing support for multiple timestamp event queue users for ptp_clock. Signed-off-by: Xabier Marquiegui <reibax@gmail.com> Suggested-by: Richard Cochran <richardcochran@gmail.com> Suggested-by: Vinicius Costa Gomes <vinicius.gomes@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | alarmtimer: Use maximum alarm time for suspendGuenter Roeck2023-10-091-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some userspace applications use timerfd_create() to request wakeups after a long period of time. For example, a backup application may request a wakeup once per week. This is perfectly fine as long as the system does not try to suspend. However, if the system tries to suspend and the system's RTC does not support the required alarm timeout, the suspend operation will fail with an error such as rtc_cmos 00:01: Alarms can be up to one day in the future PM: dpm_run_callback(): platform_pm_suspend+0x0/0x4a returns -22 alarmtimer alarmtimer.4.auto: platform_pm_suspend+0x0/0x4a returned -22 after 117 usecs PM: Device alarmtimer.4.auto failed to suspend: error -22 This results in a refusal to suspend the system, causing substantial battery drain on affected systems. To fix the problem, use the maximum alarm time offset as reported by RTC drivers to set the maximum alarm time. While this may result in early wakeups from suspend, it is still much better than not suspending at all. Standardize system behavior if the requested alarm timeout is larger than the alarm timeout supported by the rtc chip. Currently, in this situation, the RTC driver will do one of the following: - It may return an error. - It may limit the alarm timeout to the maximum supported by the rtc chip. - It may mask the timeout by the maximum alarm timeout supported by the RTC chip (i.e. a requested timeout of 1 day + 1 minute may result in a 1 minute timeout). With this in place, if the RTC driver reports the maximum alarm timeout supported by the RTC chip, the system will always limit the alarm timeout to the maximum supported by the RTC chip. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/r/20230915152238.1144706-3-linux@roeck-us.net
* | tick/nohz: Update comments some moreIngo Molnar2023-09-291-76/+74
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Inspired by recent enhancements to comments in kernel/time/tick-sched.c, go through the entire file and fix/unify its comments: - Fix over a dozen typos, spelling mistakes & cases of bad grammar. - Re-phrase sentences that I needed to read three times to understand. [ I used the following arbitrary rule-of-thumb: - if I had to read a comment twice, it was usually my fault, - if I had to read it a third time, it was the comment's fault. ] - Comma updates: - Add commas where needed - Remove commas where not needed - In cases where a comma is optional, choose one variant and try to standardize it over similar sentences in the file. - Standardize on standalone 'NOHZ' spelling in free-flowing comments: s/nohz/NOHZ s/no idle tick/NOHZ Still keep 'dynticks' as a popular synonym. - Standardize on referring to variable names within free-flowing comments with the "'var'" nomenclature, and function names as "function_name()". - Standardize on '64-bit' and '32-bit': s/32bit/32-bit s/64bit/64-bit - Standardize on 'IRQ work': s/irq work/IRQ work - A few other tidyups I probably missed to list. No change in functionality intended - other than one small change to a syslog output string. Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/ZRVCNeMcSQcXS36N@gmail.com
* | tick/nohz: Don't shutdown the lowres tick from itselfFrederic Weisbecker2023-09-271-11/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In lowres dynticks mode, just like in highres dynticks mode, when there is no tick to program in the future, the tick eventually gets deactivated either: * From the idle loop if in idle mode. * From the IRQ exit if in full dynticks mode. Therefore there is no need to deactivate it from the tick itself. This just just brings more overhead in the idle tick path for no reason. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Link: https://lore.kernel.org/r/20230912104406.312185-4-frederic@kernel.org
* | tick/nohz: Update obsolete commentsFrederic Weisbecker2023-09-271-10/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | Some comments are obsolete enough to assume that IRQ exit restarts the tick in idle or RCU is turned on at the same time as the tick, among other details. Update them and add more. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230912104406.312185-3-frederic@kernel.org
* | tick/nohz: Rename the tick handlers to more self-explanatory namesFrederic Weisbecker2023-09-271-4/+4
|/ | | | | | | | | | The current names of the tick handlers don't tell much about what different between them. Use names that better reflect their role and resolution. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230912104406.312185-2-frederic@kernel.org
* Merge tag 'timers-urgent-2023-09-02' of ↵Linus Torvalds2023-09-021-1/+1
|\ | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Ingo Molnar: "Fix false positive 'softirq work is pending' messages on -rt kernels, caused by a buggy factoring-out of existing code" * tag 'timers-urgent-2023-09-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tick/rcu: Fix false positive "softirq work is pending" messages
| * tick/rcu: Fix false positive "softirq work is pending" messagesPaul Gortmaker2023-08-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit 0345691b24c0 ("tick/rcu: Stop allowing RCU_SOFTIRQ in idle") the new function report_idle_softirq() was created by breaking code out of the existing can_stop_idle_tick() for kernels v5.18 and newer. In doing so, the code essentially went from a one conditional: if (a && b && c) warn(); to a three conditional: if (!a) return; if (!b) return; if (!c) return; warn(); But that conversion got the condition for the RT specific local_bh_blocked() wrong. The original condition was: !local_bh_blocked() but the conversion failed to negate it so it ended up as: if (!local_bh_blocked()) return false; This issue lay dormant until another fixup for the same commit was added in commit a7e282c77785 ("tick/rcu: Fix bogus ratelimit condition"). This commit realized the ratelimit was essentially set to zero instead of ten, and hence *no* softirq pending messages would ever be issued. Once this commit was backported via linux-stable, both the v6.1 and v6.4 preempt-rt kernels started printing out 10 instances of this at boot: NOHZ tick-stop error: local softirq work is pending, handler #80!!! Remove the negation and return when local_bh_blocked() evaluates to true to bring the correct behaviour back. Fixes: 0345691b24c0 ("tick/rcu: Stop allowing RCU_SOFTIRQ in idle") Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Reviewed-by: Wen Yang <wenyang.linux@foxmail.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20230818200757.1808398-1-paul.gortmaker@windriver.com
* | Merge tag 'docs-6.6' of git://git.lwn.net/linuxLinus Torvalds2023-08-301-11/+158
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull documentation updates from Jonathan Corbet: "Documentation work keeps chugging along; this includes: - Work from Carlos Bilbao to integrate rustdoc output into the generated HTML documentation. This took some work to figure out how to do it without slowing the docs build and without creating people who don't have Rust installed, but Carlos got there - Move the loongarch and mips architecture documentation under Documentation/arch/ - Some more maintainer documentation from Jakub ... plus the usual assortment of updates, translations, and fixes" * tag 'docs-6.6' of git://git.lwn.net/linux: (56 commits) Docu: genericirq.rst: fix irq-example input: docs: pxrc: remove reference to phoenix-sim Documentation: serial-console: Fix literal block marker docs/mm: remove references to hmm_mirror ops and clean typos docs/zh_CN: correct regi_chg(),regi_add() to region_chg(),region_add() Documentation: Fix typos Documentation/ABI: Fix typos scripts: kernel-doc: fix macro handling in enums scripts: kernel-doc: parse DEFINE_DMA_UNMAP_[ADDR|LEN] Documentation: riscv: Update boot image header since EFI stub is supported Documentation: riscv: Add early boot document Documentation: arm: Add bootargs to the table of added DT parameters docs: kernel-parameters: Refer to the correct bitmap function doc: update params of memhp_default_state= docs: Add book to process/kernel-docs.rst docs: sparse: fix invalid link addresses docs: vfs: clean up after the iterate() removal docs: Add a section on surveys to the researcher guidelines docs: move mips under arch docs: move loongarch under arch ...
| * | time: add kernel-doc in time.cRandy Dunlap2023-07-141-11/+158
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | Add kernel-doc for all APIs that do not already have it. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: John Stultz <jstultz@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Stephen Boyd <sboyd@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Acked-by: John Stultz <jstultz@google.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20230704052405.5089-3-rdunlap@infradead.org
* | Merge tag 'linux-kselftest-kunit-6.6-rc1' of ↵Linus Torvalds2023-08-281-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull kunit updates from Shuah Khan: - add support for running Rust documentation tests as KUnit tests - make init, str, sync, types doctests compilable/testable - add support for attributes API which include speed, modules attributes, ability to filter and report attributes - add support for marking tests slow using attributes API - add attributes API documentation - fix a wild-memory-access bug in kunit_filter_suites() and a possible memory leak in kunit_filter_suites() - add support for counting number of test suites in a module, list action to kunit test modules, and test filtering on module tests * tag 'linux-kselftest-kunit-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (25 commits) kunit: fix struct kunit_attr header kunit: replace KUNIT_TRIGGER_STATIC_STUB maro with KUNIT_STATIC_STUB_REDIRECT kunit: Allow kunit test modules to use test filtering kunit: Make 'list' action available to kunit test modules kunit: Report the count of test suites in a module kunit: fix uninitialized variables bug in attributes filtering kunit: fix possible memory leak in kunit_filter_suites() kunit: fix wild-memory-access bug in kunit_filter_suites() kunit: Add documentation of KUnit test attributes kunit: add tests for filtering attributes kunit: time: Mark test as slow using test attributes kunit: memcpy: Mark tests as slow using test attributes kunit: tool: Add command line interface to filter and report attributes kunit: Add ability to filter attributes kunit: Add module attribute kunit: Add speed attribute kunit: Add test attributes API structure MAINTAINERS: add Rust KUnit files to the KUnit entry rust: support running Rust documentation tests as KUnit ones rust: types: make doctests compilable/testable ...
| * | kunit: time: Mark test as slow using test attributesRae Moar2023-07-261-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mark the time KUnit test, time64_to_tm_test_date_range, as slow using test attributes. This test ran relatively much slower than most other KUnit tests. By marking this test as slow, the test can now be filtered using the KUnit test attribute filtering feature. Example: --filter "speed>slow". This will run only the tests that have speeds faster than slow. The slow attribute will also be outputted in KTAP. Reviewed-by: David Gow <davidgow@google.com> Signed-off-by: Rae Moar <rmoar@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
* / clocksource: Handle negative skews in "skew is too large" messagesPaul E. McKenney2023-07-141-4/+4
|/ | | | | | | | | | | | | | The nanosecond-to-millisecond skew computation uses unsigned arithmetic, which produces user-unfriendly large positive numbers for negative skews. Therefore, use signed arithmetic for this computation in order to preserve the negativity. Reported-by: Chris Bainbridge <chris.bainbridge@gmail.com> Reported-by: Feng Tang <feng.tang@intel.com> Fixes: dd029269947a ("clocksource: Improve "skew is too large" messages") Reviewed-by: Feng Tang <feng.tang@intel.com> Tested-by: Chris Bainbridge <chris.bainbridge@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
* Merge tag 'hardening-v6.5-rc1' of ↵Linus Torvalds2023-06-271-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: "There are three areas of note: A bunch of strlcpy()->strscpy() conversions ended up living in my tree since they were either Acked by maintainers for me to carry, or got ignored for multiple weeks (and were trivial changes). The compiler option '-fstrict-flex-arrays=3' has been enabled globally, and has been in -next for the entire devel cycle. This changes compiler diagnostics (though mainly just -Warray-bounds which is disabled) and potential UBSAN_BOUNDS and FORTIFY _warning_ coverage. In other words, there are no new restrictions, just potentially new warnings. Any new FORTIFY warnings we've seen have been fixed (usually in their respective subsystem trees). For more details, see commit df8fc4e934c12b. The under-development compiler attribute __counted_by has been added so that we can start annotating flexible array members with their associated structure member that tracks the count of flexible array elements at run-time. It is possible (likely?) that the exact syntax of the attribute will change before it is finalized, but GCC and Clang are working together to sort it out. Any changes can be made to the macro while we continue to add annotations. As an example of that last case, I have a treewide commit waiting with such annotations found via Coccinelle: https://git.kernel.org/linus/adc5b3cb48a049563dc673f348eab7b6beba8a9b Also see commit dd06e72e68bcb4 for more details. Summary: - Fix KMSAN vs FORTIFY in strlcpy/strlcat (Alexander Potapenko) - Convert strreplace() to return string start (Andy Shevchenko) - Flexible array conversions (Arnd Bergmann, Wyes Karny, Kees Cook) - Add missing function prototypes seen with W=1 (Arnd Bergmann) - Fix strscpy() kerndoc typo (Arne Welzel) - Replace strlcpy() with strscpy() across many subsystems which were either Acked by respective maintainers or were trivial changes that went ignored for multiple weeks (Azeem Shaikh) - Remove unneeded cc-option test for UBSAN_TRAP (Nick Desaulniers) - Add KUnit tests for strcat()-family - Enable KUnit tests of FORTIFY wrappers under UML - Add more complete FORTIFY protections for strlcat() - Add missed disabling of FORTIFY for all arch purgatories. - Enable -fstrict-flex-arrays=3 globally - Tightening UBSAN_BOUNDS when using GCC - Improve checkpatch to check for strcpy, strncpy, and fake flex arrays - Improve use of const variables in FORTIFY - Add requested struct_size_t() helper for types not pointers - Add __counted_by macro for annotating flexible array size members" * tag 'hardening-v6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (54 commits) netfilter: ipset: Replace strlcpy with strscpy uml: Replace strlcpy with strscpy um: Use HOST_DIR for mrproper kallsyms: Replace all non-returning strlcpy with strscpy sh: Replace all non-returning strlcpy with strscpy of/flattree: Replace all non-returning strlcpy with strscpy sparc64: Replace all non-returning strlcpy with strscpy Hexagon: Replace all non-returning strlcpy with strscpy kobject: Use return value of strreplace() lib/string_helpers: Change returned value of the strreplace() jbd2: Avoid printing outside the boundary of the buffer checkpatch: Check for 0-length and 1-element arrays riscv/purgatory: Do not use fortified string functions s390/purgatory: Do not use fortified string functions x86/purgatory: Do not use fortified string functions acpi: Replace struct acpi_table_slit 1-element array with flex-array clocksource: Replace all non-returning strlcpy with strscpy string: use __builtin_memcpy() in strlcpy/strlcat staging: most: Replace all non-returning strlcpy with strscpy drm/i2c: tda998x: Replace all non-returning strlcpy with strscpy ...
| * clocksource: Replace all non-returning strlcpy with strscpyAzeem Shaikh2023-06-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | strlcpy() reads the entire source buffer first. This read may exceed the destination size limit. This is both inefficient and can lead to linear read overflows if a source string is not NUL-terminated [1]. In an effort to remove strlcpy() completely [2], replace strlcpy() here with strscpy(). No return values were used, so direct replacement is safe. [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy [2] https://github.com/KSPP/linux/issues/89 Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com> Acked-by: John Stultz <jstultz@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20230530163546.986188-1-azeemshaikh38@gmail.com
* | Merge tag 'sched-core-2023-06-27' of ↵Linus Torvalds2023-06-272-9/+19
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "Scheduler SMP load-balancer improvements: - Avoid unnecessary migrations within SMT domains on hybrid systems. Problem: On hybrid CPU systems, (processors with a mixture of higher-frequency SMT cores and lower-frequency non-SMT cores), under the old code lower-priority CPUs pulled tasks from the higher-priority cores if more than one SMT sibling was busy - resulting in many unnecessary task migrations. Solution: The new code improves the load balancer to recognize SMT cores with more than one busy sibling and allows lower-priority CPUs to pull tasks, which avoids superfluous migrations and lets lower-priority cores inspect all SMT siblings for the busiest queue. - Implement the 'runnable boosting' feature in the EAS balancer: consider CPU contention in frequency, EAS max util & load-balance busiest CPU selection. This improves CPU utilization for certain workloads, while leaves other key workloads unchanged. Scheduler infrastructure improvements: - Rewrite the scheduler topology setup code by consolidating it into the build_sched_topology() helper function and building it dynamically on the fly. - Resolve the local_clock() vs. noinstr complications by rewriting the code: provide separate sched_clock_noinstr() and local_clock_noinstr() functions to be used in instrumentation code, and make sure it is all instrumentation-safe. Fixes: - Fix a kthread_park() race with wait_woken() - Fix misc wait_task_inactive() bugs unearthed by the -rt merge: - Fix UP PREEMPT bug by unifying the SMP and UP implementations - Fix task_struct::saved_state handling - Fix various rq clock update bugs, unearthed by turning on the rq clock debugging code. - Fix the PSI WINDOW_MIN_US trigger limit, which was easy to trigger by creating enough cgroups, by removing the warnign and restricting window size triggers to PSI file write-permission or CAP_SYS_RESOURCE. - Propagate SMT flags in the topology when removing degenerate domain - Fix grub_reclaim() calculation bug in the deadline scheduler code - Avoid resetting the min update period when it is unnecessary, in psi_trigger_destroy(). - Don't balance a task to its current running CPU in load_balance(), which was possible on certain NUMA topologies with overlapping groups. - Fix the sched-debug printing of rq->nr_uninterruptible Cleanups: - Address various -Wmissing-prototype warnings, as a preparation to (maybe) enable this warning in the future. - Remove unused code - Mark more functions __init - Fix shadow-variable warnings" * tag 'sched-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits) sched/core: Avoid multiple calling update_rq_clock() in __cfsb_csd_unthrottle() sched/core: Avoid double calling update_rq_clock() in __balance_push_cpu_stop() sched/core: Fixed missing rq clock update before calling set_rq_offline() sched/deadline: Update GRUB description in the documentation sched/deadline: Fix bandwidth reclaim equation in GRUB sched/wait: Fix a kthread_park race with wait_woken() sched/topology: Mark set_sched_topology() __init sched/fair: Rename variable cpu_util eff_util arm64/arch_timer: Fix MMIO byteswap sched/fair, cpufreq: Introduce 'runnable boosting' sched/fair: Refactor CPU utilization functions cpuidle: Use local_clock_noinstr() sched/clock: Provide local_clock_noinstr() x86/tsc: Provide sched_clock_noinstr() clocksource: hyper-v: Provide noinstr sched_clock() clocksource: hyper-v: Adjust hv_read_tsc_page_tsc() to avoid special casing U64_MAX x86/vdso: Fix gettimeofday masking math64: Always inline u128 version of mul_u64_u64_shr() s390/time: Provide sched_clock_noinstr() loongarch: Provide noinstr sched_clock_read() ...
| * | time/sched_clock: Provide sched_clock_noinstr()Peter Zijlstra2023-06-051-6/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the intent to provide local_clock_noinstr(), a variant of local_clock() that's safe to be called from noinstr code (with the assumption that any such code will already be non-preemptible), prepare for things by providing a noinstr sched_clock_noinstr() function. Specifically, preempt_enable_*() calls out to schedule(), which upsets noinstr validation efforts. As such, pull out the preempt_{dis,en}able_notrace() requirements from the sched_clock_read() implementations by explicitly providing it in the sched_clock() function. This further requires said sched_clock_read() functions to be noinstr themselves, for ARCH_WANTS_NO_INSTR users. See the next few patches. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> # Hyper-V Link: https://lore.kernel.org/r/20230519102715.302350330@infradead.org
| * | seqlock/latch: Provide raw_read_seqcount_latch_retry()Peter Zijlstra2023-06-052-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The read side of seqcount_latch consists of: do { seq = raw_read_seqcount_latch(&latch->seq); ... } while (read_seqcount_latch_retry(&latch->seq, seq)); which is asymmetric in the raw_ department, and sure enough, read_seqcount_latch_retry() includes (explicit) instrumentation where raw_read_seqcount_latch() does not. This inconsistency becomes a problem when trying to use it from noinstr code. As such, fix it by renaming and re-implementing raw_read_seqcount_latch_retry() without the instrumentation. Specifically the instrumentation in question is kcsan_atomic_next(0) in do___read_seqcount_retry(). Loosing this annotation is not a problem because raw_read_seqcount_latch() does not pass through kcsan_atomic_next(KCSAN_SEQLOCK_REGION_MAX). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Tested-by: Michael Kelley <mikelley@microsoft.com> # Hyper-V Link: https://lore.kernel.org/r/20230519102715.233598176@infradead.org
* | | Merge tag 'timers-core-2023-06-26' of ↵Linus Torvalds2023-06-264-208/+326
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "Time, timekeeping and related device driver updates: Core: - A set of fixes, cleanups and enhancements to the posix timer code: - Prevent another possible live lock scenario in the exit() path, which affects POSIX_CPU_TIMERS_TASK_WORK enabled architectures. - Fix a loop termination issue which was reported syzcaller/KSAN in the posix timer ID allocation code. That triggered a deeper look into the posix-timer code which unearthed more small issues. - Add missing READ/WRITE_ONCE() annotations - Fix or remove completely outdated comments - Document places which are subtle and completely undocumented. - Add missing hrtimer modes to the trace event decoder - Small cleanups and enhancements all over the place Drivers: - Rework the Hyper-V clocksource and sched clock setup code - Remove a deprecated clocksource driver - Small fixes and enhancements all over the place" * tag 'timers-core-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits) clocksource/drivers/cadence-ttc: Fix memory leak in ttc_timer_probe dt-bindings: timers: Add Ralink SoCs timer clocksource/drivers/hyper-v: Rework clocksource and sched clock setup dt-bindings: timer: brcm,kona-timer: convert to YAML clocksource/drivers/imx-gpt: Fold <soc/imx/timer.h> into its only user clk: imx: Drop inclusion of unused header <soc/imx/timer.h> hrtimer: Add missing sparse annotations to hrtimer locking clocksource/drivers/imx-gpt: Use only a single name for functions clocksource/drivers/loongson1: Move PWM timer to clocksource framework dt-bindings: timer: Add Loongson-1 clocksource MIPS: Loongson32: Remove deprecated PWM timer clocksource clocksource/drivers/ingenic-timer: Use pm_sleep_ptr() macro tracing/timer: Add missing hrtimer modes to decode_hrtimer_mode(). posix-timers: Add sys_ni_posix_timers() prototype tick/rcu: Fix bogus ratelimit condition alarmtimer: Remove unnecessary (void *) cast alarmtimer: Remove unnecessary initialization of variable 'ret' posix-timers: Refer properly to CONFIG_HIGH_RES_TIMERS posix-timers: Polish coding style in a few places posix-timers: Remove pointless comments ...
| * | | hrtimer: Add missing sparse annotations to hrtimer lockingBen Dooks2023-06-221-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sparse warns about lock imbalance vs. the hrtimer_base lock due to missing sparse annotations: kernel/time/hrtimer.c:175:33: warning: context imbalance in 'lock_hrtimer_base' - wrong count at exit kernel/time/hrtimer.c:1301:28: warning: context imbalance in 'hrtimer_start_range_ns' - unexpected unlock kernel/time/hrtimer.c:1336:28: warning: context imbalance in 'hrtimer_try_to_cancel' - unexpected unlock kernel/time/hrtimer.c:1457:9: warning: context imbalance in '__hrtimer_get_remaining' - unexpected unlock Add the annotations to the relevant functions. Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230621075928.394481-1-ben.dooks@codethink.co.uk
| * | | tick/rcu: Fix bogus ratelimit conditionWen Yang2023-06-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ratelimit logic in report_idle_softirq() is broken because the exit condition is always true: static int ratelimit; if (ratelimit < 10) return false; ---> always returns here ratelimit++; ---> no chance to run Make it check for >= 10 instead. Fixes: 0345691b24c0 ("tick/rcu: Stop allowing RCU_SOFTIRQ in idle") Signed-off-by: Wen Yang <wenyang.linux@foxmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/tencent_5AAA3EEAB42095C9B7740BE62FBF9A67E007@qq.com
| * | | alarmtimer: Remove unnecessary (void *) castLi zeming2023-06-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pointers of type void * do not require a type cast when they are assigned to a real pointer. Signed-off-by: Li zeming <zeming@nfschina.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230609182059.4509-1-zeming@nfschina.com
| * | | alarmtimer: Remove unnecessary initialization of variable 'ret'Li zeming2023-06-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ret is assigned before checked, so it does not need to initialize the variable Signed-off-by: Li zeming <zeming@nfschina.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230609182856.4660-1-zeming@nfschina.com
| * | | posix-timers: Refer properly to CONFIG_HIGH_RES_TIMERSLukas Bulwahn2023-06-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit c78f261e5dcb ("posix-timers: Clarify posix_timer_fn() comments") turns an ifdef CONFIG_HIGH_RES_TIMERS into an conditional on "IS_ENABLED(CONFIG_HIGHRES_TIMERS)"; note that the new conditional refers to "HIGHRES_TIMERS" not "HIGH_RES_TIMERS" as before. Fix this typo introduced in that refactoring. Fixes: c78f261e5dcb ("posix-timers: Clarify posix_timer_fn() comments") Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230609094643.26253-1-lukas.bulwahn@gmail.com
| * | | posix-timers: Polish coding style in a few placesThomas Gleixner2023-06-181-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make it consistent with the TIP tree documentation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20230425183313.888493625@linutronix.de
| * | | posix-timers: Remove pointless commentsThomas Gleixner2023-06-181-25/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Documenting the obvious is just consuming space for no value. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20230425183313.832240451@linutronix.de
| * | | posix-timers: Clarify posix_timer_fn() commentsThomas Gleixner2023-06-181-30/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make the issues vs. SIG_IGN understandable and remove the 15 years old promise that a proper solution is already on the horizon. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/874jnrdmrq.ffs@tglx
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