1. 18 Feb, 2024 3 commits
  2. 13 Feb, 2024 1 commit
  3. 31 Jan, 2024 1 commit
  4. 22 Jan, 2024 4 commits
  5. 19 Jan, 2024 1 commit
    • Heiko Carstens's avatar
      tick-sched: Fix idle and iowait sleeptime accounting vs CPU hotplug · 71fee48f
      Heiko Carstens authored
      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 4b0c0f29
      ("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 be76ea61 ("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: 4b0c0f29 ("tick: Cleanup NOHZ per cpu data on cpu down")
      Reported-by: default avatarGerald Schaefer <gerald.schaefer@linux.ibm.com>
      Signed-off-by: default avatarHeiko Carstens <hca@linux.ibm.com>
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Reviewed-by: default avatarFrederic Weisbecker <frederic@kernel.org>
      Link: https://lore.kernel.org/r/20240115163555.1004144-1-hca@linux.ibm.com
      71fee48f
  6. 18 Jan, 2024 1 commit
  7. 27 Dec, 2023 6 commits
  8. 20 Dec, 2023 12 commits
  9. 22 Nov, 2023 1 commit
  10. 19 Nov, 2023 8 commits
  11. 18 Nov, 2023 2 commits
    • Linus Torvalds's avatar
      Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi · 037266a5
      Linus Torvalds authored
      Pull SCSI fixes from James Bottomley:
       "Seven small fixes, six in drivers and one in sd.
      
        The sd fix is so large because it changes a struct pointer to a struct
        but otherwise is fairly simple"
      
      * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
        scsi: ufs: qcom-ufs: dt-bindings: Document the SM8650 UFS Controller
        scsi: sd: Fix sshdr use in sd_suspend_common()
        scsi: scsi_debug: Delete some bogus error checking
        scsi: scsi_debug: Fix some bugs in sdebug_error_write()
        scsi: ufs: core: Fix racing issue between ufshcd_mcq_abort() and ISR
        scsi: ufs: core: Expand MCQ queue slot to DeviceQueueDepth + 1
        scsi: qla2xxx: Fix system crash due to bad pointer access
      037266a5
    • Linus Torvalds's avatar
      Merge tag 'parisc-for-6.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux · 2254005e
      Linus Torvalds authored
      Pull parisc fixes from Helge Deller:
       "On parisc we still sometimes need writeable stacks, e.g. if programs
        aren't compiled with gcc-14. To avoid issues with the upcoming
        systemd-254 we therefore have to disable prctl(PR_SET_MDWE) for now
        (for parisc only).
      
        The other two patches are minor: a bugfix for the soft power-off on
        qemu with 64-bit kernel and prefer strscpy() over strlcpy():
      
         - Fix power soft-off on qemu
      
         - Disable prctl(PR_SET_MDWE) since parisc sometimes still needs
           writeable stacks
      
         - Use strscpy instead of strlcpy in show_cpuinfo()"
      
      * tag 'parisc-for-6.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
        prctl: Disable prctl(PR_SET_MDWE) on parisc
        parisc/power: Fix power soft-off when running on qemu
        parisc: Replace strlcpy() with strscpy()
      2254005e