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  1. 18 Jun, 2021 4 commits
    • Steven Rostedt (VMware)'s avatar
      tracing: Do no increment trace_clock_global() by one · 89529d8b
      Steven Rostedt (VMware) authored 
      The trace_clock_global() tries to make sure the events between CPUs is
somewhat in order. A global value is used and updated by the latest read
of a clock. If one CPU is ahead by a little, and is read by another CPU, a
lock is taken, and if the timestamp of the other CPU is behind, it will
simply use the other CPUs timestamp.

The lock is also only taken with a "trylock" due to tracing, and strange
recursions can happen. The lock is not taken at all in NMI context.

In the case where the lock is not able to be taken, the non synced
timestamp is returned. But it will not be less than the saved global
timestamp.

The problem arises because when the time goes "backwards" the time
returned is the saved timestamp plus 1. If the lock is not taken, and the
plus one to the timestamp is returned, there's a small race that can cause
the time to go backwards!

	CPU0				CPU1
	----				----
				trace_clock_global() {
				    ts = clock() [ 1000 ]
				    trylock(clock_lock) [ success ]
				    global_ts = ts; [ 1000 ]

				    <interrupted by NMI>
 trace_clock_global() {
    ts = clock() [ 999 ]
    if (ts < global_ts)
	ts = global_ts + 1 [ 1001 ]

    trylock(clock_lock) [ fail ]

    return ts [ 1001]
 }
				    unlock(clock_lock);
				    return ts; [ 1000 ]
				}

 trace_clock_global() {
    ts = clock() [ 1000 ]
    if (ts < global_ts) [ false 1000 == 1000 ]

    trylock(clock_lock) [ success ]
    global_ts = ts; [ 1000 ]
    unlock(clock_lock)

    return ts; [ 1000 ]
 }

The above case shows to reads of trace_clock_global() on the same CPU, but
the second read returns one less than the first read. That is, time when
backwards, and this is not what is allowed by trace_clock_global().

This was triggered by heavy tracing and the ring buffer checker that tests
for the clock going backwards:

 Ring buffer clock went backwards: 20613921464 -> 20613921463
 ------------[ cut here ]------------
 WARNING: CPU: 2 PID: 0 at kernel/trace/ring_buffer.c:3412 check_buffer+0x1b9/0x1c0
 Modules linked in:
 [..]
 [CPU: 2]TIME DOES NOT MATCH expected:20620711698 actual:20620711697 delta:6790234 before:20613921463 after:20613921463
   [20613915818] PAGE TIME STAMP
   [20613915818] delta:0
   [20613915819] delta:1
   [20613916035] delta:216
   [20613916465] delta:430
   [20613916575] delta:110
   [20613916749] delta:174
   [20613917248] delta:499
   [20613917333] delta:85
   [20613917775] delta:442
   [20613917921] delta:146
   [20613918321] delta:400
   [20613918568] delta:247
   [20613918768] delta:200
   [20613919306] delta:538
   [20613919353] delta:47
   [20613919980] delta:627
   [20613920296] delta:316
   [20613920571] delta:275
   [20613920862] delta:291
   [20613921152] delta:290
   [20613921464] delta:312
   [20613921464] delta:0 TIME EXTEND
   [20613921464] delta:0

This happened more than once, and always for an off by one result. It also
started happening after commit aafe104a was added.

Cc: stable@vger.kernel.org
Fixes: aafe104a ("tracing: Restructure trace_clock_global() to never block")
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      89529d8b
    • Steven Rostedt (VMware)'s avatar
      tracing: Do not stop recording comms if the trace file is being read · 4fdd595e
      Steven Rostedt (VMware) authored 
      A while ago, when the "trace" file was opened, tracing was stopped, and
code was added to stop recording the comms to saved_cmdlines, for mapping
of the pids to the task name.

Code has been added that only records the comm if a trace event occurred,
and there's no reason to not trace it if the trace file is opened.

Cc: stable@vger.kernel.org
Fixes: 7ffbd48d ("tracing: Cache comms only after an event occurred")
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      4fdd595e
    • Steven Rostedt (VMware)'s avatar
      tracing: Do not stop recording cmdlines when tracing is off · 85550c83
      Steven Rostedt (VMware) authored 
      The saved_cmdlines is used to map pids to the task name, such that the
output of the tracing does not just show pids, but also gives a human
readable name for the task.

If the name is not mapped, the output looks like this:

    <...>-1316          [005] ...2   132.044039: ...

Instead of this:

    gnome-shell-1316    [005] ...2   132.044039: ...

The names are updated when tracing is running, but are skipped if tracing
is stopped. Unfortunately, this stops the recording of the names if the
top level tracer is stopped, and not if there's other tracers active.

The recording of a name only happens when a new event is written into a
ring buffer, so there is no need to test if tracing is on or not. If
tracing is off, then no event is written and no need to test if tracing is
off or not.

Remove the check, as it hides the names of tasks for events in the
instance buffers.

Cc: stable@vger.kernel.org
Fixes: 7ffbd48d ("tracing: Cache comms only after an event occurred")
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      85550c83
    • Peter Zijlstra's avatar
      recordmcount: Correct st_shndx handling · fb780761
      Peter Zijlstra authored 
      One should only use st_shndx when >SHN_UNDEF and <SHN_LORESERVE. When
SHN_XINDEX, then use .symtab_shndx. Otherwise use 0.

This handles the case: st_shndx >= SHN_LORESERVE && st_shndx != SHN_XINDEX.

Link: https://lore.kernel.org/lkml/20210607023839.26387-1-mark-pk.tsai@mediatek.com/
Link: https://lkml.kernel.org/r/20210616154126.2794-1-mark-pk.tsai@mediatek.comReported-by: default avatarMark-PK Tsai <mark-pk.tsai@mediatek.com>
Tested-by: default avatarMark-PK Tsai <mark-pk.tsai@mediatek.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
[handle endianness of sym->st_shndx]
Signed-off-by: default avatarMark-PK Tsai <mark-pk.tsai@mediatek.com>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      fb780761
  3. 08 Jun, 2021 4 commits
  5. 06 Jun, 2021 11 commits
    • Linus Torvalds's avatar
      Linux 5.13-rc5 · 614124be
      Linus Torvalds authored
      614124be
    • Linus Torvalds's avatar
      Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi · 90d56a3d
      Linus Torvalds authored 
      Pull SCSI fixes from James Bottomley:
 "Five small and fairly minor fixes, all in drivers"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: scsi_devinfo: Add blacklist entry for HPE OPEN-V
  scsi: ufs: ufs-mediatek: Fix HCI version in some platforms
  scsi: qedf: Do not put host in qedf_vport_create() unconditionally
  scsi: lpfc: Fix failure to transmit ABTS on FC link
  scsi: target: core: Fix warning on realtime kernels
      90d56a3d
    • Linus Torvalds's avatar
      Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 · 20e41d9b
      Linus Torvalds authored 
      Pull ext4 fixes from Ted Ts'o:
 "Miscellaneous ext4 bug fixes"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: Only advertise encrypted_casefold when encryption and unicode are enabled
  ext4: fix no-key deletion for encrypt+casefold
  ext4: fix memory leak in ext4_fill_super
  ext4: fix fast commit alignment issues
  ext4: fix bug on in ext4_es_cache_extent as ext4_split_extent_at failed
  ext4: fix accessing uninit percpu counter variable with fast_commit
  ext4: fix memory leak in ext4_mb_init_backend on error path.
      20e41d9b
    • Linus Torvalds's avatar
      Merge tag 'arm-soc-fixes-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc · decad3e1
      Linus Torvalds authored 
      Pull ARM SoC fixes from Olof Johansson:
 "A set of fixes that have been coming in over the last few weeks, the
  usual mix of fixes:

   - DT fixups for TI K3

   - SATA drive detection fix for TI DRA7

   - Power management fixes and a few build warning removals for OMAP

   - OP-TEE fix to use standard API for UUID exporting

   - DT fixes for a handful of i.MX boards

  And a few other smaller items"

* tag 'arm-soc-fixes-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (29 commits)
  arm64: meson: select COMMON_CLK
  soc: amlogic: meson-clk-measure: remove redundant dev_err call in meson_msr_probe()
  ARM: OMAP1: ams-delta: remove unused function ams_delta_camera_power
  bus: ti-sysc: Fix flakey idling of uarts and stop using swsup_sidle_act
  ARM: dts: imx: emcon-avari: Fix nxp,pca8574 #gpio-cells
  ARM: dts: imx7d-pico: Fix the 'tuning-step' property
  ARM: dts: imx7d-meerkat96: Fix the 'tuning-step' property
  arm64: dts: freescale: sl28: var1: fix RGMII clock and voltage
  arm64: dts: freescale: sl28: var4: fix RGMII clock and voltage
  ARM: imx: pm-imx27: Include "common.h"
  arm64: dts: zii-ultra: fix 12V_MAIN voltage
  arm64: dts: zii-ultra: remove second GEN_3V3 regulator instance
  arm64: dts: ls1028a: fix memory node
  bus: ti-sysc: Fix am335x resume hang for usb otg module
  ARM: OMAP2+: Fix build warning when mmc_omap is not built
  ARM: OMAP1: isp1301-omap: Add missing gpiod_add_lookup_table function
  ARM: OMAP1: Fix use of possibly uninitialized irq variable
  optee: use export_uuid() to copy client UUID
  arm64: dts: ti: k3*: Introduce reg definition for interrupt routers
  arm64: dts: ti: k3-am65|j721e|am64: Map the dma / navigator subsystem via explicit ranges
  ...
      decad3e1
    • Linus Torvalds's avatar
      Merge tag 'powerpc-5.13-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux · bd7b12aa
      Linus Torvalds authored 
      Pull powerpc fixes from Michael Ellerman:
 "Fix our KVM reverse map real-mode handling since we enabled huge
  vmalloc (in some configurations).

  Revert a recent change to our IOMMU code which broke some devices.

  Fix KVM handling of FSCR on P7/P8, which could have possibly let a
  guest crash it's Qemu.

  Fix kprobes validation of prefixed instructions across page boundary.

  Thanks to Alexey Kardashevskiy, Christophe Leroy, Fabiano Rosas,
  Frederic Barrat, Naveen N. Rao, and Nicholas Piggin"

* tag 'powerpc-5.13-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  Revert "powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs"
  KVM: PPC: Book3S HV: Save host FSCR in the P7/8 path
  powerpc: Fix reverse map real-mode address lookup with huge vmalloc
  powerpc/kprobes: Fix validation of prefixed instructions across page boundary
      bd7b12aa
    • Linus Torvalds's avatar
      Merge tag 'x86_urgent_for_v5.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 773ac53b
      Linus Torvalds authored 
      Pull x86 fixes from Borislav Petkov:
 "A bunch of x86/urgent stuff accumulated for the last two weeks so
  lemme unload it to you.

  It should be all totally risk-free, of course. :-)

   - Fix out-of-spec hardware (1st gen Hygon) which does not implement
     MSR_AMD64_SEV even though the spec clearly states so, and check
     CPUID bits first.

   - Send only one signal to a task when it is a SEGV_PKUERR si_code
     type.

   - Do away with all the wankery of reserving X amount of memory in the
     first megabyte to prevent BIOS corrupting it and simply and
     unconditionally reserve the whole first megabyte.

   - Make alternatives NOP optimization work at an arbitrary position
     within the patched sequence because the compiler can put
     single-byte NOPs for alignment anywhere in the sequence (32-bit
     retpoline), vs our previous assumption that the NOPs are only
     appended.

   - Force-disable ENQCMD[S] instructions support and remove
     update_pasid() because of insufficient protection against FPU state
     modification in an interrupt context, among other xstate horrors
     which are being addressed at the moment. This one limits the
     fallout until proper enablement.

   - Use cpu_feature_enabled() in the idxd driver so that it can be
     build-time disabled through the defines in disabled-features.h.

   - Fix LVT thermal setup for SMI delivery mode by making sure the APIC
     LVT value is read before APIC initialization so that softlockups
     during boot do not happen at least on one machine.

   - Mark all legacy interrupts as legacy vectors when the IO-APIC is
     disabled and when all legacy interrupts are routed through the PIC"

* tag 'x86_urgent_for_v5.13-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sev: Check SME/SEV support in CPUID first
  x86/fault: Don't send SIGSEGV twice on SEGV_PKUERR
  x86/setup: Always reserve the first 1M of RAM
  x86/alternative: Optimize single-byte NOPs at an arbitrary position
  x86/cpufeatures: Force disable X86_FEATURE_ENQCMD and remove update_pasid()
  dmaengine: idxd: Use cpu_feature_enabled()
  x86/thermal: Fix LVT thermal setup for SMI delivery mode
  x86/apic: Mark _all_ legacy interrupts when IO/APIC is missing
      773ac53b
    • Daniel Rosenberg's avatar
      ext4: Only advertise encrypted_casefold when encryption and unicode are enabled · e71f99f2
      Daniel Rosenberg authored 
      Encrypted casefolding is only supported when both encryption and
casefolding are both enabled in the config.

Fixes: 471fbbea ("ext4: handle casefolding with encryption")
Cc: stable@vger.kernel.org # 5.13+
Signed-off-by: default avatarDaniel Rosenberg <drosen@google.com>
Link: https://lore.kernel.org/r/20210603094849.314342-1-drosen@google.comSigned-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      e71f99f2
    • Daniel Rosenberg's avatar
      ext4: fix no-key deletion for encrypt+casefold · 63e7f128
      Daniel Rosenberg authored 
      commit 471fbbea ("ext4: handle casefolding with encryption") is
missing a few checks for the encryption key which are needed to
support deleting enrypted casefolded files when the key is not
present.

This bug made it impossible to delete encrypted+casefolded directories
without the encryption key, due to errors like:

    W         : EXT4-fs warning (device vdc): __ext4fs_dirhash:270: inode #49202: comm Binder:378_4: Siphash requires key

Repro steps in kvm-xfstests test appliance:
      mkfs.ext4 -F -E encoding=utf8 -O encrypt /dev/vdc
      mount /vdc
      mkdir /vdc/dir
      chattr +F /vdc/dir
      keyid=$(head -c 64 /dev/zero | xfs_io -c add_enckey /vdc | awk '{print $NF}')
      xfs_io -c "set_encpolicy $keyid" /vdc/dir
      for i in `seq 1 100`; do
          mkdir /vdc/dir/$i
      done
      xfs_io -c "rm_enckey $keyid" /vdc
      rm -rf /vdc/dir # fails with the bug

Fixes: 471fbbea ("ext4: handle casefolding with encryption")
Signed-off-by: default avatarDaniel Rosenberg <drosen@google.com>
Link: https://lore.kernel.org/r/20210522004132.2142563-1-drosen@google.comSigned-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      63e7f128
    • Alexey Makhalov's avatar
      ext4: fix memory leak in ext4_fill_super · afd09b61
      Alexey Makhalov authored 
      Buffer head references must be released before calling kill_bdev();
otherwise the buffer head (and its page referenced by b_data) will not
be freed by kill_bdev, and subsequently that bh will be leaked.

If blocksizes differ, sb_set_blocksize() will kill current buffers and
page cache by using kill_bdev(). And then super block will be reread
again but using correct blocksize this time. sb_set_blocksize() didn't
fully free superblock page and buffer head, and being busy, they were
not freed and instead leaked.

This can easily be reproduced by calling an infinite loop of:

  systemctl start <ext4_on_lvm>.mount, and
  systemctl stop <ext4_on_lvm>.mount

... since systemd creates a cgroup for each slice which it mounts, and
the bh leak get amplified by a dying memory cgroup that also never
gets freed, and memory consumption is much more easily noticed.

Fixes: ce40733c ("ext4: Check for return value from sb_set_blocksize")
Fixes: ac27a0ec ("ext4: initial copy of files from ext3")
Link: https://lore.kernel.org/r/20210521075533.95732-1-amakhalov@vmware.comSigned-off-by: default avatarAlexey Makhalov <amakhalov@vmware.com>
Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
      afd09b61
    • Harshad Shirwadkar's avatar
      ext4: fix fast commit alignment issues · a7ba36bc
      Harshad Shirwadkar authored 
      Fast commit recovery data on disk may not be aligned. So, when the
recovery code reads it, this patch makes sure that fast commit info
found on-disk is first memcpy-ed into an aligned variable before
accessing it. As a consequence of it, we also remove some macros that
could resulted in unaligned accesses.

Cc: stable@kernel.org
Fixes: 8016e29f ("ext4: fast commit recovery path")
Signed-off-by: default avatarHarshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20210519215920.2037527-1-harshads@google.comSigned-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      a7ba36bc
    • Ye Bin's avatar
      ext4: fix bug on in ext4_es_cache_extent as ext4_split_extent_at failed · 082cd4ec
      Ye Bin authored 
      We got follow bug_on when run fsstress with injecting IO fault:
[130747.323114] kernel BUG at fs/ext4/extents_status.c:762!
[130747.323117] Internal error: Oops - BUG: 0 [#1] SMP
......
[130747.334329] Call trace:
[130747.334553]  ext4_es_cache_extent+0x150/0x168 [ext4]
[130747.334975]  ext4_cache_extents+0x64/0xe8 [ext4]
[130747.335368]  ext4_find_extent+0x300/0x330 [ext4]
[130747.335759]  ext4_ext_map_blocks+0x74/0x1178 [ext4]
[130747.336179]  ext4_map_blocks+0x2f4/0x5f0 [ext4]
[130747.336567]  ext4_mpage_readpages+0x4a8/0x7a8 [ext4]
[130747.336995]  ext4_readpage+0x54/0x100 [ext4]
[130747.337359]  generic_file_buffered_read+0x410/0xae8
[130747.337767]  generic_file_read_iter+0x114/0x190
[130747.338152]  ext4_file_read_iter+0x5c/0x140 [ext4]
[130747.338556]  __vfs_read+0x11c/0x188
[130747.338851]  vfs_read+0x94/0x150
[130747.339110]  ksys_read+0x74/0xf0

This patch's modification is according to Jan Kara's suggestion in:
https://patchwork.ozlabs.org/project/linux-ext4/patch/20210428085158.3728201-1-yebin10@huawei.com/
"I see. Now I understand your patch. Honestly, seeing how fragile is trying
to fix extent tree after split has failed in the middle, I would probably
go even further and make sure we fix the tree properly in case of ENOSPC
and EDQUOT (those are easily user triggerable).  Anything else indicates a
HW problem or fs corruption so I'd rather leave the extent tree as is and
don't try to fix it (which also means we will not create overlapping
extents)."

Cc: stable@kernel.org
Signed-off-by: default avatarYe Bin <yebin10@huawei.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210506141042.3298679-1-yebin10@huawei.comSigned-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      082cd4ec
  7. 05 Jun, 2021 21 commits
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