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  1. 12 Oct, 2020 23 commits
  3. 11 Oct, 2020 10 commits
  5. 10 Oct, 2020 6 commits
    • Linus Torvalds's avatar
      Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux · da690031
      Linus Torvalds authored 
      Pull i2c fixes from Wolfram Sang:
 "Some more driver bugfixes for I2C. Including a revert - the updated
  series for it will come during the next merge window"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: owl: Clear NACK and BUS error bits
  Revert "i2c: imx: Fix reset of I2SR_IAL flag"
  i2c: meson: fixup rate calculation with filter delay
  i2c: meson: keep peripheral clock enabled
  i2c: meson: fix clock setting overwrite
  i2c: imx: Fix reset of I2SR_IAL flag
      da690031
    • Vladimir Zapolskiy's avatar
      cifs: Fix incomplete memory allocation on setxattr path · 64b7f674
      Vladimir Zapolskiy authored 
      On setxattr() syscall path due to an apprent typo the size of a dynamically
allocated memory chunk for storing struct smb2_file_full_ea_info object is
computed incorrectly, to be more precise the first addend is the size of
a pointer instead of the wanted object size. Coincidentally it makes no
difference on 64-bit platforms, however on 32-bit targets the following
memcpy() writes 4 bytes of data outside of the dynamically allocated memory.

  =============================================================================
  BUG kmalloc-16 (Not tainted): Redzone overwritten
  -----------------------------------------------------------------------------

  Disabling lock debugging due to kernel taint
  INFO: 0x79e69a6f-0x9e5cdecf @offset=368. First byte 0x73 instead of 0xcc
  INFO: Slab 0xd36d2454 objects=85 used=51 fp=0xf7d0fc7a flags=0x35000201
  INFO: Object 0x6f171df3 @offset=352 fp=0x00000000

  Redzone 5d4ff02d: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc  ................
  Object 6f171df3: 00 00 00 00 00 05 06 00 73 6e 72 75 62 00 66 69  ........snrub.fi
  Redzone 79e69a6f: 73 68 32 0a                                      sh2.
  Padding 56254d82: 5a 5a 5a 5a 5a 5a 5a 5a                          ZZZZZZZZ
  CPU: 0 PID: 8196 Comm: attr Tainted: G    B             5.9.0-rc8+ #3
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1 04/01/2014
  Call Trace:
   dump_stack+0x54/0x6e
   print_trailer+0x12c/0x134
   check_bytes_and_report.cold+0x3e/0x69
   check_object+0x18c/0x250
   free_debug_processing+0xfe/0x230
   __slab_free+0x1c0/0x300
   kfree+0x1d3/0x220
   smb2_set_ea+0x27d/0x540
   cifs_xattr_set+0x57f/0x620
   __vfs_setxattr+0x4e/0x60
   __vfs_setxattr_noperm+0x4e/0x100
   __vfs_setxattr_locked+0xae/0xd0
   vfs_setxattr+0x4e/0xe0
   setxattr+0x12c/0x1a0
   path_setxattr+0xa4/0xc0
   __ia32_sys_lsetxattr+0x1d/0x20
   __do_fast_syscall_32+0x40/0x70
   do_fast_syscall_32+0x29/0x60
   do_SYSENTER_32+0x15/0x20
   entry_SYSENTER_32+0x9f/0xf2

Fixes: 5517554e ("cifs: Add support for writing attributes on SMB2+")
Signed-off-by: default avatarVladimir Zapolskiy <vladimir@tuxera.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      64b7f674
    • Hugh Dickins's avatar
      mm/khugepaged: fix filemap page_to_pgoff(page) != offset · 033b5d77
      Hugh Dickins authored 
      There have been elusive reports of filemap_fault() hitting its
VM_BUG_ON_PAGE(page_to_pgoff(page) != offset, page) on kernels built
with CONFIG_READ_ONLY_THP_FOR_FS=y.

Suren has hit it on a kernel with CONFIG_READ_ONLY_THP_FOR_FS=y and
CONFIG_NUMA is not set: and he has analyzed it down to how khugepaged
without NUMA reuses the same huge page after collapse_file() failed
(whereas NUMA targets its allocation to the respective node each time).
And most of us were usually testing with CONFIG_NUMA=y kernels.

collapse_file(old start)
  new_page = khugepaged_alloc_page(hpage)
  __SetPageLocked(new_page)
  new_page->index = start // hpage->index=old offset
  new_page->mapping = mapping
  xas_store(&xas, new_page)

                          filemap_fault
                            page = find_get_page(mapping, offset)
                            // if offset falls inside hpage then
                            // compound_head(page) == hpage
                            lock_page_maybe_drop_mmap()
                              __lock_page(page)

  // collapse fails
  xas_store(&xas, old page)
  new_page->mapping = NULL
  unlock_page(new_page)

collapse_file(new start)
  new_page = khugepaged_alloc_page(hpage)
  __SetPageLocked(new_page)
  new_page->index = start // hpage->index=new offset
  new_page->mapping = mapping // mapping becomes valid again

                            // since compound_head(page) == hpage
                            // page_to_pgoff(page) got changed
                            VM_BUG_ON_PAGE(page_to_pgoff(page) != offset)

An initial patch replaced __SetPageLocked() by lock_page(), which did
fix the race which Suren illustrates above.  But testing showed that it's
not good enough: if the racing task's __lock_page() gets delayed long
after its find_get_page(), then it may follow collapse_file(new start)'s
successful final unlock_page(), and crash on the same VM_BUG_ON_PAGE.

It could be fixed by relaxing filemap_fault()'s VM_BUG_ON_PAGE to a
check and retry (as is done for mapping), with similar relaxations in
find_lock_entry() and pagecache_get_page(): but it's not obvious what
else might get caught out; and khugepaged non-NUMA appears to be unique
in exposing a page to page cache, then revoking, without going through
a full cycle of freeing before reuse.

Instead, non-NUMA khugepaged_prealloc_page() release the old page
if anyone else has a reference to it (1% of cases when I tested).

Although never reported on huge tmpfs, I believe its find_lock_entry()
has been at similar risk; but huge tmpfs does not rely on khugepaged
for its normal working nearly so much as READ_ONLY_THP_FOR_FS does.
Reported-by: default avatarDenis Lisov <dennis.lissov@gmail.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=206569
Link: https://lore.kernel.org/linux-mm/?q=20200219144635.3b7417145de19b65f258c943%40linux-foundation.orgReported-by: default avatarQian Cai <cai@lca.pw>
Link: https://lore.kernel.org/linux-xfs/?q=20200616013309.GB815%40lca.pwReported-and-analyzed-by: default avatarSuren Baghdasaryan <surenb@google.com>
Fixes: 87c460a0 ("mm/khugepaged: collapse_shmem() without freezing new_page")
Signed-off-by: default avatarHugh Dickins <hughd@google.com>
Cc: stable@vger.kernel.org # v4.9+
Reviewed-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      033b5d77
    • Cristian Ciocaltea's avatar
      i2c: owl: Clear NACK and BUS error bits · f5b3f433
      Cristian Ciocaltea authored 
      When the NACK and BUS error bits are set by the hardware, the driver is
responsible for clearing them by writing "1" into the corresponding
status registers.

Hence perform the necessary operations in owl_i2c_interrupt().

Fixes: d211e62a ("i2c: Add Actions Semiconductor Owl family S900 I2C driver")
Reported-by: default avatarManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: default avatarCristian Ciocaltea <cristian.ciocaltea@gmail.com>
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
      f5b3f433
    • Wolfram Sang's avatar
      Revert "i2c: imx: Fix reset of I2SR_IAL flag" · 5a02e7c4
      Wolfram Sang authored 
      This reverts commit fa4d3055. An updated
version was sent. So, revert this version and give the new version more
time for testing.
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
      5a02e7c4
    • Linus Torvalds's avatar
      Merge tag 'spi-fix-v5.9-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi · 6f2f486d
      Linus Torvalds authored 
      Pull spi fix from Mark Brown:
 "One last minute fix for v5.9 which has been causing crashes in test
  systems with the fsl-dspi driver when they hit deferred probe (and
  which I probably let cook in next a bit longer than is ideal).

  And an update to MAINTAINERS reflecting Serge's extensive and
  detailed recent work on the DesignWare driver"

* tag 'spi-fix-v5.9-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  MAINTAINERS: Add maintainer of DW APB SSI driver
  spi: fsl-dspi: fix NULL pointer dereference
      6f2f486d
  7. 09 Oct, 2020 1 commit
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