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Dan writes:
"libnvdimm/dax 4.19-rc8
* Fix a livelock in dax_layout_busy_page() present since v4.18. The
lockup triggers when truncating an actively mapped huge page out of
a mapping pinned for direct-I/O.
* Fix mprotect() clobbers of _PAGE_DEVMAP. Broken since v4.5
mprotect() clears this flag that is needed to communicate the
liveness of device pages to the get_user_pages() path."
* tag 'libnvdimm-fixes-4.19-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
mm: Preserve _PAGE_DEVMAP across mprotect() calls
filesystem-dax: Fix dax_layout_busy_page() livelock
Wolfram writes:
"i2c fix for 4.19:
I2C has one documentation bugfix for something we changed during the
v4.19 cycle"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: Fix kerneldoc for renamed i2c dma put function
Currently _PAGE_DEVMAP bit is not preserved in mprotect(2) calls. As a
result we will see warnings such as:
BUG: Bad page map in process JobWrk0013 pte:800001803875ea25 pmd:7624381067
addr:00007f0930720000 vm_flags:280000f9 anon_vma: (null) mapping:ffff97f2384056f0 index:0
file:457-000000fe00000030-00000009-000000ca-00000001_2001.fileblock fault:xfs_filemap_fault [xfs] mmap:xfs_file_mmap [xfs] readpage: (null)
CPU: 3 PID: 15848 Comm: JobWrk0013 Tainted: G W 4.12.14-2.g7573215-default #1 SLE12-SP4 (unreleased)
Hardware name: Intel Corporation S2600WFD/S2600WFD, BIOS SE5C620.86B.01.00.0833.051120182255 05/11/2018
Call Trace:
dump_stack+0x5a/0x75
print_bad_pte+0x217/0x2c0
? enqueue_task_fair+0x76/0x9f0
_vm_normal_page+0xe5/0x100
zap_pte_range+0x148/0x740
unmap_page_range+0x39a/0x4b0
unmap_vmas+0x42/0x90
unmap_region+0x99/0xf0
? vma_gap_callbacks_rotate+0x1a/0x20
do_munmap+0x255/0x3a0
vm_munmap+0x54/0x80
SyS_munmap+0x1d/0x30
do_syscall_64+0x74/0x150
entry_SYSCALL_64_after_hwframe+0x3d/0xa2
...
when mprotect(2) gets used on DAX mappings. Also there is a wide variety
of other failures that can result from the missing _PAGE_DEVMAP flag
when the area gets used by get_user_pages() later.
Fix the problem by including _PAGE_DEVMAP in a set of flags that get
preserved by mprotect(2).
Fixes: 69660fd797c3 ("x86, mm: introduce _PAGE_DEVMAP")
Fixes: ebd31197931d ("powerpc/mm: Add devmap support for ppc64")
Cc: <stable@vger.kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Paolo writes:
"KVM fixes for 4.19-rc8
Leftover bugfixes."
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: vmx: hyper-v: don't pass EPT configuration info to vmx_hv_remote_flush_tlb()
KVM: x86: support CONFIG_KVM_AMD=y with CONFIG_CRYPTO_DEV_CCP_DD=m
ARM: KVM: Correctly order SGI register entries in the cp15 array
This function was renamed in commit 82fe39a6bc7b ("i2c: refactor
function to release a DMA safe buffer") but this kernel doc wasn't
updated to point at the new function. Rename it.
Fixes: 82fe39a6bc7b ("i2c: refactor function to release a DMA safe buffer")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
In the presence of multi-order entries the typical
pagevec_lookup_entries() pattern may loop forever:
while (index < end && pagevec_lookup_entries(&pvec, mapping, index,
min(end - index, (pgoff_t)PAGEVEC_SIZE),
indices)) {
...
for (i = 0; i < pagevec_count(&pvec); i++) {
index = indices[i];
...
}
index++; /* BUG */
}
The loop updates 'index' for each index found and then increments to the
next possible page to continue the lookup. However, if the last entry in
the pagevec is multi-order then the next possible page index is more
than 1 page away. Fix this locally for the filesystem-dax case by
checking for dax-multi-order entries. Going forward new users of
multi-order entries need to be similarly careful, or we need a generic
way to report the page increment in the radix iterator.
Fixes: 5fac7408d828 ("mm, fs, dax: handle layout changes to pinned dax...")
Cc: <stable@vger.kernel.org>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
ubifs_assert() is not WARN_ON(), so we have to invert
the checks.
Randy faced this warning with UBIFS being a module, since
most users use UBIFS as builtin because UBIFS is the rootfs
nobody noticed so far. :-(
Including me.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Fixes: 54169ddd382d ("ubifs: Turn two ubifs_assert() into a WARN_ON()")
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
I'm observing random crashes in multi-vCPU L2 guests running on KVM on
Hyper-V. I bisected the issue to the commit 877ad952be3d ("KVM: vmx: Add
tlb_remote_flush callback support"). Hyper-V TLFS states:
"AddressSpace specifies an address space ID (an EPT PML4 table pointer)"
So apparently, Hyper-V doesn't expect us to pass naked EPTP, only PML4
pointer should be used. Strip off EPT configuration information before
calling into vmx_hv_remote_flush_tlb().
Fixes: 877ad952be3d ("KVM: vmx: Add tlb_remote_flush callback support")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Fixes from Andrew:
* akpm:
fs/fat/fatent.c: add cond_resched() to fat_count_free_clusters()
mm/thp: fix call to mmu_notifier in set_pmd_migration_entry() v2
mm/mmap.c: don't clobber partially overlapping VMA with MAP_FIXED_NOREPLACE
ocfs2: fix a GCC warning
KVM/arm fixes for 4.19, take #2
- Correctly order GICv3 SGI registers in the cp15 array
I wrote:
"Char/Misc fixes for 4.19-rc7
Here are 8 small fixes for some char/misc driver issues
Included here are:
- fpga driver fixes
- thunderbolt bugfixes
- firmware core revert/fix
- hv core fix
- hv tool fix
All of these have been in linux-next with no reported issues."
* tag 'char-misc-4.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
thunderbolt: Initialize after IOMMUs
thunderbolt: Do not handle ICM events after domain is stopped
firmware: Always initialize the fw_priv list object
docs: fpga: document fpga manager flags
fpga: bridge: fix obvious function documentation error
tools: hv: fcopy: set 'error' in case an unknown operation was requested
fpga: do not access region struct after fpga_region_unregister
Drivers: hv: vmbus: Use get/put_cpu() in vmbus_connect()
Miguel writes:
"A trivial fix for auxdisplay
- MAINTAINERS reference fix for moved file
Reported by Joe Perches"
* tag 'auxdisplay-for-greg-v4.19-rc6' of https://github.com/ojeda/linux:
MAINTAINERS: fix reference to moved drivers/{misc => auxdisplay}/panel.c
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