Filipe Manana [Fri, 4 Sep 2020 16:22:57 +0000 (17:22 +0100)]
btrfs: fix NULL pointer dereference after failure to create snapshot
When trying to get a new fs root for a snapshot during the transaction
at transaction.c:create_pending_snapshot(), if btrfs_get_new_fs_root()
fails we leave "pending->snap" pointing to an error pointer, and then
later at ioctl.c:create_snapshot() we dereference that pointer, resulting
in a crash:
(gdb) list *(btrfs_mksubvol+0x438)
0x7c7b8 is in btrfs_mksubvol (fs/btrfs/ioctl.c:858).
853 ret = 0;
854 pending_snapshot->anon_dev = 0;
855 fail:
856 /* Prevent double freeing of anon_dev */
857 if (ret && pending_snapshot->snap)
858 pending_snapshot->snap->anon_dev = 0;
859 btrfs_put_root(pending_snapshot->snap);
860 btrfs_subvolume_release_metadata(root, &pending_snapshot->block_rsv);
861 free_pending:
862 if (pending_snapshot->anon_dev)
So fix this by setting "pending->snap" to NULL if we get an error from the
call to btrfs_get_new_fs_root() at transaction.c:create_pending_snapshot().
Fixes: 2dfb1e43f57dd3 ("btrfs: preallocate anon block device at first phase of snapshot creation") Signed-off-by: Filipe Manana <[email protected]> Reviewed-by: David Sterba <[email protected]> Signed-off-by: David Sterba <[email protected]>
usb: typec: intel_pmc_mux: Do not configure SBU and HSL Orientation in Alternate modes
According to the PMC Type C Subsystem (TCSS) Mux programming guide rev
0.7, bits 4 and 5 are reserved in Alternate modes.
SBU Orientation and HSL Orientation needs to be configured only during
initial cable detection in USB connect flow based on device property of
"sbu-orientation" and "hsl-orientation".
Configuring these reserved bits in the Alternate modes may result in delay
in display link training or some unexpected behaviour.
So do not configure them while issuing Alternate Mode requests.
usb: typec: intel_pmc_mux: Do not configure Altmode HPD High
According to the PMC Type C Subsystem (TCSS) Mux programming guide rev
0.7, bit 14 is reserved in Alternate mode.
In DP Alternate Mode state, if the HPD_STATE (bit 7) field in the
status update command VDO is set to HPD_HIGH, HPD is configured via
separate HPD mode request after configuring DP Alternate mode request.
Configuring reserved bit may show unexpected behaviour.
So do not configure them while issuing the Alternate Mode request.
Rustam Kovhaev [Mon, 10 Aug 2020 15:36:50 +0000 (08:36 -0700)]
scripts/tags.sh: exclude tools directory from tags generation
when COMPILED_SOURCE is set, running 'make ARCH=x86_64 COMPILED_SOURCE=1
cscope tags' in KBUILD_OUTPUT directory produces lots of "No such file
or directory" warnings:
...
realpath: sigchain.h: No such file or directory
realpath: orc_gen.c: No such file or directory
realpath: objtool.c: No such file or directory
...
let's exclude tools directory from tags generation
Josef Bacik [Thu, 3 Sep 2020 18:29:50 +0000 (14:29 -0400)]
btrfs: free data reloc tree on failed mount
While testing a weird problem with -o degraded, I noticed I was getting
leaked root errors
BTRFS warning (device loop0): writable mount is not allowed due to too many missing devices
BTRFS error (device loop0): open_ctree failed
BTRFS error (device loop0): leaked root -9-0 refcount 1
This is the DATA_RELOC root, which gets read before the other fs roots,
but is included in the fs roots radix tree. Handle this by adding a
btrfs_drop_and_free_fs_root() on the data reloc root if it exists. This
is ok to do here if we fail further up because we will only drop the ref
if we delete the root from the radix tree, and all other cleanup won't
be duplicated.
Qu Wenruo [Wed, 26 Aug 2020 09:26:43 +0000 (17:26 +0800)]
btrfs: require only sector size alignment for parent eb bytenr
[BUG]
A completely sane converted fs will cause kernel warning at balance
time:
[ 1557.188633] BTRFS info (device sda7): relocating block group 8162107392 flags data
[ 1563.358078] BTRFS info (device sda7): found 11722 extents
[ 1563.358277] BTRFS info (device sda7): leaf 7989321728 gen 95 total ptrs 213 free space 3458 owner 2
[ 1563.358280] item 0 key (7984947200 169 0) itemoff 16250 itemsize 33
[ 1563.358281] extent refs 1 gen 90 flags 2
[ 1563.358282] ref#0: tree block backref root 4
[ 1563.358285] item 1 key (7985602560 169 0) itemoff 16217 itemsize 33
[ 1563.358286] extent refs 1 gen 93 flags 258
[ 1563.358287] ref#0: shared block backref parent 7985602560
[ 1563.358288] (parent 7985602560 is NOT ALIGNED to nodesize 16384)
[ 1563.358290] item 2 key (7985635328 169 0) itemoff 16184 itemsize 33
...
[ 1563.358995] BTRFS error (device sda7): eb 7989321728 invalid extent inline ref type 182
[ 1563.358996] ------------[ cut here ]------------
[ 1563.359005] WARNING: CPU: 14 PID: 2930 at 0xffffffff9f231766
Then with transaction abort, and obviously failed to balance the fs.
[CAUSE]
That mentioned inline ref type 182 is completely sane, it's
BTRFS_SHARED_BLOCK_REF_KEY, it's some extra check making kernel to
believe it's invalid.
Commit 64ecdb647ddb ("Btrfs: add one more sanity check for shared ref
type") introduced extra checks for backref type.
One of the requirement is, parent bytenr must be aligned to node size,
which is not correct.
One example is like this:
0 1G 1G+4K 2G 2G+4K
| |///////////////////|//| <- A chunk starts at 1G+4K
| | <- A tree block get reserved at bytenr 1G+4K
Then we have a valid tree block at bytenr 1G+4K, but not aligned to
nodesize (16K).
Such chunk is not ideal, but current kernel can handle it pretty well.
We may warn about such tree block in the future, but should not reject
them.
[FIX]
Change the alignment requirement from node size alignment to sector size
alignment.
Also, to make our lives a little easier, also output @iref when
btrfs_get_extent_inline_ref_type() failed, so we can locate the item
easier.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=205475 Fixes: 64ecdb647ddb ("Btrfs: add one more sanity check for shared ref type") CC: [email protected] # 4.14+ Reviewed-by: Josef Bacik <[email protected]> Signed-off-by: Qu Wenruo <[email protected]>
[ update comments and messages ] Signed-off-by: David Sterba <[email protected]>
Josef Bacik [Mon, 31 Aug 2020 14:52:42 +0000 (10:52 -0400)]
btrfs: fix lockdep splat in add_missing_dev
Nikolay reported a lockdep splat in generic/476 that I could reproduce
with btrfs/187.
======================================================
WARNING: possible circular locking dependency detected
5.9.0-rc2+ #1 Tainted: G W
------------------------------------------------------
kswapd0/100 is trying to acquire lock: ffff9e8ef38b6268 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x3f/0x330
but task is already holding lock: ffffffffa9d74700 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
This is because we are holding the chunk_mutex when we call
btrfs_alloc_device, which does a GFP_KERNEL allocation. We don't want
to switch that to a GFP_NOFS lock because this is the only place where
it matters. So instead use memalloc_nofs_save() around the allocation
in order to avoid the lockdep splat.
openrisc: Fix cache API compile issue when not inlining
I found this when compiling a kbuild random config with GCC 11. The
config enables CONFIG_DEBUG_SECTION_MISMATCH, which sets CFLAGS
-fno-inline-functions-called-once. This causes the call to cache_loop in
cache.c to not be inlined causing the below compile error.
In file included from arch/openrisc/mm/cache.c:13:
arch/openrisc/mm/cache.c: In function 'cache_loop':
./arch/openrisc/include/asm/spr.h:16:27: warning: 'asm' operand 0 probably does not match constraints
16 | #define mtspr(_spr, _val) __asm__ __volatile__ ( \
| ^~~~~~~
arch/openrisc/mm/cache.c:25:3: note: in expansion of macro 'mtspr'
25 | mtspr(reg, line);
| ^~~~~
./arch/openrisc/include/asm/spr.h:16:27: error: impossible constraint in 'asm'
16 | #define mtspr(_spr, _val) __asm__ __volatile__ ( \
| ^~~~~~~
arch/openrisc/mm/cache.c:25:3: note: in expansion of macro 'mtspr'
25 | mtspr(reg, line);
| ^~~~~
make[1]: *** [scripts/Makefile.build:283: arch/openrisc/mm/cache.o] Error 1
The asm constraint "K" requires a immediate constant argument to mtspr,
however because of no inlining a register argument is passed causing a
failure. Fix this by using __always_inline.
Stafford Horne [Sun, 30 Aug 2020 11:58:11 +0000 (20:58 +0900)]
openrisc: Reserve memblock for initrd
Recently OpenRISC added support for external initrd images, but I found
some instability when using larger buildroot initrd images. It turned
out that I forgot to reserve the memblock space for the initrd image.
This patch fixes the instability issue by reserving memblock space.
Fixes: ff6c923dbec3 ("openrisc: Add support for external initrd images") Signed-off-by: Stafford Horne <[email protected]> Reviewed-by: Mike Rapoport <[email protected]>
Marek Vasut [Sat, 5 Sep 2020 15:19:13 +0000 (17:19 +0200)]
spi: stm32: Rate-limit the 'Communication suspended' message
The 'spi_stm32 44004000.spi: Communication suspended' message means that
when using PIO, the kernel did not read the FIFO fast enough and so the
SPI controller paused the transfer. Currently, this is printed on every
single such event, so if the kernel is busy and the controller is pausing
the transfers often, the kernel will be all the more busy scrolling this
message into the log buffer every few milliseconds. That is not helpful.
Instead, rate-limit the message and print it every once in a while. It is
not possible to use the default dev_warn_ratelimited(), because that is
still too verbose, as it prints 10 lines (DEFAULT_RATELIMIT_BURST) every
5 seconds (DEFAULT_RATELIMIT_INTERVAL). The policy here is to print 1 line
every 50 seconds (DEFAULT_RATELIMIT_INTERVAL * 10), because 1 line is more
than enough and the cycles saved on printing are better left to the CPU to
handle the SPI. However, dev_warn_once() is also not useful, as the user
should be aware that this condition is possibly recurring or ongoing. Thus
the custom rate-limit policy.
Finally, turn the message from dev_warn() to dev_dbg(), since the system
does not suffer any sort of malfunction if this message appears, it is
just slowing down. This further reduces the printing into the log buffer
and frees the CPU to do useful work.
This means that images can be mapped and unmapped (i.e. block devices
can be created and deleted) by a UID 0 process even after it drops all
privileges or by any process with CAP_DAC_OVERRIDE in its user namespace
as long as UID 0 is mapped into that user namespace.
Be consistent with other virtual block devices (loop, nbd, dm, md, etc)
and require CAP_SYS_ADMIN in the initial user namespace for mapping and
unmapping, and also for dumping the configuration string and refreshing
the image header.
Andy Shevchenko [Mon, 3 Aug 2020 08:35:20 +0000 (11:35 +0300)]
kobject: Drop unneeded conditional in __kobject_del()
__kobject_del() is called from two places, in one where kobj is dereferenced
before and thus can't be NULL, and in the other the NULL check is done before
call. Drop unneeded conditional in __kobject_del().
Adrian Hunter [Thu, 3 Sep 2020 08:20:07 +0000 (11:20 +0300)]
mmc: sdio: Use mmc_pre_req() / mmc_post_req()
SDHCI changed from using a tasklet to finish requests, to using an IRQ
thread i.e. commit c07a48c2651965 ("mmc: sdhci: Remove finish_tasklet").
Because this increased the latency to complete requests, a preparatory
change was made to complete the request from the IRQ handler if
possible i.e. commit 19d2f695f4e827 ("mmc: sdhci: Call mmc_request_done()
from IRQ handler if possible"). That alleviated the situation for MMC
block devices because the MMC block driver makes use of mmc_pre_req()
and mmc_post_req() so that successful requests are completed in the IRQ
handler and any DMA unmapping is handled separately in mmc_post_req().
However SDIO was still affected, and an example has been reported with
up to 20% degradation in performance.
Looking at SDIO I/O helper functions, sdio_io_rw_ext_helper() appeared
to be a possible candidate for making use of asynchronous requests
within its I/O loops, but analysis revealed that these loops almost
never iterate more than once, so the complexity of the change would not
be warrented.
Instead, mmc_pre_req() and mmc_post_req() are added before and after I/O
submission (mmc_wait_for_req) in mmc_io_rw_extended(). This still has
the potential benefit of reducing the duration of interrupt handlers, as
well as addressing the latency issue for SDHCI. It also seems a more
reasonable solution than forcing drivers to do everything in the IRQ
handler.
Chris Packham [Thu, 3 Sep 2020 01:20:29 +0000 (13:20 +1200)]
mmc: sdhci-of-esdhc: Don't walk device-tree on every interrupt
Commit b214fe592ab7 ("mmc: sdhci-of-esdhc: add erratum eSDHC7 support")
added code to check for a specific compatible string in the device-tree
on every esdhc interrupat. Instead of doing this record the quirk in
struct sdhci_esdhc and lookup the struct in esdhc_irq.
mmc: mmc_spi: Allow the driver to be built when CONFIG_HAS_DMA is unset
The commit cd57d07b1e4e ("sh: don't allow non-coherent DMA for NOMMU") made
CONFIG_NO_DMA to be set for some platforms, for good reasons.
Consequentially, CONFIG_HAS_DMA doesn't get set, which makes the DMA
mapping interface to be built as stub functions, but also prevent the
mmc_spi driver from being built as it depends on CONFIG_HAS_DMA.
It turns out that for some odd cases, the driver still relied on the DMA
mapping interface, even if the DMA was not actively being used.
To fixup the behaviour, let's drop the build dependency for CONFIG_HAS_DMA.
Moreover, as to allow the driver to succeed probing, let's move the DMA
initializations behind "#ifdef CONFIG_HAS_DMA".
Douglas Anderson [Thu, 27 Aug 2020 14:58:41 +0000 (07:58 -0700)]
mmc: sdhci-msm: Add retries when all tuning phases are found valid
As the comments in this patch say, if we tune and find all phases are
valid it's _almost_ as bad as no phases being found valid. Probably
all phases are not really reliable but we didn't detect where the
unreliable place is. That means we'll essentially be guessing and
hoping we get a good phase.
This is not just a problem in theory. It was causing real problems on
a real board. On that board, most often phase 10 is found as the only
invalid phase, though sometimes 10 and 11 are invalid and sometimes
just 11. Some percentage of the time, however, all phases are found
to be valid. When this happens, the current logic will decide to use
phase 11. Since phase 11 is sometimes found to be invalid, this is a
bad choice. Sure enough, when phase 11 is picked we often get mmc
errors later in boot.
I have seen cases where all phases were found to be valid 3 times in a
row, so increase the retry count to 10 just to be extra sure.
Raul E Rangel [Mon, 31 Aug 2020 21:10:32 +0000 (15:10 -0600)]
mmc: sdhci-acpi: Clear amd_sdhci_host on reset
The commit 61d7437ed1390 ("mmc: sdhci-acpi: Fix HS400 tuning for AMDI0040")
broke resume for eMMC HS400. When the system suspends the eMMC controller
is powered down. So, on resume we need to reinitialize the controller.
Although, amd_sdhci_host was not getting cleared, so the DLL was never
re-enabled on resume. This results in HS400 being non-functional.
To fix the problem, this change clears the tuned_clock flag, clears the
dll_enabled flag and disables the DLL on reset.
If during cifs_lookup()/get_inode_info() we encounter a DFS link
and we use the cifsacl or modefromsid mount options we must suppress
any -EREMOTE errors that triggers or else we will not be able to follow
the DFS link and automount the target.
This fixes an issue with modefromsid/cifsacl where these mountoptions
would break DFS and we would no longer be able to access the share.
Merge tag 'io_uring-5.9-2020-09-06' of git://git.kernel.dk/linux-block
Pull more io_uring fixes from Jens Axboe:
"Two followup fixes. One is fixing a regression from this merge window,
the other is two commits fixing cancelation of deferred requests.
Both have gone through full testing, and both spawned a few new
regression test additions to liburing.
- Don't play games with const, properly store the output iovec and
assign it as needed.
- Deferred request cancelation fix (Pavel)"
* tag 'io_uring-5.9-2020-09-06' of git://git.kernel.dk/linux-block:
io_uring: fix linked deferred ->files cancellation
io_uring: fix cancel of deferred reqs with ->files
io_uring: fix explicit async read/write mapping for large segments
Merge tag 'iommu-fixes-v5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull iommu fixes from Joerg Roedel:
- three Intel VT-d fixes to fix address handling on 32bit, fix a NULL
pointer dereference bug and serialize a hardware register access as
required by the VT-d spec.
- two patches for AMD IOMMU to force AMD GPUs into translation mode
when memory encryption is active and disallow using IOMMUv2
functionality. This makes the AMDGPU driver work when memory
encryption is active.
- two more fixes for AMD IOMMU to fix updating the Interrupt Remapping
Table Entries.
- MAINTAINERS file update for the Qualcom IOMMU driver.
* tag 'iommu-fixes-v5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/vt-d: Handle 36bit addressing for x86-32
iommu/amd: Do not use IOMMUv2 functionality when SME is active
iommu/amd: Do not force direct mapping when SME is active
iommu/amd: Use cmpxchg_double() when updating 128-bit IRTE
iommu/amd: Restore IRTE.RemapEn bit after programming IRTE
iommu/vt-d: Fix NULL pointer dereference in dev_iommu_priv_set()
iommu/vt-d: Serialize IOMMU GCMD register modifications
MAINTAINERS: Update QUALCOMM IOMMU after Arm SMMU drivers move
Merge tag 'x86-urgent-2020-09-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
- more generic entry code ABI fallout
- debug register handling bugfixes
- fix vmalloc mappings on 32-bit kernels
- kprobes instrumentation output fix on 32-bit kernels
- fix over-eager WARN_ON_ONCE() on !SMAP hardware
- NUMA debugging fix
- fix Clang related crash on !RETPOLINE kernels
* tag 'x86-urgent-2020-09-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/entry: Unbreak 32bit fast syscall
x86/debug: Allow a single level of #DB recursion
x86/entry: Fix AC assertion
tracing/kprobes, x86/ptrace: Fix regs argument order for i386
x86, fakenuma: Fix invalid starting node ID
x86/mm/32: Bring back vmalloc faulting on x86_32
x86/cmdline: Disable jump tables for cmdline.c
Merge tags 'auxdisplay-for-linus-v5.9-rc4', 'clang-format-for-linus-v5.9-rc4' and 'compiler-attributes-for-linus-v5.9-rc4' of git://github.com/ojeda/linux
Pull misc fixes from Miguel Ojeda:
"A trivial patch for auxdisplay:
- Replace HTTP links with HTTPS ones (Alexander A. Klimov)
The usual clang-format trivial update:
- Update with the latest for_each macro list (Miguel Ojeda)
And Luc requested me to pick a sparse fix on my queue, so here it goes
along with other two trivial Compiler Attributes ones (also from Luc).
- sparse: use static inline for __chk_{user,io}_ptr() (Luc Van
Oostenryck)
- Compiler Attributes: remove comment about sparse not supporting
__has_attribute (Luc Van Oostenryck)"
* tag 'auxdisplay-for-linus-v5.9-rc4' of git://github.com/ojeda/linux:
auxdisplay: Replace HTTP links with HTTPS ones
* tag 'clang-format-for-linus-v5.9-rc4' of git://github.com/ojeda/linux:
clang-format: Update with the latest for_each macro list
* tag 'compiler-attributes-for-linus-v5.9-rc4' of git://github.com/ojeda/linux:
sparse: use static inline for __chk_{user,io}_ptr()
Compiler Attributes: fix comment concerning GCC 4.6
Compiler Attributes: remove comment about sparse not supporting __has_attribute
Merge tag 'arc-5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC fixes from Vineet Gupta:
- HSDK-4xd Dev system: perf driver updates for sampling interrupt
- HSDK* Dev System: Ethernet broken [Evgeniy Didin]
- HIGHMEM broken (2 memory banks) [Mike Rapoport]
- show_regs() rewrite once and for all
- Other minor fixes
* tag 'arc-5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: [plat-hsdk]: Switch ethernet phy-mode to rgmii-id
arc: fix memory initialization for systems with two memory banks
irqchip/eznps: Fix build error for !ARC700 builds
ARC: show_regs: fix r12 printing and simplify
ARC: HSDK: wireup perf irq
ARC: perf: don't bail setup if pct irq missing in device-tree
ARC: pgalloc.h: delete a duplicated word + other fixes
Subsystems affected by this patch series: MAINTAINERS, ipc, fork,
checkpatch, lib, and mm (memcg, slub, pagemap, madvise, migration,
hugetlb)"
* emailed patches from Andrew Morton <[email protected]>:
include/linux/log2.h: add missing () around n in roundup_pow_of_two()
mm/khugepaged.c: fix khugepaged's request size in collapse_file
mm/hugetlb: fix a race between hugetlb sysctl handlers
mm/hugetlb: try preferred node first when alloc gigantic page from cma
mm/migrate: preserve soft dirty in remove_migration_pte()
mm/migrate: remove unnecessary is_zone_device_page() check
mm/rmap: fixup copying of soft dirty and uffd ptes
mm/migrate: fixup setting UFFD_WP flag
mm: madvise: fix vma user-after-free
checkpatch: fix the usage of capture group ( ... )
fork: adjust sysctl_max_threads definition to match prototype
ipc: adjust proc_ipc_sem_dointvec definition to match prototype
mm: track page table modifications in __apply_to_page_range()
MAINTAINERS: IA64: mark Status as Odd Fixes only
MAINTAINERS: add LLVM maintainers
MAINTAINERS: update Cavium/Marvell entries
mm: slub: fix conversion of freelist_corrupted()
mm: memcg: fix memcg reclaim soft lockup
memcg: fix use-after-free in uncharge_batch
David Howells [Fri, 4 Sep 2020 23:36:16 +0000 (16:36 -0700)]
mm/khugepaged.c: fix khugepaged's request size in collapse_file
collapse_file() in khugepaged passes PAGE_SIZE as the number of pages to
be read to page_cache_sync_readahead(). The intent was probably to read
a single page. Fix it to use the number of pages to the end of the
window instead.
Muchun Song [Fri, 4 Sep 2020 23:36:13 +0000 (16:36 -0700)]
mm/hugetlb: fix a race between hugetlb sysctl handlers
There is a race between the assignment of `table->data` and write value
to the pointer of `table->data` in the __do_proc_doulongvec_minmax() on
the other thread.
Fix this by duplicating the `table`, and only update the duplicate of
it. And introduce a helper of proc_hugetlb_doulongvec_minmax() to
simplify the code.
Li Xinhai [Fri, 4 Sep 2020 23:36:10 +0000 (16:36 -0700)]
mm/hugetlb: try preferred node first when alloc gigantic page from cma
Since commit cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic
hugepages using cma"), the gigantic page would be allocated from node
which is not the preferred node, although there are pages available from
that node. The reason is that the nid parameter has been ignored in
alloc_gigantic_page().
Besides, the __GFP_THISNODE also need be checked if user required to
alloc only from the preferred node.
After this patch, the preferred node is tried first before other allowed
nodes, and don't try to allocate from other nodes if __GFP_THISNODE is
specified. If user don't specify the preferred node, the current node
will be used as preferred node, which makes sure consistent behavior of
allocating gigantic and non-gigantic hugetlb page.
Ralph Campbell [Fri, 4 Sep 2020 23:36:07 +0000 (16:36 -0700)]
mm/migrate: preserve soft dirty in remove_migration_pte()
The code to remove a migration PTE and replace it with a device private
PTE was not copying the soft dirty bit from the migration entry. This
could lead to page contents not being marked dirty when faulting the page
back from device private memory.
Patch series "mm/migrate: preserve soft dirty in remove_migration_pte()".
I happened to notice this from code inspection after seeing Alistair
Popple's patch ("mm/rmap: Fixup copying of soft dirty and uffd ptes").
This patch (of 2):
The check for is_zone_device_page() and is_device_private_page() is
unnecessary since the latter is sufficient to determine if the page is a
device private page. Simplify the code for easier reading.
mm/rmap: fixup copying of soft dirty and uffd ptes
During memory migration a pte is temporarily replaced with a migration
swap pte. Some pte bits from the existing mapping such as the soft-dirty
and uffd write-protect bits are preserved by copying these to the
temporary migration swap pte.
However these bits are not stored at the same location for swap and
non-swap ptes. Therefore testing these bits requires using the
appropriate helper function for the given pte type.
Unfortunately several code locations were found where the wrong helper
function is being used to test soft_dirty and uffd_wp bits which leads to
them getting incorrectly set or cleared during page-migration.
Fix these by using the correct tests based on pte type.
Commit f45ec5ff16a75 ("userfaultfd: wp: support swap and page migration")
introduced support for tracking the uffd wp bit during page migration.
However the non-swap PTE variant was used to set the flag for zone device
private pages which are a type of swap page.
This leads to corruption of the swap offset if the original PTE has the
uffd_wp flag set.
Yang Shi [Fri, 4 Sep 2020 23:35:55 +0000 (16:35 -0700)]
mm: madvise: fix vma user-after-free
The syzbot reported the below use-after-free:
BUG: KASAN: use-after-free in madvise_willneed mm/madvise.c:293 [inline]
BUG: KASAN: use-after-free in madvise_vma mm/madvise.c:942 [inline]
BUG: KASAN: use-after-free in do_madvise.part.0+0x1c8b/0x1cf0 mm/madvise.c:1145
Read of size 8 at addr ffff8880a6163eb0 by task syz-executor.0/9996
checkpatch: fix the usage of capture group ( ... )
The usage of "capture group (...)" in the immediate condition after `&&`
results in `$1` being uninitialized. This issues a warning "Use of
uninitialized value $1 in regexp compilation at ./scripts/checkpatch.pl
line 2638".
I noticed this bug while running checkpatch on the set of commits from
v5.7 to v5.8-rc1 of the kernel on the commits with a diff content in
their commit message.
This bug was introduced in the script by commit e518e9a59ec3
("checkpatch: emit an error when there's a diff in a changelog"). It
has been in the script since then.
The author intended to store the match made by capture group in variable
`$1`. This should have contained the name of the file as `[\w/]+`
matched. However, this couldn't be accomplished due to usage of capture
group and `$1` in the same regular expression.
Fix this by placing the capture group in the condition before `&&`.
Thus, `$1` can be initialized to the text that capture group matches
thereby setting it to the desired and required value.
fork: adjust sysctl_max_threads definition to match prototype
Commit 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler")
changed ctl_table.proc_handler to take a kernel pointer. Adjust the
definition of sysctl_max_threads to match its prototype in
linux/sysctl.h which fixes the following sparse error/warning:
kernel/fork.c:3050:47: warning: incorrect type in argument 3 (different address spaces)
kernel/fork.c:3050:47: expected void *
kernel/fork.c:3050:47: got void [noderef] __user *buffer
kernel/fork.c:3036:5: error: symbol 'sysctl_max_threads' redeclared with different type (incompatible argument 3 (different address spaces)):
kernel/fork.c:3036:5: int extern [addressable] [signed] [toplevel] sysctl_max_threads( ... )
kernel/fork.c: note: in included file (through include/linux/key.h, include/linux/cred.h, include/linux/sched/signal.h, include/linux/sched/cputime.h):
include/linux/sysctl.h:242:5: note: previously declared as:
include/linux/sysctl.h:242:5: int extern [addressable] [signed] [toplevel] sysctl_max_threads( ... )
ipc: adjust proc_ipc_sem_dointvec definition to match prototype
Commit 32927393dc1c ("sysctl: pass kernel pointers to ->proc_handler")
changed ctl_table.proc_handler to take a kernel pointer. Adjust the
signature of proc_ipc_sem_dointvec to match ctl_table.proc_handler which
fixes the following sparse error/warning:
ipc/ipc_sysctl.c:94:47: warning: incorrect type in argument 3 (different address spaces)
ipc/ipc_sysctl.c:94:47: expected void *buffer
ipc/ipc_sysctl.c:94:47: got void [noderef] __user *buffer
ipc/ipc_sysctl.c:194:35: warning: incorrect type in initializer (incompatible argument 3 (different address spaces))
ipc/ipc_sysctl.c:194:35: expected int ( [usertype] *proc_handler )( ... )
ipc/ipc_sysctl.c:194:35: got int ( * )( ... )
mm: track page table modifications in __apply_to_page_range()
__apply_to_page_range() is also used to change and/or allocate
page-table pages in the vmalloc area of the address space. Make sure
these changes get synchronized to other page-tables in the system by
calling arch_sync_kernel_mappings() when necessary.
The impact appears limited to x86-32, where apply_to_page_range may miss
updating the PMD. That leads to explosions in drivers like
Nominate Nathan and myself to be point of contact for clang/LLVM related
support, after a poll at the LLVM BoF at Linux Plumbers Conf 2020.
While corporate sponsorship is beneficial, its important to not entrust
the keys to the nukes with any one entity. Should Nathan and I find
ourselves at the same employer, I would gladly step down.
Robert Richter [Fri, 4 Sep 2020 23:35:33 +0000 (16:35 -0700)]
MAINTAINERS: update Cavium/Marvell entries
I am leaving Marvell and already do not have access to my @marvell.com
email address. So switching over to my korg mail address or removing my
address there another maintainer is already listed. For the entries
there no other maintainer is listed I will keep looking into patches for
Cavium systems for a while until someone from Marvell takes it over.
Since I might have limited access to hardware and also limited time I
changed state to 'Odd Fixes' for those entries.
Commit 52f23478081ae0 ("mm/slub.c: fix corrupted freechain in
deactivate_slab()") suffered an update when picked up from LKML [1].
Specifically, relocating 'freelist = NULL' into 'freelist_corrupted()'
created a no-op statement. Fix it by sticking to the behavior intended
in the original patch [1]. In addition, make freelist_corrupted()
immune to passing NULL instead of &freelist.
The issue has been spotted via static analysis and code review.
It only happens on our 1-vcpu instances, because there's no chance for
oom reaper to run to reclaim the to-be-killed process.
Add a cond_resched() at the upper shrink_node_memcgs() to solve this
issue, this will mean that we will get a scheduling point for each memcg
in the reclaimed hierarchy without any dependency on the reclaimable
memory in that memcg thus making it more predictable.
Commit 1a3e1f40962c ("mm: memcontrol: decouple reference counting from
page accounting") reworked the memcg lifetime to be bound the the struct
page rather than charges. It also removed the css_put_many from
uncharge_batch and that is causing the above splat.
uncharge_batch() is supposed to uncharge accumulated charges for all
pages freed from the same memcg. The queuing is done by uncharge_page
which however drops the memcg reference after it adds charges to the
batch. If the current page happens to be the last one holding the
reference for its memcg then the memcg is OK to go and the next page to
be freed will trigger batched uncharge which needs to access the memcg
which is gone already.
Fix the issue by taking a reference for the memcg in the current batch.
Merge tag 'xfs-5.9-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fix from Darrick Wong:
"Fix a broken metadata verifier that would incorrectly validate attr
fork extents of a realtime file against the realtime volume"
* tag 'xfs-5.9-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: fix xfs_bmap_validate_extent_raw when checking attr fork of rt files
When running in a dax mode, if the user maps a page with MAP_PRIVATE and
PROT_WRITE, the xfs filesystem would incorrectly update ctime and mtime
when the user hits a COW fault.
This breaks building of the Linux kernel. How to reproduce:
1. extract the Linux kernel tree on dax-mounted xfs filesystem
2. run make clean
3. run make -j12
4. run make -j12
at step 4, make would incorrectly rebuild the whole kernel (although it
was already built in step 3).
The reason for the breakage is that almost all object files depend on
objtool. When we run objtool, it takes COW page fault on its .data
section, and these faults will incorrectly update the timestamp of the
objtool binary. The updated timestamp causes make to rebuild the whole
tree.
When running in a dax mode, if the user maps a page with MAP_PRIVATE and
PROT_WRITE, the ext2 filesystem would incorrectly update ctime and mtime
when the user hits a COW fault.
This breaks building of the Linux kernel. How to reproduce:
1. extract the Linux kernel tree on dax-mounted ext2 filesystem
2. run make clean
3. run make -j12
4. run make -j12
at step 4, make would incorrectly rebuild the whole kernel (although it
was already built in step 3).
The reason for the breakage is that almost all object files depend on
objtool. When we run objtool, it takes COW page fault on its .data
section, and these faults will incorrectly update the timestamp of the
objtool binary. The updated timestamp causes make to rebuild the whole
tree.
The dpsub driver uses the DMA engine API, and thus selects DMA_ENGINE to
provide that API. DMA_ENGINE depends on DMADEVICES, which can be
deselected by the user, creating a possibly unmet indirect dependency:
WARNING: unmet direct dependencies detected for DMA_ENGINE
Depends on [n]: DMADEVICES [=n]
Selected by [m]:
- DRM_ZYNQMP_DPSUB [=m] && HAS_IOMEM [=y] && (ARCH_ZYNQMP || COMPILE_TEST [=y]) && COMMON_CLK [=y] && DRM [=m] && OF [=y]
Enabling a whole subsystem from a single driver 'select' is frowned
upon and won't be accepted in new drivers, that need to use 'depends on'
instead. Existing selection of DMAENGINES will then cause circular
dependencies. Replace them with a dependency.
io_uring: fix explicit async read/write mapping for large segments
If we exceed UIO_FASTIOV, we don't handle the transition correctly
between an allocated vec for requests that are queued with IOSQE_ASYNC.
Store the iovec appropriately and re-set it in the iter iov in case
it changed.
Fixes: ff6165b2d7f6 ("io_uring: retain iov_iter state over io_read/io_write calls") Reported-by: Nick Hill <[email protected]> Tested-by: Norman Maurer <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
J. Bruce Fields [Sat, 5 Sep 2020 14:03:26 +0000 (10:03 -0400)]
SUNRPC: stop printk reading past end of string
Since p points at raw xdr data, there's no guarantee that it's NULL
terminated, so we should give a length. And probably escape any special
characters too.
Chuck Lever [Fri, 4 Sep 2020 21:39:12 +0000 (17:39 -0400)]
NFS: Zero-stateid SETATTR should first return delegation
If a write delegation isn't available, the Linux NFS client uses
a zero-stateid when performing a SETATTR.
NFSv4.0 provides no mechanism for an NFS server to match such a
request to a particular client. It recalls all delegations for that
file, even delegations held by the client issuing the request. If
that client happens to hold a read delegation, the server will
recall it immediately, resulting in an NFS4ERR_DELAY/CB_RECALL/
DELEGRETURN sequence.
Optimize out this pipeline bubble by having the client return any
delegations it may hold on a file before it issues a
SETATTR(zero-stateid) on that file.
Merge tag 's390-5.9-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Vasily Gorbik:
- Fix GENERIC_LOCKBREAK dependency on PREEMPTION in Kconfig broken
because of a typo
- Update defconfigs
* tag 's390-5.9-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390: update defconfigs
s390: fix GENERIC_LOCKBREAK dependency typo in Kconfig
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Catalin Marinas:
- Fix the loading of modules built with binutils-2.35. This version
produces writable and executable .text.ftrace_trampoline section
which is rejected by the kernel.
- Remove the exporting of cpu_logical_map() as the Tegra driver has now
been fixed and no longer uses this function.
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64/module: set trampoline section flags regardless of CONFIG_DYNAMIC_FTRACE
arm64: Remove exporting cpu_logical_map symbol
Merge tag 'kbuild-fixes-v5.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
- fix documents
- fix warning in 'make localmodconfig'
* tag 'kbuild-fixes-v5.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: remove redundant assignment prompt = prompt
kbuild: Documentation: clean up makefiles.rst
kconfig: streamline_config.pl: check defined(ENV variable) before using it
Documentation/llvm: Improve formatting of commands, variables, and arguments
Merge tag 'pm-5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"These fix reference counting in the operating performance points (OPP)
framework and address a few intel_pstate driver issues, mostly related
to switching driver operation modes and similar with hardware-managed
P-states (HWP) enabled.
- Address intel_pstate driver interface issues, mostly related to
switching operation modes and handling CPU offline and online and
system-wide suspend/resume with hardware-managed P-states (HWP)
enabled (Rafael Wysocki).
- Fix the maximum frequency computation in the intel_pstate driver
with turbo P-states disabled by the platform firmware and HWP
enabled (Francisco Jerez)"
* tag 'pm-5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: intel_pstate: Fix intel_pstate_get_hwp_max() for turbo disabled
cpufreq: intel_pstate: Free memory only when turning off
cpufreq: intel_pstate: Add ->offline and ->online callbacks
cpufreq: intel_pstate: Tweak the EPP sysfs interface
cpufreq: intel_pstate: Update cached EPP in the active mode
cpufreq: intel_pstate: Refuse to turn off with HWP enabled
opp: Don't drop reference for an OPP table that was never parsed
Merge tag 'libata-5.9-2020-09-04' of git://git.kernel.dk/linux-block
Pull libata fixes from Jens Axboe:
- improve Sandisks ATA_HORKAGE on NCQ (Tejun)
- link printk cleanup (Xu)
* tag 'libata-5.9-2020-09-04' of git://git.kernel.dk/linux-block:
libata: implement ATA_HORKAGE_MAX_TRIM_128M and apply to Sandisks
ata: ahci: use ata_link_info() instead of ata_link_printk()
Merge tag 'block-5.9-2020-09-04' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"A bit larger than usual this week, mostly due to the NVMe fixes
arriving late for -rc3 and hence didn't make last weeks pull request.
- NVMe:
- instance leak and io boundary fixes from Keith
- fc locking fix from Christophe
- various tcp/rdma reset during traffic fixes from Sagi
- pci use-after-free fix from Tong
- tcp target null deref fix from Ziye
- Locking fix for partition removal (Christoph)
- Ensure bdi->io_pages is always set (me)
- Fixup for hd struct reference (Ming)
- Fix for zero length bvecs (Ming)
- Two small blk-iocost fixes (Tejun)"
* tag 'block-5.9-2020-09-04' of git://git.kernel.dk/linux-block:
block: allow for_each_bvec to support zero len bvec
blk-stat: make q->stats->lock irqsafe
blk-iocost: ioc_pd_free() shouldn't assume irq disabled
block: fix locking in bdev_del_partition
block: release disk reference in hd_struct_free_work
block: ensure bdi->io_pages is always initialized
nvme-pci: cancel nvme device request before disabling
nvme: only use power of two io boundaries
nvme: fix controller instance leak
nvmet-fc: Fix a missed _irqsave version of spin_lock in 'nvmet_fc_fod_op_done()'
nvme: Fix NULL dereference for pci nvme controllers
nvme-rdma: fix reset hang if controller died in the middle of a reset
nvme-rdma: fix timeout handler
nvme-rdma: serialize controller teardown sequences
nvme-tcp: fix reset hang if controller died in the middle of a reset
nvme-tcp: fix timeout handler
nvme-tcp: serialize controller teardown sequences
nvme: have nvme_wait_freeze_timeout return if it timed out
nvme-fabrics: don't check state NVME_CTRL_NEW for request acceptance
nvmet-tcp: Fix NULL dereference when a connect data comes in h2cdata pdu
Merge tag 'io_uring-5.9-2020-09-04' of git://git.kernel.dk/linux-block
Pull io_uring fixes from Jens Axboe:
- EAGAIN with O_NONBLOCK retry fix
- Two small fixes for registered files (Jiufei)
* tag 'io_uring-5.9-2020-09-04' of git://git.kernel.dk/linux-block:
io_uring: no read/write-retry on -EAGAIN error and O_NONBLOCK marked file
io_uring: set table->files[i] to NULL when io_sqe_file_register failed
io_uring: fix removing the wrong file in __io_sqe_files_update()
Merge tag 'thermal-v5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux
Pull thermal fixes from Daniel Lezcano:
- Fix bogus thermal shutdowns for omap4430 where bogus values resulting
from an incorrect ADC conversion are too high and fire an emergency
shutdown (Tony Lindgren)
- Don't suppress negative temp for qcom spmi as they are valid and
userspace needs them (Veera Vegivada)
- Fix use-after-free in thermal_zone_device_unregister reported by
Kasan (Dmitry Osipenko)
* tag 'thermal-v5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux:
thermal: core: Fix use-after-free in thermal_zone_device_unregister()
thermal: qcom-spmi-temp-alarm: Don't suppress negative temp
thermal: ti-soc-thermal: Fix bogus thermal shutdowns for omap4430
Jordan Crouse [Fri, 4 Sep 2020 02:03:11 +0000 (20:03 -0600)]
drm/msm: Enable expanded apriv support for a650
a650 supports expanded apriv support that allows us to map critical buffers
(ringbuffer and memstore) as as privileged to protect them from corruption.
Jordan Crouse [Fri, 4 Sep 2020 02:03:10 +0000 (20:03 -0600)]
drm/msm: Split the a5xx preemption record
The main a5xx preemption record can be marked as privileged to
protect it from user access but the counters storage needs to be
remain unprivileged. Split the buffers and mark the critical memory
as privileged.
Merge tag 'dmaengine-fix-5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine
Pull dmaengine fixes from Vinod Koul:
"A couple of core fixes and odd driver fixes for dmaengine subsystem:
Core:
- drop ACPI CSRT table reference after using it
- fix of_dma_router_xlate() error handling
Drivers fixes in idxd, at_hdmac, pl330, dw-edma and jz478"
* tag 'dmaengine-fix-5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine:
dmaengine: ti: k3-udma: Update rchan_oes_offset for am654 SYSFW ABI 3.0
drivers/dma/dma-jz4780: Fix race condition between probe and irq handler
dmaengine: dw-edma: Fix scatter-gather address calculation
dmaengine: ti: k3-udma: Fix the TR initialization for prep_slave_sg
dmaengine: pl330: Fix burst length if burst size is smaller than bus width
dmaengine: at_hdmac: add missing kfree() call in at_dma_xlate()
dmaengine: at_hdmac: add missing put_device() call in at_dma_xlate()
dmaengine: at_hdmac: check return value of of_find_device_by_node() in at_dma_xlate()
dmaengine: of-dma: Fix of_dma_router_xlate's of_dma_xlate handling
dmaengine: idxd: reset states after device disable or reset
dmaengine: acpi: Put the CSRT table after using it
Merge tag 'sound-5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"A collection of small changes, nothing intrusive:
- remaining tasklet API conversions, now all sound stuff have been
converted
- a few HD-audio and USB-audio quirks and minor fixes
- FireWire Tascam and Digi00xx fixes
- drop a kernel WARNING from PCM OSS for syzkaller"
* tag 'sound-5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (29 commits)
ALSA: hda/realtek - Improved routing for Thinkpad X1 7th/8th Gen
ALSA: hda: use consistent HDAudio spelling in comments/docs
ALSA: hda: add dev_dbg log when driver is not selected
ALSA: hda: fix a runtime pm issue in SOF when integrated GPU is disabled
ALSA: hda: hdmi - add Rocketlake support
ALSA: ua101: convert tasklets to use new tasklet_setup() API
ALSA: usb-audio: convert tasklets to use new tasklet_setup() API
ASoC: txx9: convert tasklets to use new tasklet_setup() API
ASoC: siu: convert tasklets to use new tasklet_setup() API
ASoC: fsl_esai: convert tasklets to use new tasklet_setup() API
ALSA: hdsp: convert tasklets to use new tasklet_setup() API
ALSA: riptide: convert tasklets to use new tasklet_setup() API
ALSA: pci/asihpi: convert tasklets to use new tasklet_setup() API
ALSA: firewire: convert tasklets to use new tasklet_setup() API
ALSA: core: convert tasklets to use new tasklet_setup() API
ALSA: pcm: oss: Remove superfluous WARN_ON() for mulaw sanity check
ALSA: hda - Fix silent audio output and corrupted input on MSI X570-A PRO
ALSA: hda/hdmi: always check pin power status in i915 pin fixup
ALSA: hda/realtek: Add quirk for Samsung Galaxy Book Ion NT950XCJ-X716A
ALSA: usb-audio: Add basic capture support for Pioneer DJ DJM-250MK2
...
Merge tag 'drm-fixes-2020-09-04' of git://anongit.freedesktop.org/drm/drm
Pull drm fixes from Dave Airlie:
"Not much going on this week, nouveau has a display hw bug workaround,
amdgpu has some PM fixes and CIK regression fixes, one single radeon
PLL fix, and a couple of i915 display fixes.
amdgpu:
- Fix for 32bit systems
- SW CTF fix
- Update for Sienna Cichlid
- CIK bug fixes
radeon:
- PLL fix
i915:
- Clang build warning fix
- HDCP fixes
nouveau:
- display fixes"
* tag 'drm-fixes-2020-09-04' of git://anongit.freedesktop.org/drm/drm:
drm/nouveau/kms/nv50-gp1xx: add WAR for EVO push buffer HW bug
drm/nouveau/kms/nv50-gp1xx: disable notifies again after core update
drm/nouveau/kms/nv50-: add some whitespace before debug message
drm/nouveau/kms/gv100-: Include correct push header in crcc37d.c
drm/radeon: Prefer lower feedback dividers
drm/amdgpu: Fix bug in reporting voltage for CIK
drm/amdgpu: Specify get_argument function for ci_smu_funcs
drm/amd/pm: enable MP0 DPM for sienna_cichlid
drm/amd/pm: avoid false alarm due to confusing softwareshutdowntemp setting
drm/amd/pm: fix is_dpm_running() run error on 32bit system
drm/i915: Clear the repeater bit on HDCP disable
drm/i915: Fix sha_text population code
drm/i915/display: Ensure that ret is always initialized in icl_combo_phy_verify_state
Or Cohen [Fri, 4 Sep 2020 04:05:28 +0000 (21:05 -0700)]
net/packet: fix overflow in tpacket_rcv
Using tp_reserve to calculate netoff can overflow as
tp_reserve is unsigned int and netoff is unsigned short.
This may lead to macoff receving a smaller value then
sizeof(struct virtio_net_hdr), and if po->has_vnet_hdr
is set, an out-of-bounds write will occur when
calling virtio_net_hdr_from_skb.
The bug is fixed by converting netoff to unsigned int
and checking if it exceeds USHRT_MAX.
Merge emailed patches from Peter Xu:
"This is a small series that I picked up from Linus's suggestion to
simplify cow handling (and also make it more strict) by checking
against page refcounts rather than mapcounts.
This makes uffd-wp work again (verified by running upmapsort)"
Note: this is horrendously bad timing, and making this kind of
fundamental vm change after -rc3 is not at all how things should work.
The saving grace is that it really is a a nice simplification:
The reason for the bad timing is that it turns out that commit 17839856fd58 ("gup: document and work around 'COW can break either way'
issue" broke not just UFFD functionality (as Peter noticed), but Mikulas
Patocka also reports that it caused issues for strace when running in a
DAX environment with ext4 on a persistent memory setup.
And we can't just revert that commit without re-introducing the original
issue that is a potential security hole, so making COW stricter (and in
the process much simpler) is a step to then undoing the forced COW that
broke other uses.
* pm-cpufreq:
cpufreq: intel_pstate: Fix intel_pstate_get_hwp_max() for turbo disabled
cpufreq: intel_pstate: Free memory only when turning off
cpufreq: intel_pstate: Add ->offline and ->online callbacks
cpufreq: intel_pstate: Tweak the EPP sysfs interface
cpufreq: intel_pstate: Update cached EPP in the active mode
cpufreq: intel_pstate: Refuse to turn off with HWP enabled
Peter Xu [Fri, 21 Aug 2020 23:49:57 +0000 (19:49 -0400)]
mm/gup: Remove enfornced COW mechanism
With the more strict (but greatly simplified) page reuse logic in
do_wp_page(), we can safely go back to the world where cow is not
enforced with writes.
This essentially reverts commit 17839856fd58 ("gup: document and work
around 'COW can break either way' issue"). There are some context
differences due to some changes later on around it:
driver core: Fix device_pm_lock() locking for device links
This commit fixes two issues:
1. The lockdep warning reported by Dong Aisheng <[email protected]> [1].
It is a warning about a cycle (dpm_list_mtx --> kn->active#3 --> fw_lock)
that was introduced when device-link devices were added to expose device
link information in sysfs.
The patch that "introduced" this cycle can't be reverted because it's fixes
a real SRCU issue and also ensures that the device-link device is deleted
as soon as the device-link is deleted. This is important to avoid sysfs
name collisions if the device-link is create again immediately (this can
happen a lot with deferred probing).
2. Inconsistency in grabbing device_pm_lock() during device link deletion
Some device link deletion code paths grab device_pm_lock(), while others
don't. The device_pm_lock() is grabbed during device_link_add() because it
checks if the supplier is in the dpm_list and also reorders the dpm_list.
However, when a device link is deleted, it does not do either of those and
therefore device_pm_lock() is not necessary. Dropping the device_pm_lock()
in all the device link deletion paths removes the inconsistency in locking.
Thanks to Stephen Boyd for helping me understand the lockdep splat.
Vladis Dronov [Tue, 11 Aug 2020 15:01:29 +0000 (17:01 +0200)]
debugfs: Fix module state check condition
The '#ifdef MODULE' check in the original commit does not work as intended.
The code under the check is not built at all if CONFIG_DEBUG_FS=y. Fix this
by using a correct check.
Jim Cromie [Mon, 31 Aug 2020 18:22:10 +0000 (12:22 -0600)]
dyndbg: fix problem parsing format="foo bar"
commit 14775b049642 ("dyndbg: accept query terms like file=bar and
module=foo") added the combined keyword=value parsing poorly; revert
most of it, keeping the keyword & arg change.
Instead, fix the tokenizer for the new input, by terminating the
keyword (an unquoted word) on '=' as well as space, thus letting the
tokenizer work on the quoted argument, like it would have previously.
Also add a few debug-prints to show more parsing context, into
tokenizer and parse-query, and use "keyword, value" in others.
Jim Cromie [Mon, 31 Aug 2020 18:22:09 +0000 (12:22 -0600)]
dyndbg: refine export, rename to dynamic_debug_exec_queries()
commit 4c0d77828d4f ("dyndbg: export ddebug_exec_queries") had a few
problems:
- broken non DYNAMIC_DEBUG_CORE configs, sparse warning
- the exported function modifies query string, breaks on RO strings.
- func name follows internal convention, shouldn't be exposed as is.
1st is fixed in header with ifdefd function prototype or stub defn.
Also remove an obsolete HAVE-symbol ifdef-comment, and add others.
Fix others by wrapping existing internal function with a new one,
named in accordance with module-prefix naming convention, before
export hits v5.9.0. In new function, copy query string to a local
buffer, so users can pass hard-coded/RO queries, and internal function
can be used unchanged.
Zeng Tao [Fri, 4 Sep 2020 06:37:44 +0000 (14:37 +0800)]
usb: core: fix slab-out-of-bounds Read in read_descriptors
The USB device descriptor may get changed between two consecutive
enumerations on the same device for some reason, such as DFU or
malicius device.
In that case, we may access the changing descriptor if we don't take
the device lock here.
This commit breaks USB on meson-gxl-s905x-libretech-cc. Reverting
the change solves the issue.
In fact, according to the reset framework code, consumers must not use
reset_control_(de)assert() on shared reset lines when reset_control_reset
has been used, and vice-versa.
Moreover, with this commit, usb is not guaranted to be reset since the
reset is likely to be initially deasserted.
Reverting the commit will bring back the suspend warning mentioned in the
commit description. Nevertheless, a warning is much less critical than
breaking dwc3-meson-g12a USB completely. We will address the warning
issue in another way as a 2nd step.
Heikki Krogerus [Fri, 4 Sep 2020 11:09:18 +0000 (14:09 +0300)]
usb: typec: ucsi: acpi: Check the _DEP dependencies
Failing probe with -EPROBE_DEFER until all dependencies
listed in the _DEP (Operation Region Dependencies) object
have been met.
This will fix an issue where on some platforms UCSI ACPI
driver fails to probe because the address space handler for
the operation region that the UCSI ACPI interface uses has
not been loaded yet.
usb: Fix out of sync data toggle if a configured device is reconfigured
Userspace drivers that use a SetConfiguration() request to "lightweight"
reset an already configured usb device might cause data toggles to get out
of sync between the device and host, and the device becomes unusable.
The xHCI host requires endpoints to be dropped and added back to reset the
toggle. If USB core notices the new configuration is the same as the
current active configuration it will avoid these extra steps by calling
usb_reset_configuration() instead of usb_set_configuration().
A SetConfiguration() request will reset the device side data toggles.
Make sure usb_reset_configuration() function also drops and adds back the
endpoints to ensure data toggles are in sync.
To avoid code duplication split the current usb_disable_device() function
and reuse the endpoint specific part.
The eason is that the conversion to generic entry code moved the retrieval
of the sixth argument (EBP) after the point where the syscall entry work
runs, i.e. ptrace, seccomp, audit...
Unbreak it by providing a split up version of syscall_enter_from_user_mode().
- syscall_enter_from_user_mode_prepare() establishes state and enables
interrupts
- syscall_enter_from_user_mode_work() runs the entry work
Replace the call to syscall_enter_from_user_mode() in the 32bit fast
syscall C-entry with the split functions and stick the EBP retrieval
between them.
Andy Lutomirski [Wed, 2 Sep 2020 13:25:51 +0000 (15:25 +0200)]
x86/debug: Allow a single level of #DB recursion
Trying to clear DR7 around a #DB from usermode malfunctions if the tasks
schedules when delivering SIGTRAP.
Rather than trying to define a special no-recursion region, just allow a
single level of recursion. The same mechanism is used for NMI, and it
hasn't caused any problems yet.
Peter Zijlstra [Wed, 2 Sep 2020 13:25:50 +0000 (15:25 +0200)]
x86/entry: Fix AC assertion
The WARN added in commit 3c73b81a9164 ("x86/entry, selftests: Further
improve user entry sanity checks") unconditionally triggers on a IVB
machine because it does not support SMAP.
For !SMAP hardware the CLAC/STAC instructions are patched out and thus if
userspace sets AC, it is still have set after entry.
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