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When increase_address_space() fails to allocate memory, alloc_pte()
will call it again until it succeeds. Do not loop forever while trying
to increase the address space and just return an error instead.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Tested-by: Qian Cai <cai@lca.pw>
Link: https://lore.kernel.org/r/20200504125413.16798-3-joro@8bytes.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The 'pt_root' and 'mode' struct members of 'struct protection_domain'
need to be get/set atomically, otherwise the page-table of the domain
can get corrupted.
Merge the fields into one atomic64_t struct member which can be
get/set atomically.
Fixes: 92d420ec028d ("iommu/amd: Relax locking in dma_ops path")
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Tested-by: Qian Cai <cai@lca.pw>
Link: https://lore.kernel.org/r/20200504125413.16798-2-joro@8bytes.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Pull more btrfs fixes from David Sterba:
"A few more stability fixes, minor build warning fixes and git url
fixup:
- fix partial loss of prealloc extent past i_size after fsync
- fix potential deadlock due to wrong transaction handle passing via
journal_info
- fix gcc 4.8 struct intialization warning
- update git URL in MAINTAINERS entry"
* tag 'for-5.7-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
MAINTAINERS: btrfs: fix git repo URL
btrfs: fix gcc-4.8 build warning for struct initializer
btrfs: transaction: Avoid deadlock due to bad initialization timing of fs_info::journal_info
btrfs: fix partial loss of prealloc extent past i_size after fsync
Pull IOMMU fixes from Joerg Roedel:
- Fix a memory leak when dev_iommu gets freed and a sub-pointer does
not
- Build dependency fixes for Mediatek, spapr_tce, and Intel IOMMU
driver
- Export iommu_group_get_for_dev() only for GPLed modules
- Fix AMD IOMMU interrupt remapping when x2apic is enabled
- Fix error path in the QCOM IOMMU driver probe function
* tag 'iommu-fixes-v5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/qcom: Fix local_base status check
iommu: Properly export iommu_group_get_for_dev()
iommu/vt-d: Use right Kconfig option name
iommu/amd: Fix legacy interrupt remapping for x2APIC-enabled system
iommu: spapr_tce: Disable compile testing to fix build on book3s_32 config
iommu/mediatek: Fix MTK_IOMMU dependencies
iommu: Fix the memory leak in dev_iommu_free()
The git repo listed for btrfs hasn't been updated in over a year.
List the current one instead.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull power management fixes from Rafael Wysocki:
- prevent the intel_pstate driver from printing excessive diagnostic
messages in some cases (Chris Wilson)
- make the hibernation restore kernel freeze kernel threads as well as
user space tasks (Dexuan Cui)
- fix the ACPI device PM disagnostic messages to include the correct
power state name (Kai-Heng Feng).
* tag 'pm-5.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM: ACPI: Output correct message on target power state
PM: hibernate: Freeze kernel threads in software_resume()
cpufreq: intel_pstate: Only mention the BIOS disabling turbo mode once
The function qcom_iommu_device_probe() does not perform sufficient
error checking after executing devm_ioremap_resource(), which can
result in crashes if a critical error path is encountered.
Fixes: 0ae349a0f33f ("iommu/qcom: Add qcom_iommu")
Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20200418134703.1760-1-tangbin@cmss.chinamobile.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Some older compilers like gcc-4.8 warn about mismatched curly braces in
a initializer:
fs/btrfs/backref.c: In function 'is_shared_data_backref':
fs/btrfs/backref.c:394:9: error: missing braces around
initializer [-Werror=missing-braces]
struct prelim_ref target = {0};
^
fs/btrfs/backref.c:394:9: error: (near initialization for
'target.rbnode') [-Werror=missing-braces]
Use the GNU empty initializer extension to avoid this.
Fixes: ed58f2e66e84 ("btrfs: backref, don't add refs from shared block when resolving normal backref")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull iomap fix from Darrick Wong:
"Hoist the check for an unrepresentable FIBMAP return value into
ioctl_fibmap.
The internal kernel function can handle 64-bit values (and is needed
to fix a regression on ext4 + jbd2). It is only the userspace ioctl
that is so old that it cannot deal"
* tag 'iomap-5.7-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
fibmap: Warn and return an error in case of block > INT_MAX
* pm-cpufreq:
cpufreq: intel_pstate: Only mention the BIOS disabling turbo mode once
* pm-sleep:
PM: hibernate: Freeze kernel threads in software_resume()
In commit a7ba5c3d008d ("drivers/iommu: Export core IOMMU API symbols to
permit modular drivers") a bunch of iommu symbols were exported, all
with _GPL markings except iommu_group_get_for_dev(). That export should
also be _GPL like the others.
Fixes: a7ba5c3d008d ("drivers/iommu: Export core IOMMU API symbols to permit modular drivers")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Will Deacon <will@kernel.org>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: John Garry <john.garry@huawei.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200430120120.2948448-1-gregkh@linuxfoundation.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
[BUG]
One run of btrfs/063 triggered the following lockdep warning:
============================================
WARNING: possible recursive locking detected
5.6.0-rc7-custom+ #48 Not tainted
--------------------------------------------
kworker/u24:0/7 is trying to acquire lock:
ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]
but task is already holding lock:
ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(sb_internal#2);
lock(sb_internal#2);
*** DEADLOCK ***
May be due to missing lock nesting notation
4 locks held by kworker/u24:0/7:
#0: ffff88817b495948 ((wq_completion)btrfs-endio-write){+.+.}, at: process_one_work+0x557/0xb80
#1: ffff888189ea7db8 ((work_completion)(&work->normal_work)){+.+.}, at: process_one_work+0x557/0xb80
#2: ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]
#3: ffff888174ca4da8 (&fs_info->reloc_mutex){+.+.}, at: btrfs_record_root_in_trans+0x83/0xd0 [btrfs]
stack backtrace:
CPU: 0 PID: 7 Comm: kworker/u24:0 Not tainted 5.6.0-rc7-custom+ #48
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Workqueue: btrfs-endio-write btrfs_work_helper [btrfs]
Call Trace:
dump_stack+0xc2/0x11a
__lock_acquire.cold+0xce/0x214
lock_acquire+0xe6/0x210
__sb_start_write+0x14e/0x290
start_transaction+0x66c/0x890 [btrfs]
btrfs_join_transaction+0x1d/0x20 [btrfs]
find_free_extent+0x1504/0x1a50 [btrfs]
btrfs_reserve_extent+0xd5/0x1f0 [btrfs]
btrfs_alloc_tree_block+0x1ac/0x570 [btrfs]
btrfs_copy_root+0x213/0x580 [btrfs]
create_reloc_root+0x3bd/0x470 [btrfs]
btrfs_init_reloc_root+0x2d2/0x310 [btrfs]
record_root_in_trans+0x191/0x1d0 [btrfs]
btrfs_record_root_in_trans+0x90/0xd0 [btrfs]
start_transaction+0x16e/0x890 [btrfs]
btrfs_join_transaction+0x1d/0x20 [btrfs]
btrfs_finish_ordered_io+0x55d/0xcd0 [btrfs]
finish_ordered_fn+0x15/0x20 [btrfs]
btrfs_work_helper+0x116/0x9a0 [btrfs]
process_one_work+0x632/0xb80
worker_thread+0x80/0x690
kthread+0x1a3/0x1f0
ret_from_fork+0x27/0x50
It's pretty hard to reproduce, only one hit so far.
[CAUSE]
This is because we're calling btrfs_join_transaction() without re-using
the current running one:
btrfs_finish_ordered_io()
|- btrfs_join_transaction() <<< Call #1
|- btrfs_record_root_in_trans()
|- btrfs_reserve_extent()
|- btrfs_join_transaction() <<< Call #2
Normally such btrfs_join_transaction() call should re-use the existing
one, without trying to re-start a transaction.
But the problem is, in btrfs_join_transaction() call #1, we call
btrfs_record_root_in_trans() before initializing current::journal_info.
And in btrfs_join_transaction() call #2, we're relying on
current::journal_info to avoid such deadlock.
[FIX]
Call btrfs_record_root_in_trans() after we have initialized
current::journal_info.
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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