Having multiple versions of on_accessible_stack() (one per unwinder)
makes it very hard to reason about what is used where due to the
complexity of the various includes, the forward declarations, and
the reliance on everything being 'inline'.
Instead, move the code back where it should be. Each unwinder
implements:
- on_accessible_stack() as well as the helpers it depends on,
- unwind()/unwind_next(), as they pass on_accessible_stack as
a parameter to unwind_next_common() (which is the only common
code here)
This hardly results in any duplication, and makes it much
easier to reason about the code.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Kalesh Singh <kaleshsingh@google.com>
Tested-by: Kalesh Singh <kaleshsingh@google.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20220727142906.1856759-4-maz@kernel.org
Implements the common framework necessary for unwind() to work in
the protected nVHE context:
- on_accessible_stack()
- on_overflow_stack()
- unwind_next()
Protected nVHE unwind() is used to unwind and save the hyp stack
addresses to the shared stacktrace buffer. The host reads the
entries in this buffer, symbolizes and dumps the stacktrace (later
patch in the series).
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220726073750.3219117-17-kaleshsingh@google.com
In protected nVHE mode, the host cannot access private owned hypervisor
memory. Also the hypervisor aims to remains simple to reduce the attack
surface and does not provide any printk support.
For the above reasons, the approach taken to provide hypervisor stacktraces
in protected mode is:
1) Unwind and save the hyp stack addresses in EL2 to a shared buffer
with the host (done in this patch).
2) Delegate the dumping and symbolization of the addresses to the
host in EL1 (later patch in the series).
On hyp_panic(), the hypervisor prepares the stacktrace before returning to
the host.
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220726073750.3219117-16-kaleshsingh@google.com
In protected nVHE mode the host cannot directly access
hypervisor memory, so we will dump the hypervisor stacktrace
to a shared buffer with the host.
The minimum size for the buffer required, assuming the min frame
size of [x29, x30] (2 * sizeof(long)), is half the combined size of
the hypervisor and overflow stacks plus an additional entry to
delimit the end of the stacktrace.
The stacktrace buffers are used later in the series to dump the
nVHE hypervisor stacktrace when using protected-mode.
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220726073750.3219117-14-kaleshsingh@google.com
In non-protected nVHE mode (non-pKVM) the host can directly access
hypervisor memory; and unwinding of the hypervisor stacktrace is
done from EL1 to save on memory for shared buffers.
To unwind the hypervisor stack from EL1 the host needs to know the
starting point for the unwind and information that will allow it to
translate hypervisor stack addresses to the corresponding kernel
addresses. This patch sets up this book keeping. It is made use of
later in the series.
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220726073750.3219117-10-kaleshsingh@google.com
The unwinder code is made reusable so that it can be used to
unwind various types of stacks. One usecase is unwinding the
nVHE hyp stack from the host (EL1) in non-protected mode. This
means that the unwinder must be able to translate HYP stack
addresses to kernel addresses.
Add a callback (stack_trace_translate_fp_fn) to allow specifying
the translation function.
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220726073750.3219117-5-kaleshsingh@google.com
unwind_init() is currently a single function that initializes all of the
unwind state. Split it into the following functions and call them
appropriately:
- unwind_init_from_regs() - initialize from regs passed by caller.
- unwind_init_from_caller() - initialize for the current task
from the caller of arch_stack_walk().
- unwind_init_from_task() - initialize from the saved state of a
task other than the current task. In this case, the other
task must not be running.
This is done for two reasons:
- the different ways of initializing are clear
- specialized code can be added to each initializer in the future.
Signed-off-by: Madhavan T. Venkataraman <madvenka@linux.microsoft.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220617180219.20352-2-madvenka@linux.microsoft.com
Signed-off-by: Will Deacon <will@kernel.org>
Pull x86 fixes from Thomas Gleixner:
- Make RESERVE_BRK() work again with older binutils. The recent
'simplification' broke that.
- Make early #VE handling increment RIP when successful.
- Make the #VE code consistent vs. the RIP adjustments and add
comments.
- Handle load_unaligned_zeropad() across page boundaries correctly in
#VE when the second page is shared.
* tag 'x86-urgent-2022-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tdx: Handle load_unaligned_zeropad() page-cross to a shared page
x86/tdx: Clarify RIP adjustments in #VE handler
x86/tdx: Fix early #VE handling
x86/mm: Fix RESERVE_BRK() for older binutils
Pull build tooling updates from Thomas Gleixner:
- Remove obsolete CONFIG_X86_SMAP reference from objtool
- Fix overlapping text section failures in faddr2line for real
- Remove OBJECT_FILES_NON_STANDARD usage from x86 ftrace and replace it
with finegrained annotations so objtool can validate that code
correctly.
* tag 'objtool-urgent-2022-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/ftrace: Remove OBJECT_FILES_NON_STANDARD usage
faddr2line: Fix overlapping text section failures, the sequel
objtool: Fix obsolete reference to CONFIG_X86_SMAP
Pull scheduler fix from Thomas Gleixner:
"A single scheduler fix plugging a race between sched_setscheduler()
and balance_push().
sched_setscheduler() spliced the balance callbacks accross a lock
break which makes it possible for an interleaving schedule() to
observe an empty list"
* tag 'sched-urgent-2022-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Fix balance_push() vs __sched_setscheduler()
Pull lockdep fix from Thomas Gleixner:
"A RT fix for lockdep.
lockdep invokes prandom_u32() to create cookies. This worked until
prandom_u32() was switched to the real random generator, which takes a
spinlock for extraction, which does not work on RT when invoked from
atomic contexts.
lockdep has no requirement for real random numbers and it turns out
sched_clock() is good enough to create the cookie. That works
everywhere and is faster"
* tag 'locking-urgent-2022-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/lockdep: Use sched_clock() for random numbers
Pull irq fixes from Thomas Gleixner:
"A set of interrupt subsystem updates:
Core:
- Ensure runtime power management for chained interrupts
Drivers:
- A collection of OF node refcount fixes
- Unbreak MIPS uniprocessor builds
- Fix xilinx interrupt controller Kconfig dependencies
- Add a missing compatible string to the Uniphier driver"
* tag 'irq-urgent-2022-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/loongson-liointc: Use architecture register to get coreid
irqchip/uniphier-aidet: Add compatible string for NX1 SoC
dt-bindings: interrupt-controller/uniphier-aidet: Add bindings for NX1 SoC
irqchip/realtek-rtl: Fix refcount leak in map_interrupts
irqchip/gic-v3: Fix refcount leak in gic_populate_ppi_partitions
irqchip/gic-v3: Fix error handling in gic_populate_ppi_partitions
irqchip/apple-aic: Fix refcount leak in aic_of_ic_init
irqchip/apple-aic: Fix refcount leak in build_fiq_affinity
irqchip/gic/realview: Fix refcount leak in realview_gic_of_init
irqchip/xilinx: Remove microblaze+zynq dependency
genirq: PM: Use runtime PM for chained interrupts
Pull char/misc driver fixes for real from Greg KH:
"Let's tag the proper branch this time...
Here are some small char/misc driver fixes for 5.19-rc3 that resolve
some reported issues.
They include:
- mei driver fixes
- comedi driver fix
- rtsx build warning fix
- fsl-mc-bus driver fix
All of these have been in linux-next for a while with no reported
issues"
This is what the merge in commit f0ec9c65a8 _should_ have merged, but
Greg fat-fingered the pull request and I got some small changes from
linux-next instead there. Credit to Nathan Chancellor for eagle-eyes.
Link: https://lore.kernel.org/all/Yqywy+Md2AfGDu8v@dev-arch.thelio-3990X/
* tag 'char-misc-5.19-rc3-take2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
bus: fsl-mc-bus: fix KASAN use-after-free in fsl_mc_bus_remove()
mei: me: add raptor lake point S DID
mei: hbm: drop capability response on early shutdown
mei: me: set internal pg flag to off on hardware reset
misc: rtsx: Fix clang -Wsometimes-uninitialized in rts5261_init_from_hw()
comedi: vmk80xx: fix expression for tx buffer size
Pull i2c fixes from Wolfram Sang:
"MAINTAINERS rectifications and a few minor driver fixes"
* tag 'i2c-for-5.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: mediatek: Fix an error handling path in mtk_i2c_probe()
i2c: designware: Use standard optional ref clock implementation
MAINTAINERS: core DT include belongs to core
MAINTAINERS: add include/dt-bindings/i2c to I2C SUBSYSTEM HOST DRIVERS
i2c: npcm7xx: Add check for platform_driver_register
MAINTAINERS: Update Synopsys DesignWare I2C to Supported
Pull xfs fixes from Darrick Wong:
"There's not a whole lot this time around (I'm still on vacation) but
here are some important fixes for new features merged in -rc1:
- Fix a bug where inode flag changes would accidentally drop nrext64
- Fix a race condition when toggling LARP mode"
* tag 'xfs-5.19-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: preserve DIFLAG2_NREXT64 when setting other inode attributes
xfs: fix variable state usage
xfs: fix TOCTOU race involving the new logged xattrs control knob
Pull ext4 fixes from Ted Ts'o:
"Fix a variety of bugs, many of which were found by folks using fuzzing
or error injection.
Also fix up how test_dummy_encryption mount option is handled for the
new mount API.
Finally, fix/cleanup a number of comments and ext4 Documentation
files"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix a doubled word "need" in a comment
ext4: add reserved GDT blocks check
ext4: make variable "count" signed
ext4: correct the judgment of BUG in ext4_mb_normalize_request
ext4: fix bug_on ext4_mb_use_inode_pa
ext4: fix up test_dummy_encryption handling for new mount API
ext4: use kmemdup() to replace kmalloc + memcpy
ext4: fix super block checksum incorrect after mount
ext4: improve write performance with disabled delalloc
ext4: fix warning when submitting superblock in ext4_commit_super()
ext4, doc: remove unnecessary escaping
ext4: fix incorrect comment in ext4_bio_write_page()
fs: fix jbd2_journal_try_to_free_buffers() kernel-doc comment
Pull cifs client fixes from Steve French:
"Two cifs debugging improvements - one found to deal with debugging a
multichannel problem and one for a recent fallocate issue
This does include the two larger multichannel reconnect (dynamically
adjusting interfaces on reconnect) patches, because we recently found
an additional problem with multichannel to one server type that I want
to include at the same time"
* tag '5.19-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: when a channel is not found for server, log its connection id
smb3: add trace point for SMB2_set_eof
We capture a NULL pointer issue when resizing a corrupt ext4 image which
is freshly clear resize_inode feature (not run e2fsck). It could be
simply reproduced by following steps. The problem is because of the
resize_inode feature was cleared, and it will convert the filesystem to
meta_bg mode in ext4_resize_fs(), but the es->s_reserved_gdt_blocks was
not reduced to zero, so could we mistakenly call reserve_backup_gdb()
and passing an uninitialized resize_inode to it when adding new group
descriptors.
mkfs.ext4 /dev/sda 3G
tune2fs -O ^resize_inode /dev/sda #forget to run requested e2fsck
mount /dev/sda /mnt
resize2fs /dev/sda 8G
========
BUG: kernel NULL pointer dereference, address: 0000000000000028
CPU: 19 PID: 3243 Comm: resize2fs Not tainted 5.18.0-rc7-00001-gfde086c5ebfd #748
...
RIP: 0010:ext4_flex_group_add+0xe08/0x2570
...
Call Trace:
<TASK>
ext4_resize_fs+0xbec/0x1660
__ext4_ioctl+0x1749/0x24e0
ext4_ioctl+0x12/0x20
__x64_sys_ioctl+0xa6/0x110
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f2dd739617b
========
The fix is simple, add a check in ext4_resize_begin() to make sure that
the es->s_reserved_gdt_blocks is zero when the resize_inode feature is
disabled.
Cc: stable@kernel.org
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Ritesh Harjani <ritesh.list@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220601092717.763694-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_mb_normalize_request() can move logical start of allocated blocks
to reduce fragmentation and better utilize preallocation. However logical
block requested as a start of allocation (ac->ac_o_ex.fe_logical) should
always be covered by allocated blocks so we should check that by
modifying and to or in the assertion.
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Ritesh Harjani <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/20220528110017.354175-3-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Hulk Robot reported a BUG_ON:
==================================================================
kernel BUG at fs/ext4/mballoc.c:3211!
[...]
RIP: 0010:ext4_mb_mark_diskspace_used.cold+0x85/0x136f
[...]
Call Trace:
ext4_mb_new_blocks+0x9df/0x5d30
ext4_ext_map_blocks+0x1803/0x4d80
ext4_map_blocks+0x3a4/0x1a10
ext4_writepages+0x126d/0x2c30
do_writepages+0x7f/0x1b0
__filemap_fdatawrite_range+0x285/0x3b0
file_write_and_wait_range+0xb1/0x140
ext4_sync_file+0x1aa/0xca0
vfs_fsync_range+0xfb/0x260
do_fsync+0x48/0xa0
[...]
==================================================================
Above issue may happen as follows:
-------------------------------------
do_fsync
vfs_fsync_range
ext4_sync_file
file_write_and_wait_range
__filemap_fdatawrite_range
do_writepages
ext4_writepages
mpage_map_and_submit_extent
mpage_map_one_extent
ext4_map_blocks
ext4_mb_new_blocks
ext4_mb_normalize_request
>>> start + size <= ac->ac_o_ex.fe_logical
ext4_mb_regular_allocator
ext4_mb_simple_scan_group
ext4_mb_use_best_found
ext4_mb_new_preallocation
ext4_mb_new_inode_pa
ext4_mb_use_inode_pa
>>> set ac->ac_b_ex.fe_len <= 0
ext4_mb_mark_diskspace_used
>>> BUG_ON(ac->ac_b_ex.fe_len <= 0);
we can easily reproduce this problem with the following commands:
`fallocate -l100M disk`
`mkfs.ext4 -b 1024 -g 256 disk`
`mount disk /mnt`
`fsstress -d /mnt -l 0 -n 1000 -p 1`
The size must be smaller than or equal to EXT4_BLOCKS_PER_GROUP.
Therefore, "start + size <= ac->ac_o_ex.fe_logical" may occur
when the size is truncated. So start should be the start position of
the group where ac_o_ex.fe_logical is located after alignment.
In addition, when the value of fe_logical or EXT4_BLOCKS_PER_GROUP
is very large, the value calculated by start_off is more accurate.
Cc: stable@kernel.org
Fixes: cd648b8a8f ("ext4: trim allocation requests to group size")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Ritesh Harjani <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/20220528110017.354175-2-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Since ext4 was converted to the new mount API, the test_dummy_encryption
mount option isn't being handled entirely correctly, because the needed
fscrypt_set_test_dummy_encryption() helper function combines
parsing/checking/applying into one function. That doesn't work well
with the new mount API, which split these into separate steps.
This was sort of okay anyway, due to the parsing logic that was copied
from fscrypt_set_test_dummy_encryption() into ext4_parse_param(),
combined with an additional check in ext4_check_test_dummy_encryption().
However, these overlooked the case of changing the value of
test_dummy_encryption on remount, which isn't allowed but ext4 wasn't
detecting until ext4_apply_options() when it's too late to fail.
Another bug is that if test_dummy_encryption was specified multiple
times with an argument, memory was leaked.
Fix this up properly by using the new helper functions that allow
splitting up the parse/check/apply steps for test_dummy_encryption.
Fixes: cebe85d570 ("ext4: switch to the new mount api")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20220526040412.173025-1-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
We got issue as follows:
[home]# mount /dev/sda test
EXT4-fs (sda): warning: mounting fs with errors, running e2fsck is recommended
[home]# dmesg
EXT4-fs (sda): warning: mounting fs with errors, running e2fsck is recommended
EXT4-fs (sda): Errors on filesystem, clearing orphan list.
EXT4-fs (sda): recovery complete
EXT4-fs (sda): mounted filesystem with ordered data mode. Quota mode: none.
[home]# debugfs /dev/sda
debugfs 1.46.5 (30-Dec-2021)
Checksum errors in superblock! Retrying...
Reason is ext4_orphan_cleanup will reset ‘s_last_orphan’ but not update
super block checksum.
To solve above issue, defer update super block checksum after
ext4_orphan_cleanup.
Signed-off-by: Ye Bin <yebin10@huawei.com>
Cc: stable@kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ritesh Harjani <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/20220525012904.1604737-1-yebin10@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
cifs_ses_get_chan_index gets the index for a given server pointer.
When a match is not found, we warn about a possible bug.
However, printing details about the non-matching server could be
more useful to debug here.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
load_unaligned_zeropad() can lead to unwanted loads across page boundaries.
The unwanted loads are typically harmless. But, they might be made to
totally unrelated or even unmapped memory. load_unaligned_zeropad()
relies on exception fixup (#PF, #GP and now #VE) to recover from these
unwanted loads.
In TDX guests, the second page can be shared page and a VMM may configure
it to trigger #VE.
The kernel assumes that #VE on a shared page is an MMIO access and tries to
decode instruction to handle it. In case of load_unaligned_zeropad() it
may result in confusion as it is not MMIO access.
Fix it by detecting split page MMIO accesses and failing them.
load_unaligned_zeropad() will recover using exception fixups.
The issue was discovered by analysis and reproduced artificially. It was
not triggered during testing.
[ dhansen: fix up changelogs and comments for grammar and clarity,
plus incorporate Kirill's off-by-one fix]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20220614120135.14812-4-kirill.shutemov@linux.intel.com
Pull NFS client fixes from Anna Schumaker:
- Add FMODE_CAN_ODIRECT support to NFSv4 so opens don't fail
- Fix trunking detection & cl_max_connect setting
- Avoid pnfs_update_layout() livelocks
- Don't keep retrying pNFS if the server replies with NFS4ERR_UNAVAILABLE
* tag 'nfs-for-5.19-2' of git://git.linux-nfs.org/projects/anna/linux-nfs:
NFSv4: Add FMODE_CAN_ODIRECT after successful open of a NFS4.x file
sunrpc: set cl_max_connect when cloning an rpc_clnt
pNFS: Avoid a live lock condition in pnfs_update_layout()
pNFS: Don't keep retrying if the server replied NFS4ERR_LAYOUTUNAVAILABLE
Pull pci fix from Bjorn Helgaas:
"Revert clipping of PCI host bridge windows to avoid E820 regions,
which broke several machines by forcing unnecessary BAR reassignments
(Hans de Goede)"
* tag 'pci-v5.19-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
x86/PCI: Revert "x86/PCI: Clip only host bridge windows for E820 regions"
Pull printk fixes from Petr Mladek:
"Make the global console_sem available for CPU that is handling panic()
or shutdown.
This is an old problem when an existing console lock owner might block
console output, but it became more visible with the kthreads"
* tag 'printk-for-5.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
printk: Wait for the global console lock when the system is going down
printk: Block console kthreads when direct printing will be required