Using the old mount api to remount an overlayfs superblock via
mount(MS_REMOUNT) all mount options will be silently ignored. For
example, if you create an overlayfs mount:
mount -t overlay overlay -o lowerdir=/mnt/a:/mnt/b,upperdir=/mnt/upper,workdir=/mnt/work /mnt/merged
and then issue a remount via:
# force mount(8) to use mount(2)
export LIBMOUNT_FORCE_MOUNT2=always
mount -t overlay overlay -o remount,WOOTWOOT,lowerdir=/DOESNT-EXIST /mnt/merged
with completely nonsensical mount options whatsoever it will succeed
nonetheless. This prevents us from every changing any mount options we
might introduce in the future that could reasonably be changed during a
remount.
We don't need to carry this issue into the new mount api port. Similar
to FUSE we can use the fs_context::oldapi member to figure out that this
is a request coming through the legacy mount api. If we detect it we
continue silently ignoring all mount options.
But for the new mount api we simply report that mount options cannot
currently be changed. This will allow us to potentially alter mount
properties for new or even old properties. It any case, silently
ignoring everything is not something new apis should do.
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
thread.bad_cause is saved in arch_uprobe_pre_xol(), it should be restored
in arch_uprobe_{post,abort}_xol() accordingly, otherwise the save operation
is meaningless, this change is similar with x86 and powerpc.
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Guo Ren <guoren@kernel.org>
Fixes: 74784081aa ("riscv: Add uprobes supported")
Link: https://lore.kernel.org/r/1682214146-3756-1-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Attempt VMA lock-based page fault handling first, and fall back to the
existing mmap_lock-based handling if that fails.
A simple running the ebizzy benchmark on Lichee Pi 4A shows that
PER_VMA_LOCK can improve the ebizzy benchmark by about 32.68%. In
theory, the more CPUs, the bigger improvement, but I don't have any
HW platform which has more than 4 CPUs.
This is the riscv variant of "x86/mm: try VMA lock-based page fault
handling first".
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Link: https://lore.kernel.org/r/20230523165942.2630-1-jszhang@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
When probing for an ACPI-specified IPMI device, the code would request
that the acpi_ipmi module be loaded ACPI operations through IPMI can be
performed. This could happen through module load context, for instance,
if an I2C module is loaded that caused the IPMI interface to be probed.
This is not allowed because a synchronous module load in this context
can result in an deadlock, and I was getting a warning:
[ 23.967853] WARNING: CPU: 0 PID: 21 at kernel/module/kmod.c:144 __request_module+0x1de/0x2d0
[ 23.968852] Modules linked in: i2c_i801 ipmi_ssif
The IPMI driver is not dependent on acpi_ipmi, so just change the called
to request_module_nowait to make the load asynchronous.
Signed-off-by: Corey Minyard <minyard@acm.org>
Cleanup bindings dropping unneeded quotes. Once all these are fixed,
checking for this can be enabled in yamllint. Also absolute path
starting with /schemas is preferred.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230609140754.65158-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Rob Herring <robh@kernel.org>
Cleanup bindings dropping unneeded quotes. Once all these are fixed,
checking for this can be enabled in yamllint. Also absolute path
starting with /schemas is preferred.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230609140749.65102-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Rob Herring <robh@kernel.org>
Now that the driver core allows for struct class to be in read-only
memory, move the ipmi_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at boot time.
Cc: Corey Minyard <minyard@acm.org>
Cc: openipmi-developer@lists.sourceforge.net
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Message-Id: <20230620143701.577657-2-gregkh@linuxfoundation.org>
Signed-off-by: Corey Minyard <minyard@acm.org>
A recent patch incorrectly did not include IB_ACCESS_RELAXED_ORDERING in
the list of supported access flags for the rxe driver. The driver actually
does nothing related to relaxed ordering but it causes no problems to
include it as supported but with no effect. This change caused ib_send_bw
and friends to not run correctly.
The correct approach is for the driver to allow any of the optional access
flags and otherwise ignore them. This patch adds IB_ACCESS_OPTIONAL to the
list of rxe supported flags.
Fixes: 02ed253770 ("RDMA/rxe: Introduce rxe access supported flags")
Link: https://lore.kernel.org/r/20230613171654.19334-1-rpearsonhpe@gmail.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Cleanup bindings dropping unneeded quotes. Once all these are fixed,
checking for this can be enabled in yamllint.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20230609140655.64529-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Rob Herring <robh@kernel.org>
The current way how lowcomms is configured is due configfs entries. Each
comms configfs entry will create a lowcomms connection. Even the local
connection itself will be stored as a lowcomms connection, although most
functionality for a local lowcomms connection struct is not necessary.
Now in some scenarios we will see that dlm_controld reports a -EEXIST
when configure a node via configfs:
... /sys/kernel/config/dlm/cluster/comms/1/addr: write failed: 17 -1
Doing a:
cat /sys/kernel/config/dlm/cluster/comms/1/addr_list
reported nothing. This was being seen on cluster with nodeid 1 and it's
local configuration. To be sure the configfs entries are in sync with
lowcomms connection structures we always call dlm_midcomms_close() to be
sure the lowcomms connection gets removed when the configfs entry gets
dropped.
Before commit 07ee38674a ("fs: dlm: filter ourself midcomms calls") it
was just doing this by accident and the filter by doing:
if (nodeid == dlm_our_nodeid())
return 0;
inside dlm_midcomms_close() was never been hit because drop_comm() sets
local_comm to NULL and cause that dlm_our_nodeid() returns always the
invalid nodeid 0.
Fixes: 07ee38674a ("fs: dlm: filter ourself midcomms calls")
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
There is a spelling mistake in a dev_err message. Fix it. Also fix
grammar and add space between last word and (%d)".
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20230620095620.2522058-1-colin.i.king@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Merge series from Srinivas Kandagatla <srinivas.kandagatla@linaro.org>:
This patchset adds compressed offload support to Qualcomm audioreach drivers.
Currently it supports AAC, MP3 and FALC along with gapless.
Tested this on SM8450 and sc7280.
Merge series from Mark Brown <broonie@kernel.org>:
Several of the Everest Semi CODECs only support single register read and
write operations and therefore do not benefit from using the rbtree
cache over the maple tree cache, convert them to the more modern maple
tree cache.
Merge series from Mark Brown <broonie@kernel.org>:
Many of the Realtek I2C/SPI devices only support single register read
and write operations so don't benefit from using the rbtree cache
instead of the more modern maple tree cache, convert them to maple tree.
Now that the driver core allows for struct class to be in read-only
memory, move the hidg_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at load time.
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Link: https://lore.kernel.org/r/20230620094412.508580-11-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that the driver core allows for struct class to be in read-only
memory, move the usb_gadget_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at load time.
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Link: https://lore.kernel.org/r/20230620094412.508580-10-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that the driver core allows for struct class to be in read-only
memory, move the mon_bin_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at load time.
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Link: https://lore.kernel.org/r/20230620094412.508580-9-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that the driver core allows for struct class to be in read-only
memory, move the udc_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at load time.
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Link: https://lore.kernel.org/r/20230620094412.508580-8-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that the driver core allows for struct class to be in read-only
memory, move the role_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at load time.
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Link: https://lore.kernel.org/r/20230620094412.508580-7-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The hibernation feature enabled for Xilinx Versal NET SoC in DWC3 IP.
As the DWC3 IP supports the hibernation feature, to handle the wakeup
or hibernation interrupt, add host mode "wakeup" interrupt-names
optional property in the binding schema to capture remote-wakeup and
connect/ disconnect event in the hibernation state and increased maxItems
to 4 for the interrupts and interrupt-names property.
We have a dedicated IRQ line specifically for the hibernation feature.
When the "wakeup" IRQ line is triggered, it initiates a hibernation
interrupt, causing the system to wake up from the hibernation state.
Signed-off-by: Piyush Mehta <piyush.mehta@amd.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230619105032.2888128-1-piyush.mehta@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In previous patches we removed 5G code since the hardware that uses this
driver does not support 5G. There is still some 5G related code, remove it.
All the removed defines are unused and we can safely remove "N-5G" from the
rtllib_modes array.
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/20230619155203.6039-1-straube.linux@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove a comparison to true reported by checkpatch.
CHECK: Using comparison to true is error prone
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/20230619150953.22484-5-straube.linux@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove unnecessary return statement from the void function
rtl92e_config_mac(). Issue found by checkpatch.
WARNING: void function return statements are not generally useful
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/20230619150953.22484-4-straube.linux@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Convert a sequence of else if statements that all check the same
variable to a single switch statement. With a switch statement it is
easier to see what is going on. Additionally this clears a checkpatch
warning.
WARNING: braces {} are not necessary for any arm of this statement
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/20230619150953.22484-3-straube.linux@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Clean up brace coding style in if/else statements to improve
readability and clear checkpatch issues.
CHECK: braces {} should be used on all arms of this statement
CHECK: Unbalanced braces around else statement
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/20230619150953.22484-2-straube.linux@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix the following checkpatch blank line issues:
- CHECK: Please don't use multiple blank lines
- CHECK: Blank lines aren't necessary before a close brace '}'
- CHECK: Blank lines aren't necessary after an open brace '{'
Signed-off-by: Franziska Naepelt <franziska.naepelt@gmail.com>
Link: https://lore.kernel.org/r/20230619181246.19112-1-franziska.naepelt@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Additional declaration of struct vchiq_instance was introduced in the
commit 726e79f8a6 ("staging: vchiq_arm: pass vchiq instance to
service callbacks"). Drop the extra declaration.
Fixes: 726e79f8a6 ("staging: vchiq_arm: pass vchiq instance to service callbacks")
Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Link: https://lore.kernel.org/r/20221221074047.233473-1-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
smatch warning:
drivers/accel/qaic/qaic_data.c:620 qaic_free_object() error:
dereferencing freed memory 'obj->import_attach'
obj->import_attach is detached and freed using dma_buf_detach().
But used after free to decrease the dmabuf ref count using
dma_buf_put().
drm_prime_gem_destroy() handles this issue and performs the proper clean
up instead of open coding it in the driver.
Fixes: ff13be8303 ("accel/qaic: Add datapath")
Reported-by: Sukrut Bellary <sukrut.bellary@linux.com>
Closes: https://lore.kernel.org/all/20230610021200.377452-1-sukrut.bellary@linux.com/
Suggested-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Pranjal Ramajor Asha Kanojiya <quic_pkanojiy@quicinc.com>
Reviewed-by: Carl Vanderlip <quic_carlv@quicinc.com>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230614161528.11710-1-quic_jhugo@quicinc.com
In journal_init_dev(), if super bdev is used as 'j_dev_bd', then
blkdev_get_by_dev() is called with NULL holder, otherwise, holder will
be journal. However, later in release_journal_dev(), blkdev_put() is
called with journal unconditionally, cause following warning:
WARNING: CPU: 1 PID: 5034 at block/bdev.c:617 bd_end_claim block/bdev.c:617 [inline]
WARNING: CPU: 1 PID: 5034 at block/bdev.c:617 blkdev_put+0x562/0x8a0 block/bdev.c:901
RIP: 0010:blkdev_put+0x562/0x8a0 block/bdev.c:901
Call Trace:
<TASK>
release_journal_dev fs/reiserfs/journal.c:2592 [inline]
free_journal_ram+0x421/0x5c0 fs/reiserfs/journal.c:1896
do_journal_release fs/reiserfs/journal.c:1960 [inline]
journal_release+0x276/0x630 fs/reiserfs/journal.c:1971
reiserfs_put_super+0xe4/0x5c0 fs/reiserfs/super.c:616
generic_shutdown_super+0x158/0x480 fs/super.c:499
kill_block_super+0x64/0xb0 fs/super.c:1422
deactivate_locked_super+0x98/0x160 fs/super.c:330
deactivate_super+0xb1/0xd0 fs/super.c:361
cleanup_mnt+0x2ae/0x3d0 fs/namespace.c:1247
task_work_run+0x16f/0x270 kernel/task_work.c:179
exit_task_work include/linux/task_work.h:38 [inline]
do_exit+0xadc/0x2a30 kernel/exit.c:874
do_group_exit+0xd4/0x2a0 kernel/exit.c:1024
__do_sys_exit_group kernel/exit.c:1035 [inline]
__se_sys_exit_group kernel/exit.c:1033 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1033
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Fix this problem by passing in NULL holder in this case.
Reported-by: syzbot+04625c80899f4555de39@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=04625c80899f4555de39
Fixes: 2736e8eeb0 ("block: use the holder as indication for exclusive opens")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230620111322.1014775-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
After commit 2736e8eeb0 ("block: use the holder as indication for
exclusive opens"), blkdev_get_by_dev() will warn if holder is NULL and
mode contains 'FMODE_EXCL'.
holder from blkdev_get_by_dev() from disk_scan_partitions() is always NULL,
hence it should not use 'FMODE_EXCL', which is broben by the commit. For
consequence, WARN_ON_ONCE() will be triggered from blkdev_get_by_dev()
if user scan partitions with device opened exclusively.
Fix this problem by removing 'FMODE_EXCL' from disk_scan_partitions(),
as it used to be.
Reported-by: syzbot+00cd27751f78817f167b@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=00cd27751f78817f167b
Fixes: 2736e8eeb0 ("block: use the holder as indication for exclusive opens")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230618140402.7556-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, associating a loop device with a different file descriptor
does not increment its diskseq. This allows the following race
condition:
1. Program X opens a loop device
2. Program X gets the diskseq of the loop device.
3. Program X associates a file with the loop device.
4. Program X passes the loop device major, minor, and diskseq to
something.
5. Program X exits.
6. Program Y detaches the file from the loop device.
7. Program Y attaches a different file to the loop device.
8. The opener finally gets around to opening the loop device and checks
that the diskseq is what it expects it to be. Even though the
diskseq is the expected value, the result is that the opener is
accessing the wrong file.
From discussions with Christoph Hellwig, it appears that
disk_force_media_change() was supposed to call inc_diskseq(), but in
fact it does not. Adding a Fixes: tag to indicate this. Christoph's
Reported-by is because he stated that disk_force_media_change()
calls inc_diskseq(), which is what led me to discover that it should but
does not.
Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Demi Marie Obenour <demi@invisiblethingslab.com>
Fixes: e6138dc12d ("block: add a helper to raise a media changed event")
Cc: stable@vger.kernel.org # 5.15+
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230607170837.1559-1-demi@invisiblethingslab.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Fix a missing conversion to the new BLK_OPEN constant in swim.
Fixes: 05bdb99653 ("block: replace fmode_t with a block-specific type for block open flags")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230620043051.707196-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Parking CPUs in a HLT loop is not completely safe vs. kexec() as HLT can
resume execution due to NMI, SMI and MCE, which has the same issue as the
MWAIT loop.
Kicking the secondary CPUs into INIT makes this safe against NMI and SMI.
A broadcast MCE will take the machine down, but a broadcast MCE which makes
HLT resume and execute overwritten text, pagetables or data will end up in
a disaster too.
So chose the lesser of two evils and kick the secondary CPUs into INIT
unless the system has installed special wakeup mechanisms which are not
using INIT.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230615193330.608657211@linutronix.de
Putting CPUs into INIT is a safer place during kexec() to park CPUs.
Split the INIT assert/deassert sequence out so it can be reused.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Link: https://lore.kernel.org/r/20230615193330.551157083@linutronix.de
TLDR: It's a mess.
When kexec() is executed on a system with offline CPUs, which are parked in
mwait_play_dead() it can end up in a triple fault during the bootup of the
kexec kernel or cause hard to diagnose data corruption.
The reason is that kexec() eventually overwrites the previous kernel's text,
page tables, data and stack. If it writes to the cache line which is
monitored by a previously offlined CPU, MWAIT resumes execution and ends
up executing the wrong text, dereferencing overwritten page tables or
corrupting the kexec kernels data.
Cure this by bringing the offlined CPUs out of MWAIT into HLT.
Write to the monitored cache line of each offline CPU, which makes MWAIT
resume execution. The written control word tells the offlined CPUs to issue
HLT, which does not have the MWAIT problem.
That does not help, if a stray NMI, MCE or SMI hits the offlined CPUs as
those make it come out of HLT.
A follow up change will put them into INIT, which protects at least against
NMI and SMI.
Fixes: ea53069231 ("x86, hotplug: Use mwait to offline a processor, fix the legacy case")
Reported-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230615193330.492257119@linutronix.de
Monitoring idletask::thread_info::flags in mwait_play_dead() has been an
obvious choice as all what is needed is a cache line which is not written
by other CPUs.
But there is a use case where a "dead" CPU needs to be brought out of
MWAIT: kexec().
This is required as kexec() can overwrite text, pagetables, stacks and the
monitored cacheline of the original kernel. The latter causes MWAIT to
resume execution which obviously causes havoc on the kexec kernel which
results usually in triple faults.
Use a dedicated per CPU storage to prepare for that.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230615193330.434553750@linutronix.de
The wmb()s before sending the IPIs are not synchronizing anything.
If at all then the apic IPI functions have to provide or act as appropriate
barriers.
Remove these cargo cult barriers which have no explanation of what they are
synchronizing.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230615193330.378358382@linutronix.de
stop_this_cpu() tests CPUID leaf 0x8000001f::EAX unconditionally. Intel
CPUs return the content of the highest supported leaf when a non-existing
leaf is read, while AMD CPUs return all zeros for unsupported leafs.
So the result of the test on Intel CPUs is lottery.
While harmless it's incorrect and causes the conditional wbinvd() to be
issued where not required.
Check whether the leaf is supported before reading it.
[ tglx: Adjusted changelog ]
Fixes: 08f253ec37 ("x86/cpu: Clear SME feature flag when not in use")
Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/3817d810-e0f1-8ef8-0bbd-663b919ca49b@cybernetics.com
Link: https://lore.kernel.org/r/20230615193330.322186388@linutronix.de
Tony reported intermittent lockups on poweroff. His analysis identified the
wbinvd() in stop_this_cpu() as the culprit. This was added to ensure that
on SME enabled machines a kexec() does not leave any stale data in the
caches when switching from encrypted to non-encrypted mode or vice versa.
That wbinvd() is conditional on the SME feature bit which is read directly
from CPUID. But that readout does not check whether the CPUID leaf is
available or not. If it's not available the CPU will return the value of
the highest supported leaf instead. Depending on the content the "SME" bit
might be set or not.
That's incorrect but harmless. Making the CPUID readout conditional makes
the observed hangs go away, but it does not fix the underlying problem:
CPU0 CPU1
stop_other_cpus()
send_IPIs(REBOOT); stop_this_cpu()
while (num_online_cpus() > 1); set_online(false);
proceed... -> hang
wbinvd()
WBINVD is an expensive operation and if multiple CPUs issue it at the same
time the resulting delays are even larger.
But CPU0 already observed num_online_cpus() going down to 1 and proceeds
which causes the system to hang.
This issue exists independent of WBINVD, but the delays caused by WBINVD
make it more prominent.
Make this more robust by adding a cpumask which is initialized to the
online CPU mask before sending the IPIs and CPUs clear their bit in
stop_this_cpu() after the WBINVD completed. Check for that cpumask to
become empty in stop_other_cpus() instead of watching num_online_cpus().
The cpumask cannot plug all holes either, but it's better than a raw
counter and allows to restrict the NMI fallback IPI to be sent only the
CPUs which have not reported within the timeout window.
Fixes: 08f253ec37 ("x86/cpu: Clear SME feature flag when not in use")
Reported-by: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/3817d810-e0f1-8ef8-0bbd-663b919ca49b@cybernetics.com
Link: https://lore.kernel.org/r/87h6r770bv.ffs@tglx
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new() which already returns void. Eventually after all drivers
are converted, .remove_new() is renamed to .remove().
Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.
While destroying alignment of the assignments in bridge_driver, do it
consistently and use a single space before =.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
