KVM: x86: Allow guest to set EFER.NX=1 on non-PAE 32-bit kernels
Remove an ancient restriction that disallowed exposing EFER.NX to the
guest if EFER.NX=0 on the host, even if NX is fully supported by the CPU.
The motivation of the check, added by commit 2cc51560aed0 ("KVM: VMX:
Avoid saving and restoring msr_efer on lightweight vmexit"), was to rule
out the case of host.EFER.NX=0 and guest.EFER.NX=1 so that KVM could run
the guest with the host's EFER.NX and thus avoid context switching EFER
if the only divergence was the NX bit.
Fast forward to today, and KVM has long since stopped running the guest
with the host's EFER.NX. Not only does KVM context switch EFER if
host.EFER.NX=1 && guest.EFER.NX=0, KVM also forces host.EFER.NX=0 &&
guest.EFER.NX=1 when using shadow paging (to emulate SMEP). Furthermore,
the entire motivation for the restriction was made obsolete over a decade
ago when Intel added dedicated host and guest EFER fields in the VMCS
(Nehalem timeframe), which reduced the overhead of context switching EFER
from 400+ cycles (2 * WRMSR + 1 * RDMSR) to a mere ~2 cycles.
In practice, the removed restriction only affects non-PAE 32-bit kernels,
as EFER.NX is set during boot if NX is supported and the kernel will use
PAE paging (32-bit or 64-bit), regardless of whether or not the kernel
will actually use NX itself (mark PTEs non-executable).
Alternatively and/or complementarily, startup_32_smp() in head_32.S could
be modified to set EFER.NX=1 regardless of paging mode, thus eliminating
the scenario where NX is supported but not enabled. However, that runs
the risk of breaking non-KVM non-PAE kernels (though the risk is very,
very low as there are no known EFER.NX errata), and also eliminates an
easy-to-use mechanism for stressing KVM's handling of guest vs. host EFER
across nested virtualization transitions.
Linus Torvalds [Fri, 13 Aug 2021 02:24:03 +0000 (16:24 -1000)]
Merge tag 'net-5.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Networking fixes, including fixes from netfilter, bpf, can and
ieee802154.
The size of this is pretty normal, but we got more fixes for 5.14
changes this week than last week. Nothing major but the trend is the
opposite of what we like. We'll see how the next week goes..
Current release - regressions:
- r8169: fix ASPM-related link-up regressions
- bridge: fix flags interpretation for extern learn fdb entries
- phy: micrel: fix link detection on ksz87xx switch
- Revert "tipc: Return the correct errno code"
- ptp: fix possible memory leak caused by invalid cast
Current release - new code bugs:
- bpf: add missing bpf_read_[un]lock_trace() for syscall program
- bpf: fix potentially incorrect results with bpf_get_local_storage()
- page_pool: mask the page->signature before the checking, avoid dma
mapping leaks
- netfilter: nfnetlink_hook: 5 fixes to information in netlink dumps
- bnxt_en: fix firmware interface issues with PTP
- mlx5: Bridge, fix ageing time
Previous releases - regressions:
- linkwatch: fix failure to restore device state across
suspend/resume
- bareudp: fix invalid read beyond skb's linear data
Previous releases - always broken:
- bpf: fix integer overflow involving bucket_size
- ppp: fix issues when desired interface name is specified via
netlink
- wwan: mhi_wwan_ctrl: fix possible deadlock
- dsa: microchip: ksz8795: fix number of VLAN related bugs
- dsa: drivers: fix broken backpressure in .port_fdb_dump
- dsa: qca: ar9331: make proper initial port defaults
Misc:
- bpf: add lockdown check for probe_write_user helper
- netfilter: conntrack: remove offload_pickup sysctl before 5.14 is
out
- netfilter: conntrack: collect all entries in one cycle,
heuristically slow down garbage collection scans on idle systems to
prevent frequent wake ups"
* tag 'net-5.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (87 commits)
vsock/virtio: avoid potential deadlock when vsock device remove
wwan: core: Avoid returning NULL from wwan_create_dev()
net: dsa: sja1105: unregister the MDIO buses during teardown
Revert "tipc: Return the correct errno code"
net: mscc: Fix non-GPL export of regmap APIs
net: igmp: increase size of mr_ifc_count
MAINTAINERS: switch to my OMP email for Renesas Ethernet drivers
tcp_bbr: fix u32 wrap bug in round logic if bbr_init() called after 2B packets
net: pcs: xpcs: fix error handling on failed to allocate memory
net: linkwatch: fix failure to restore device state across suspend/resume
net: bridge: fix memleak in br_add_if()
net: switchdev: zero-initialize struct switchdev_notifier_fdb_info emitted by drivers towards the bridge
net: bridge: fix flags interpretation for extern learn fdb entries
net: dsa: sja1105: fix broken backpressure in .port_fdb_dump
net: dsa: lantiq: fix broken backpressure in .port_fdb_dump
net: dsa: lan9303: fix broken backpressure in .port_fdb_dump
net: dsa: hellcreek: fix broken backpressure in .port_fdb_dump
bpf, core: Fix kernel-doc notation
net: igmp: fix data-race in igmp_ifc_timer_expire()
net: Fix memory leak in ieee802154_raw_deliver
...
Linus Torvalds [Fri, 13 Aug 2021 02:16:01 +0000 (16:16 -1000)]
Merge tag 'ceph-for-5.14-rc6' of git://github.com/ceph/ceph-client
Pull ceph fixes from Ilya Dryomov:
"A patch to avoid a soft lockup in ceph_check_delayed_caps() from Luis
and a reference handling fix from Jeff that should address some memory
corruption reports in the snaprealm area.
Both marked for stable"
* tag 'ceph-for-5.14-rc6' of git://github.com/ceph/ceph-client:
ceph: take snap_empty_lock atomically with snaprealm refcount change
ceph: reduce contention in ceph_check_delayed_caps()
i915:
- GVT fix for Windows VM hang.
- Display fix of 12 BPC bits for display 12 and newer.
- Don't try to access some media register for fused off domains.
- Fix kerneldoc build warnings.
* tag 'drm-fixes-2021-08-13' of git://anongit.freedesktop.org/drm/drm:
drm/doc/rfc: drop lmem uapi section
drm/i915: Only access SFC_DONE when media domain is not fused off
drm/i915/display: Fix the 12 BPC bits for PIPE_MISC reg
drm/amd/display: use GFP_ATOMIC in amdgpu_dm_irq_schedule_work
drm/amd/display: Remove invalid assert for ODM + MPC case
drm/amd/pm: bug fix for the runtime pm BACO
drm/amdgpu: handle VCN instances when harvesting (v2)
drm/meson: fix colour distortion from HDR set during vendor u-boot
drm/i915/gvt: Fix cached atomics setting for Windows VM
drm/amdgpu: Add preferred mode in modeset when freesync video mode's enabled.
drm/amd/pm: Fix a memory leak in an error handling path in 'vangogh_tables_init()'
drm/amdgpu: don't enable baco on boco platforms in runpm
drm/amdgpu: set RAS EEPROM address from VBIOS
drm/amd/pm: update smu v13.0.1 firmware header
drm/mediatek: Fix cursor plane no update
drm/mediatek: mtk-dpi: Set out_fmt from config if not the last bridge
drm/mediatek: dpi: Fix NULL dereference in mtk_dpi_bridge_atomic_check
When both the old and the new PCI drivers are enabled
in the same kernel, there are a couple of namespace
conflicts that cause a build failure:
drivers/pci/controller/pci-ixp4xx.c:38: error: "IXP4XX_PCI_CSR" redefined [-Werror]
38 | #define IXP4XX_PCI_CSR 0x1c
|
In file included from arch/arm/mach-ixp4xx/include/mach/hardware.h:23,
from arch/arm/mach-ixp4xx/include/mach/io.h:15,
from arch/arm/include/asm/io.h:198,
from include/linux/io.h:13,
from drivers/pci/controller/pci-ixp4xx.c:20:
arch/arm/mach-ixp4xx/include/mach/ixp4xx-regs.h:221: note: this is the location of the previous definition
221 | #define IXP4XX_PCI_CSR(x) ((volatile u32 *)(IXP4XX_PCI_CFG_BASE_VIRT+(x)))
|
drivers/pci/controller/pci-ixp4xx.c:148:12: error: 'ixp4xx_pci_read' redeclared as different kind of symbol
148 | static int ixp4xx_pci_read(struct ixp4xx_pci *p, u32 addr, u32 cmd, u32 *data)
| ^~~~~~~~~~~~~~~
Rename both the ixp4xx_pci_read/ixp4xx_pci_write functions and the
IXP4XX_PCI_CSR macro. In each case, I went with the version that
has fewer callers to keep the change small.
Linus Walleij [Sat, 7 Aug 2021 22:55:18 +0000 (00:55 +0200)]
ARM: configs: Update the nhk8815_defconfig
The platform lost the framebuffer due to a commit solving a
circular dependency in v5.14-rc1, so add it back in by explicitly
selecting the framebuffer.
Also fix up some Kconfig options that got dropped or moved around
while we're at it.
Dave Airlie [Thu, 12 Aug 2021 20:29:12 +0000 (06:29 +1000)]
Merge tag 'drm-intel-fixes-2021-08-12' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes
- GVT fix for Windows VM hang.
- Display fix of 12 BPC bits for display 12 and newer.
- Don't try to access some media register for fused off domains.
- Fix kerneldoc build warnings.
Jakub Kicinski [Thu, 12 Aug 2021 18:50:16 +0000 (11:50 -0700)]
Merge tag 'ieee802154-for-davem-2021-08-12' of git://git.kernel.org/pub/scm/linux/kernel/git/sschmidt/wpan
Stefan Schmidt says:
====================
ieee802154 for net 2021-08-12
Mostly fixes coming from bot reports. Dongliang Mu tackled some syzkaller
reports in hwsim again and Takeshi Misawa a memory leak in ieee802154 raw.
* tag 'ieee802154-for-davem-2021-08-12' of git://git.kernel.org/pub/scm/linux/kernel/git/sschmidt/wpan:
net: Fix memory leak in ieee802154_raw_deliver
ieee802154: hwsim: fix GPF in hwsim_new_edge_nl
ieee802154: hwsim: fix GPF in hwsim_set_edge_lqi
====================
Babu Moger [Mon, 2 Aug 2021 19:38:58 +0000 (14:38 -0500)]
x86/resctrl: Fix default monitoring groups reporting
Creating a new sub monitoring group in the root /sys/fs/resctrl leads to
getting the "Unavailable" value for mbm_total_bytes and mbm_local_bytes
on the entire filesystem.
When a new monitoring group is created, a new RMID is assigned to the
new group. But the RMID is not active yet. When the events are read on
the new RMID, it is expected to report the status as "Unavailable".
When the user reads the events on the default monitoring group with
multiple subgroups, the events on all subgroups are consolidated
together. Currently, if any of the RMID reads report as "Unavailable",
then everything will be reported as "Unavailable".
Fix the issue by discarding the "Unavailable" reads and reporting all
the successful RMID reads. This is not a problem on Intel systems as
Intel reports 0 on Inactive RMIDs.
lock_sock() may do initiative schedule when the 'sk' is owned by
other thread at the same time, we would receivce a warning message
that "scheduling while atomic".
Even worse, if the next task (selected by the scheduler) try to
release a 'sk', it need to request vsock_table_lock and the deadlock
occur, cause the system into softlockup state.
Call trace:
queued_spin_lock_slowpath
vsock_remove_bound
vsock_remove_sock
virtio_transport_release
__vsock_release
vsock_release
__sock_release
sock_close
__fput
____fput
So we should not require sk_lock in this case, just like the behavior
in vhost_vsock or vmci.
The problem was the "trace(read_max,count)" where the "count" should be
"$count" as "onmax()" only handles variables (although it really should be
able to figure out that "count" is a field of sys_enter_read). But there's
a path that does not find the variable and ends up passing a NULL for the
event, which ends up getting passed to "strcmp()".
Add a check for NULL to return and error on the command with:
init: Suppress wrong warning for bootconfig cmdline parameter
Since the 'bootconfig' command line parameter is handled before
parsing the command line, it doesn't use early_param(). But in
this case, kernel shows a wrong warning message about it.
Commit 2860cd8a2353 ("livepatch: Use the default ftrace_ops instead of
REGS when ARGS is available") intends to enable config LIVEPATCH when
ftrace with ARGS is available. However, the chain of configs to enable
LIVEPATCH is incomplete, as HAVE_DYNAMIC_FTRACE_WITH_ARGS is available,
but the definition of DYNAMIC_FTRACE_WITH_ARGS, combining DYNAMIC_FTRACE
and HAVE_DYNAMIC_FTRACE_WITH_ARGS, needed to enable LIVEPATCH, is missing
in the commit.
Fortunately, ./scripts/checkkconfigsymbols.py detects this and warns:
So, define the config DYNAMIC_FTRACE_WITH_ARGS analogously to the already
existing similar configs, DYNAMIC_FTRACE_WITH_REGS and
DYNAMIC_FTRACE_WITH_DIRECT_CALLS, in ./kernel/trace/Kconfig to connect the
chain of configs.
trace/timerlat: Add a header with PREEMPT_RT additional fields
Some extra flags are printed to the trace header when using the
PREEMPT_RT config. The extra flags are: need-resched-lazy,
preempt-lazy-depth, and migrate-disable.
Without printing these fields, the timerlat specific fields are
shifted by three positions, for example:
trace/osnoise: Add a header with PREEMPT_RT additional fields
Some extra flags are printed to the trace header when using the
PREEMPT_RT config. The extra flags are: need-resched-lazy,
preempt-lazy-depth, and migrate-disable.
Without printing these fields, the osnoise specific fields are
shifted by three positions, for example:
Linus Torvalds [Thu, 12 Aug 2021 17:20:16 +0000 (07:20 -1000)]
Merge branch 'for-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull ucounts fix from Eric Biederman:
"This fixes the ucount sysctls on big endian architectures.
The counts were expanded to be longs instead of ints, and the sysctl
code was overlooked, so only the low 32bit were being processed. On
litte endian just processing the low 32bits is fine, but on 64bit big
endian processing just the low 32bits results in the high order bits
instead of the low order bits being processed and nothing works
proper.
This change took a little bit to mature as we have the SYSCTL_ZERO,
and SYSCTL_INT_MAX macros that are only usable for sysctls operating
on ints, but unfortunately are not obviously broken. Which resulted in
the versions of this change working on big endian and not on little
endian, because the int SYSCTL_ZERO when extended 64bit wound up being
0x100000000. So we only allowed values greater than 0x100000000 and
less than 0faff. Which unfortunately broken everything that tried to
set the sysctls. (First reported with the windows subsystem for
linux).
I have tested this on x86_64 64bit after first reproducing the
problems with the earlier version of this change, and then verifying
the problems do not exist when we use appropriate long min and max
values for extra1 and extra2"
* 'for-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
ucounts: add missing data type changes
Andy Shevchenko [Wed, 11 Aug 2021 12:48:45 +0000 (15:48 +0300)]
wwan: core: Avoid returning NULL from wwan_create_dev()
Make wwan_create_dev() to return either valid or error pointer,
In some cases it may return NULL. Prevent this by converting
it to the respective error pointer.
cifs: Call close synchronously during unlink/rename/lease break.
During unlink/rename/lease break, deferred work for close is
scheduled immediately but in an asynchronous manner which might
lead to race with actual(unlink/rename) commands.
This change will schedule close synchronously which will avoid
the race conditions with other commands.
Maximilian Heyne [Thu, 12 Aug 2021 13:09:27 +0000 (13:09 +0000)]
xen/events: Fix race in set_evtchn_to_irq
There is a TOCTOU issue in set_evtchn_to_irq. Rows in the evtchn_to_irq
mapping are lazily allocated in this function. The check whether the row
is already present and the row initialization is not synchronized. Two
threads can at the same time allocate a new row for evtchn_to_irq and
add the irq mapping to the their newly allocated row. One thread will
overwrite what the other has set for evtchn_to_irq[row] and therefore
the irq mapping is lost. This will trigger a BUG_ON later in
bind_evtchn_to_cpu:
This patch sets evtchn_to_irq rows via a cmpxchg operation so that they
will be set only once. The row is now cleared before writing it to
evtchn_to_irq in order to not create a race once the row is visible for
other threads.
While at it, do not require the page to be zeroed, because it will be
overwritten with -1's in clear_evtchn_to_irq_row anyway.
Hans de Goede [Thu, 12 Aug 2021 14:55:13 +0000 (16:55 +0200)]
platform/x86: asus-nb-wmi: Add tablet_mode_sw=lid-flip quirk for the TP200s
The Asus TP200s / E205SA 360 degree hinges 2-in-1 supports reporting
SW_TABLET_MODE info through the ASUS_WMI_DEVID_LID_FLIP WMI device-id.
Add a quirk to enable this.
Hans de Goede [Thu, 12 Aug 2021 14:55:12 +0000 (16:55 +0200)]
platform/x86: asus-nb-wmi: Allow configuring SW_TABLET_MODE method with a module option
Unfortunately we have been unable to find a reliable way to detect if
and how SW_TABLET_MODE reporting is supported, so we are relying on
DMI quirks for this.
Add a module-option to specify the SW_TABLET_MODE method so that this can
be easily tested without needing to rebuild the kernel.
riscv: Fix comment regarding kernel mapping overlapping with IS_ERR_VALUE
The current comment states that we check if the 64-bit kernel mapping
overlaps with the last 4K of the address space that is reserved to
error values in create_kernel_page_table, which is not the case since it
is done in setup_vm. But anyway, remove the reference to any function
and simply note that in 64-bit kernel, the check should be done as soon
as the kernel mapping base address is known.
Fixes: db6b84a368b4 ("riscv: Make sure the kernel mapping does not overlap with IS_ERR_VALUE") Signed-off-by: Alexandre Ghiti <[email protected]> Cc: [email protected] Signed-off-by: Palmer Dabbelt <[email protected]>
Changbin Du [Thu, 22 Jul 2021 02:17:15 +0000 (10:17 +0800)]
riscv: kexec: do not add '-mno-relax' flag if compiler doesn't support it
The RISC-V special option '-mno-relax' which to disable linker relaxations
is supported by GCC8+. For GCC7 and lower versions do not support this
option.
powerpc/xive: Do not skip CPU-less nodes when creating the IPIs
On PowerVM, CPU-less nodes can be populated with hot-plugged CPUs at
runtime. Today, the IPI is not created for such nodes, and hot-plugged
CPUs use a bogus IPI, which leads to soft lockups.
We can not directly allocate and request the IPI on demand because
bringup_up() is called under the IRQ sparse lock. The alternative is
to allocate the IPIs for all possible nodes at startup and to request
the mapping on demand when the first CPU of a node is brought up.
Christophe Leroy [Tue, 10 Aug 2021 16:13:17 +0000 (16:13 +0000)]
powerpc/interrupt: Do not call single_step_exception() from other exceptions
single_step_exception() is called by emulate_single_step() which
is called from (at least) alignment exception() handler and
program_check_exception() handler.
Redefine it as a regular __single_step_exception() which is called
by both single_step_exception() handler and emulate_single_step()
function.
Here the problem is that by re-enterring an exception handler,
kuap_save_and_lock() is called a second time with this time KUAP
access locked, leading to regs->kuap being overwritten hence
KUAP not being unlocked at exception exit as expected.
Do not call do_IRQ() from timer_interrupt() directly. Instead,
redefine do_IRQ() as a standard function named __do_IRQ(), and
call it from both do_IRQ() and time_interrupt() handlers.
Takashi Sakamoto [Thu, 12 Aug 2021 02:28:39 +0000 (11:28 +0900)]
ALSA: oxfw: fix functioal regression for silence in Apogee Duet FireWire
OXFW 971 has no function to use the value in syt field of received
isochronous packet for playback timing generation. In kernel prepatch for
v5.14, ALSA OXFW driver got change to send NO_INFO value in the field
instead of actual timing value. The change brings Apogee Duet FireWire to
generate no playback sound, while output meter moves.
As long as I investigate, _any_ value in the syt field takes the device to
generate sound. It's reasonable to think that the device just ignores data
blocks in packet with NO_INFO value in its syt field for audio data
processing.
This commit adds a new flag for the quirk to fix regression.
Jaroslav Kysela [Wed, 11 Aug 2021 16:14:41 +0000 (18:14 +0200)]
ALSA: hda - fix the 'Capture Switch' value change notifications
The original code in the cap_put_caller() function does not
handle correctly the positive values returned from the passed
function for multiple iterations. It means that the change
notifications may be lost.
Daniel Vetter [Tue, 10 Aug 2021 14:27:48 +0000 (16:27 +0200)]
drm/doc/rfc: drop lmem uapi section
We still have quite a bit more work to do with overall reworking of
the ttm-based dg1 code, but the uapi stuff is now finalized with the
latest pull. So remove that.
This also fixes kerneldoc build warnings because we've included the
same headers in two places, resulting in sphinx complaining about
duplicated symbols. This regression has been created when we moved the
uapi definitions to the real include/uapi/ folder in 727ecd99a4c9
("drm/doc/rfc: drop the i915_gem_lmem.h header")
v2: Fix a few references that I missed, the htmldocs build took
forever.
Matt Roper [Fri, 6 Aug 2021 17:41:30 +0000 (10:41 -0700)]
drm/i915: Only access SFC_DONE when media domain is not fused off
The SFC_DONE register lives within the corresponding VD0/VD2/VD4/VD6
forcewake domain and is not accessible if the vdbox in that domain is
fused off and the forcewake is not initialized.
This mistake went unnoticed because until recently we were using the
wrong register offset for the SFC_DONE register; once the register
offset was corrected, we started hitting errors like
Ankit Nautiyal [Wed, 11 Aug 2021 05:18:57 +0000 (10:48 +0530)]
drm/i915/display: Fix the 12 BPC bits for PIPE_MISC reg
Till DISPLAY12 the PIPE_MISC bits 5-7 are used to set the
Dithering BPC, with valid values of 6, 8, 10 BPC.
For ADLP+ these bits are used to set the PORT OUTPUT BPC, with valid
values of: 6, 8, 10, 12 BPC, and need to be programmed whether
dithering is enabled or not.
This patch:
-corrects the bits 5-7 for PIPE MISC register for 12 BPC.
-renames the bits and mask to have generic names for these bits for
dithering bpc and port output bpc.
v3: Added a note for MIPI DSI which uses the PIPE_MISC for readout
for pipe_bpp. (Uma Shankar)
v2: Added 'display' to the subject and fixes tag. (Uma Shankar)
Vladimir Oltean [Wed, 11 Aug 2021 11:59:45 +0000 (14:59 +0300)]
net: dsa: sja1105: unregister the MDIO buses during teardown
The call to sja1105_mdiobus_unregister is present in the error path but
absent from the main driver unbind path.
Fixes: 5a8f09748ee7 ("net: dsa: sja1105: register the MDIO buses for 100base-T1 and 100base-TX") Signed-off-by: Vladimir Oltean <[email protected]> Reviewed-by: Florian Fainelli <[email protected]> Signed-off-by: David S. Miller <[email protected]>
Hoang Le [Wed, 11 Aug 2021 01:22:09 +0000 (08:22 +0700)]
Revert "tipc: Return the correct errno code"
This reverts commit 0efea3c649f0 because of:
- The returning -ENOBUF error is fine on socket buffer allocation.
- There is side effect in the calling path
tipc_node_xmit()->tipc_link_xmit() when checking error code returning.
Mark Brown [Tue, 10 Aug 2021 12:37:48 +0000 (13:37 +0100)]
net: mscc: Fix non-GPL export of regmap APIs
The ocelot driver makes use of regmap, wrapping it with driver specific
operations that are thin wrappers around the core regmap APIs. These are
exported with EXPORT_SYMBOL, dropping the _GPL from the core regmap
exports which is frowned upon. Add _GPL suffixes to at least the APIs that
are doing register I/O.
Georgi Djakov [Thu, 12 Aug 2021 06:24:39 +0000 (09:24 +0300)]
Revert "interconnect: qcom: icc-rpmh: Add BCMs to commit list in pre_aggregate"
This reverts commit f84f5b6f72e68bbaeb850b58ac167e4a3a47532a, which is
causing regressions on some platforms, preventing them to boot or do a
clean reboot. This is because the above commit is sending also all the
zero bandwidth requests to turn off any resources that might be enabled
unnecessarily, but currently this may turn off interconnects that are
enabled by default, but with no consumer to keep them on.
Let's revert this for now as some platforms are not ready for such
change yet. In the future we can introduce some _ignore_unused option
that could keep also the unused resources on platforms that have only
partial interconnect support and also add .shutdown callbacks to deal
with disabling the resources in the right order.
Linus Torvalds [Thu, 12 Aug 2021 05:56:10 +0000 (19:56 -1000)]
Merge tag 'seccomp-v5.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull seccomp fixes from Kees Cook:
- Fix typo in user notification documentation (Rodrigo Campos)
- Fix userspace counter report when using TSYNC (Hsuan-Chi Kuo, Wiktor
Garbacz)
* tag 'seccomp-v5.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
seccomp: Fix setting loaded filter count during TSYNC
Documentation: seccomp: Fix typo in user notification
jason-jh.lin [Tue, 10 Aug 2021 04:01:48 +0000 (12:01 +0800)]
drm/mediatek: Add component_del in OVL and COLOR remove function
Add component_del in OVL and COLOR remove function.
Fixes: ff1395609e20 ("drm/mediatek: Move mtk_ddp_comp_init() from sub driver to DRM driver") Signed-off-by: jason-jh.lin <[email protected]> Signed-off-by: Chun-Kuang Hu <[email protected]>
Sergey Shtylyov [Tue, 10 Aug 2021 20:17:12 +0000 (23:17 +0300)]
MAINTAINERS: switch to my OMP email for Renesas Ethernet drivers
I'm still going to continue looking after the Renesas Ethernet drivers and
device tree bindings. Now my new employer, Open Mobile Platform (OMP), will
pay for all my upstream work. Let's switch to my OMP email for the reviews.
Neal Cardwell [Wed, 11 Aug 2021 02:40:56 +0000 (22:40 -0400)]
tcp_bbr: fix u32 wrap bug in round logic if bbr_init() called after 2B packets
Currently if BBR congestion control is initialized after more than 2B
packets have been delivered, depending on the phase of the
tp->delivered counter the tracking of BBR round trips can get stuck.
The bug arises because if tp->delivered is between 2^31 and 2^32 at
the time the BBR congestion control module is initialized, then the
initialization of bbr->next_rtt_delivered to 0 will cause the logic to
believe that the end of the round trip is still billions of packets in
the future. More specifically, the following check will fail
repeatedly:
and thus the connection will take up to 2B packets delivered before
that check will pass and the connection will set:
bbr->round_start = 1;
This could cause many mechanisms in BBR to fail to trigger, for
example bbr_check_full_bw_reached() would likely never exit STARTUP.
This bug is 5 years old and has not been observed, and as a practical
matter this would likely rarely trigger, since it would require
transferring at least 2B packets, or likely more than 3 terabytes of
data, before switching congestion control algorithms to BBR.
This patch is a stable candidate for kernels as far back as v4.9,
when tcp_bbr.c was added.
Wong Vee Khee [Tue, 10 Aug 2021 08:58:12 +0000 (16:58 +0800)]
net: pcs: xpcs: fix error handling on failed to allocate memory
Drivers such as sja1105 and stmmac that call xpcs_create() expects an
error returned by the pcs-xpcs module, but this was not the case on
failed to allocate memory.
Fixed this by returning an -ENOMEM instead of a NULL pointer.
Willy Tarreau [Mon, 9 Aug 2021 16:06:28 +0000 (18:06 +0200)]
net: linkwatch: fix failure to restore device state across suspend/resume
After migrating my laptop from 4.19-LTS to 5.4-LTS a while ago I noticed
that my Ethernet port to which a bond and a VLAN interface are attached
appeared to remain up after resuming from suspend with the cable unplugged
(and that problem still persists with 5.10-LTS).
It happens that the following happens:
- the network driver (e1000e here) prepares to suspend, calls e1000e_down()
which calls netif_carrier_off() to signal that the link is going down.
- netif_carrier_off() adds a link_watch event to the list of events for
this device
- the device is completely stopped.
- the machine suspends
- the cable is unplugged and the machine brought to another location
- the machine is resumed
- the queued linkwatch events are processed for the device
- the device doesn't yet have the __LINK_STATE_PRESENT bit and its events
are silently dropped
- the device is resumed with its link down
- the upper VLAN and bond interfaces are never notified that the link had
been turned down and remain up
- the only way to provoke a change is to physically connect the machine
to a port and possibly unplug it.
The state after resume looks like this:
$ ip -br li | egrep 'bond|eth'
bond0 UP e8:6a:64:64:64:64 <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP>
eth0 DOWN e8:6a:64:64:64:64 <NO-CARRIER,BROADCAST,MULTICAST,SLAVE,UP>
eth0.2@eth0 UP e8:6a:64:64:64:64 <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP>
Placing an explicit call to netdev_state_change() either in the suspend
or the resume code in the NIC driver worked around this but the solution
is not satisfying.
The issue in fact really is in link_watch that loses events while it
ought not to. It happens that the test for the device being present was
added by commit 124eee3f6955 ("net: linkwatch: add check for netdevice
being present to linkwatch_do_dev") in 4.20 to avoid an access to
devices that are not present.
Instead of dropping events, this patch proceeds slightly differently by
postponing their handling so that they happen after the device is fully
resumed.
Elliot Berman [Wed, 11 Aug 2021 15:59:14 +0000 (08:59 -0700)]
cfi: Use rcu_read_{un}lock_sched_notrace
If rcu_read_lock_sched tracing is enabled, the tracing subsystem can
perform a jump which needs to be checked by CFI. For example, stm_ftrace
source is enabled as a module and hooks into enabled ftrace events. This
can cause an recursive loop where find_shadow_check_fn ->
rcu_read_lock_sched -> (call to stm_ftrace generates cfi slowpath) ->
find_shadow_check_fn -> rcu_read_lock_sched -> ...
To avoid the recursion, either the ftrace codes needs to be marked with
__no_cfi or CFI should not trace. Use the "_notrace" in CFI to avoid
tracing so that CFI can guard ftrace.
Tejun Heo [Wed, 11 Aug 2021 17:41:45 +0000 (07:41 -1000)]
Revert "block/mq-deadline: Add cgroup support"
This reverts commit 08a9ad8bf607 ("block/mq-deadline: Add cgroup support")
and a follow-up commit c06bc5a3fb42 ("block/mq-deadline: Remove a
WARN_ON_ONCE() call"). The added cgroup support has the following issues:
* It breaks cgroup interface file format rule by adding custom elements to a
nested key-value file.
* It registers mq-deadline as a cgroup-aware policy even though all it's
doing is collecting per-cgroup stats. Even if we need these stats, this
isn't the right way to add them.
A recent change in LLVM causes module_{c,d}tor sections to appear when
CONFIG_K{A,C}SAN are enabled, which results in orphan section warnings
because these are not handled anywhere:
ld.lld: warning: arch/x86/pci/built-in.a(legacy.o):(.text.asan.module_ctor) is being placed in '.text.asan.module_ctor'
ld.lld: warning: arch/x86/pci/built-in.a(legacy.o):(.text.asan.module_dtor) is being placed in '.text.asan.module_dtor'
ld.lld: warning: arch/x86/pci/built-in.a(legacy.o):(.text.tsan.module_ctor) is being placed in '.text.tsan.module_ctor'
Fangrui explains: "the function asan.module_ctor has the SHF_GNU_RETAIN
flag, so it is in a separate section even with -fno-function-sections
(default)".
Place them in the TEXT_TEXT section so that these technologies continue
to work with the newer compiler versions. All of the KASAN and KCSAN
KUnit tests continue to pass after this change.
tools/testing/nvdimm/test/nfit.c: In function ‘nd_intel_test_finish_query’:
tools/testing/nvdimm/test/nfit.c:436:37: warning: this statement may
fall through [-Wimplicit-fallthrough=]
436 | fw->missed_activate = false;
| ~~~~~~~~~~~~~~~~~~~~^~~~~~~
tools/testing/nvdimm/test/nfit.c:438:9: note: here
438 | case FW_STATE_UPDATED:
| ^~~~
Dan Williams [Fri, 30 Jul 2021 16:46:04 +0000 (09:46 -0700)]
libnvdimm/region: Fix label activation vs errors
There are a few scenarios where init_active_labels() can return without
registering deactivate_labels() to run when the region is disabled. In
particular label error injection creates scenarios where a DIMM is
disabled, but labels on other DIMMs in the region become activated.
Arrange for init_active_labels() to always register deactivate_labels().
Dan Williams [Wed, 11 Aug 2021 18:53:37 +0000 (11:53 -0700)]
ACPI: NFIT: Fix support for virtual SPA ranges
Fix the NFIT parsing code to treat a 0 index in a SPA Range Structure as
a special case and not match Region Mapping Structures that use 0 to
indicate that they are not mapped. Without this fix some platform BIOS
descriptions of "virtual disk" ranges do not result in the pmem driver
attaching to the range.
Details:
In addition to typical persistent memory ranges, the ACPI NFIT may also
convey "virtual" ranges. These ranges are indicated by a UUID in the SPA
Range Structure of UUID_VOLATILE_VIRTUAL_DISK, UUID_VOLATILE_VIRTUAL_CD,
UUID_PERSISTENT_VIRTUAL_DISK, or UUID_PERSISTENT_VIRTUAL_CD. The
critical difference between virtual ranges and UUID_PERSISTENT_MEMORY,
is that virtual do not support associations with Region Mapping
Structures. For this reason the "index" value of virtual SPA Range
Structures is allowed to be 0. If a platform BIOS decides to represent
NVDIMMs with disconnected "Region Mapping Structures" (range-index ==
0), the kernel may falsely associate them with standalone ranges where
the "SPA Range Structure Index" is also zero. When this happens the
driver may falsely require labels where "virtual disks" are expected to
be label-less. I.e. "label-less" is where the namespace-range ==
region-range and the pmem driver attaches with no user action to create
a namespace.
Hsuan-Chi Kuo [Thu, 4 Mar 2021 23:37:08 +0000 (17:37 -0600)]
seccomp: Fix setting loaded filter count during TSYNC
The desired behavior is to set the caller's filter count to thread's.
This value is reported via /proc, so this fixes the inaccurate count
exposed to userspace; it is not used for reference counting, etc.
Yonghong Song [Tue, 10 Aug 2021 23:05:37 +0000 (16:05 -0700)]
bpf: Add rcu_read_lock in bpf_get_current_[ancestor_]cgroup_id() helpers
Currently, if bpf_get_current_cgroup_id() or
bpf_get_current_ancestor_cgroup_id() helper is
called with sleepable programs e.g., sleepable
fentry/fmod_ret/fexit/lsm programs, a rcu warning
may appear. For example, if I added the following
hack to test_progs/test_lsm sleepable fentry program
test_sys_setdomainname:
--- a/tools/testing/selftests/bpf/progs/lsm.c
+++ b/tools/testing/selftests/bpf/progs/lsm.c
@@ -168,6 +168,10 @@ int BPF_PROG(test_sys_setdomainname, struct pt_regs *regs)
int buf = 0;
long ret;
+ __u64 cg_id = bpf_get_current_cgroup_id();
+ if (cg_id == 1000)
+ copy_test++;
+
ret = bpf_copy_from_user(&buf, sizeof(buf), ptr);
if (len == -2 && ret == 0 && buf == 1234)
copy_test++;
I will hit the following rcu warning:
include/linux/cgroup.h:481 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
1 lock held by test_progs/260:
#0: ffffffffa5173360 (rcu_read_lock_trace){....}-{0:0}, at: __bpf_prog_enter_sleepable+0x0/0xa0
stack backtrace:
CPU: 1 PID: 260 Comm: test_progs Tainted: G O 5.14.0-rc2+ #176
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack_lvl+0x56/0x7b
bpf_get_current_cgroup_id+0x9c/0xb1
bpf_prog_a29888d1c6706e09_test_sys_setdomainname+0x3e/0x89c
bpf_trampoline_6442469132_0+0x2d/0x1000
__x64_sys_setdomainname+0x5/0x110
do_syscall_64+0x3a/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae
I can get similar warning using bpf_get_current_ancestor_cgroup_id() helper.
syzbot reported a similar issue in [1] for syscall program. Helper
bpf_get_current_cgroup_id() or bpf_get_current_ancestor_cgroup_id()
has the following callchain:
task_dfl_cgroup
task_css_set
task_css_set_check
and we have
#define task_css_set_check(task, __c) \
rcu_dereference_check((task)->cgroups, \
lockdep_is_held(&cgroup_mutex) || \
lockdep_is_held(&css_set_lock) || \
((task)->flags & PF_EXITING) || (__c))
Since cgroup_mutex/css_set_lock is not held and the task
is not existing and rcu read_lock is not held, a warning
will be issued. Note that bpf sleepable program is protected by
rcu_read_lock_trace().
The above sleepable bpf programs are already protected
by migrate_disable(). Adding rcu_read_lock() in these
two helpers will silence the above warning.
I marked the patch fixing 95b861a7935b
("bpf: Allow bpf_get_current_ancestor_cgroup_id for tracing")
which added bpf_get_current_ancestor_cgroup_id() to tracing programs
in 5.14. I think backporting 5.14 is probably good enough as sleepable
progrems are not widely used.
This patch should fix [1] as well since syscall program is a sleepable
program protected with migrate_disable().
Damien Le Moal [Fri, 6 Aug 2021 00:43:11 +0000 (09:43 +0900)]
pinctrl: k210: Fix k210_fpioa_probe()
In k210_fpioa_probe(), add missing calls to clk_disable_unprepare() in
case of error after cenabling the clk and pclk clocks. Also add missing
error handling when enabling pclk.
Eli Cohen [Wed, 11 Aug 2021 05:37:59 +0000 (08:37 +0300)]
vdpa/mlx5: Fix queue type selection logic
get_queue_type() comments that splict virtqueue is preferred, however,
the actual logic preferred packed virtqueues. Since firmware has not
supported packed virtqueues we ended up using split virtqueues as was
desired.
Since we do not advertise support for packed virtqueues, we add a check
to verify split virtqueues are indeed supported.
Eli Cohen [Wed, 11 Aug 2021 05:37:13 +0000 (08:37 +0300)]
vdpa/mlx5: Avoid destroying MR on empty iotlb
The current code treats an empty iotlb provdied in set_map() as a
special case and destroy the memory region object. This must not be done
since the virtqueue objects reference this MR. Doing so will cause the
driver unload to emit errors and log timeouts caused by the firmware
complaining on busy resources.
This patch treats an empty iotlb as any other change of mapping. In this
case, mlx5_vdpa_create_mr() will fail and the entire set_map() call to
fail.
This issue has not been encountered before but was seen to occur in a
non-official version of qemu. Since qemu is a userspace program, the
driver must protect against such case.
Xie Yongji [Mon, 9 Aug 2021 10:16:09 +0000 (18:16 +0800)]
virtio-blk: Add validation for block size in config space
An untrusted device might presents an invalid block size
in configuration space. This tries to add validation for it
in the validate callback and clear the VIRTIO_BLK_F_BLK_SIZE
feature bit if the value is out of the supported range.
And we also double check the value in virtblk_probe() in
case that it's changed after the validation.
Neeraj Upadhyay [Fri, 25 Jun 2021 03:25:02 +0000 (08:55 +0530)]
vringh: Use wiov->used to check for read/write desc order
As __vringh_iov() traverses a descriptor chain, it populates
each descriptor entry into either read or write vring iov
and increments that iov's ->used member. So, as we iterate
over a descriptor chain, at any point, (riov/wriov)->used
value gives the number of descriptor enteries available,
which are to be read or written by the device. As all read
iovs must precede the write iovs, wiov->used should be zero
when we are traversing a read descriptor. Current code checks
for wiov->i, to figure out whether any previous entry in the
current descriptor chain was a write descriptor. However,
iov->i is only incremented, when these vring iovs are consumed,
at a later point, and remain 0 in __vringh_iov(). So, correct
the check for read and write descriptor order, to use
wiov->used.
Do not call vDPA drivers' callbacks with vq indicies larger than what
the drivers indicate that they support. vDPA drivers do not bounds
check the indices.
vdpa: Add documentation for vdpa_alloc_device() macro
The return value of vdpa_alloc_device() macro is not very
clear, so that most of callers did the wrong check. Let's
add some comments to better document it.
vDPA/ifcvf: Fix return value check for vdpa_alloc_device()
The vdpa_alloc_device() returns an error pointer upon
failure, not NULL. To handle the failure correctly, this
replaces NULL check with IS_ERR() check and propagate the
error upwards.
vp_vdpa: Fix return value check for vdpa_alloc_device()
The vdpa_alloc_device() returns an error pointer upon
failure, not NULL. To handle the failure correctly, this
replaces NULL check with IS_ERR() check and propagate the
error upwards.
vdpa_sim: Fix return value check for vdpa_alloc_device()
The vdpa_alloc_device() returns an error pointer upon
failure, not NULL. To handle the failure correctly, this
replaces NULL check with IS_ERR() check and propagate the
error upwards.
commit a5b8ca97fbf8 ("arm64: do not descend to vdso directories twice")
changes the cleaning behavior of arm64's vdso files, in that vdso.lds,
vdso.so, and vdso.so.dbg are not removed upon a 'make clean/mrproper':
$ make defconfig ARCH=arm64
$ make ARCH=arm64
$ make mrproper ARCH=arm64
$ git clean -nxdf
Would remove arch/arm64/kernel/vdso/vdso.lds
Would remove arch/arm64/kernel/vdso/vdso.so
Would remove arch/arm64/kernel/vdso/vdso.so.dbg
To remedy this, manually descend into arch/arm64/kernel/vdso upon
cleaning.
After this commit:
$ make defconfig ARCH=arm64
$ make ARCH=arm64
$ make mrproper ARCH=arm64
$ git clean -nxdf
<empty>
Similar results are obtained for the vdso32 equivalent.
Tony Lindgren [Wed, 11 Aug 2021 05:34:46 +0000 (08:34 +0300)]
bus: ti-sysc: Fix error handling for sysc_check_active_timer()
We have changed the return type for sysc_check_active_timer() from -EBUSY
to -ENXIO, but the gpt12 system timer fix still checks for -EBUSY. We are
also not returning on other errors like we did earlier as noted by
Pavel Machek <[email protected]>.
Commit 3ff340e24c9d ("bus: ti-sysc: Fix gpt12 system timer issue with
reserved status") should have been updated for commit 65fb73676112
("bus: ti-sysc: suppress err msg for timers used as clockevent/source").
Let's fix the issue by checking for -ENXIO and returning on any other
errors as suggested by Pavel Machek <[email protected]>.
Fixes: 3ff340e24c9d ("bus: ti-sysc: Fix gpt12 system timer issue with reserved status")
Depends-on: 65fb73676112 ("bus: ti-sysc: suppress err msg for timers used as clockevent/source") Reported-by: Pavel Machek <[email protected]> Reviewed-by: Pavel Machek (CIP) <[email protected]> Cc: Grygorii Strashko <[email protected]> Cc: Jarkko Nikula <[email protected]> Signed-off-by: Tony Lindgren <[email protected]>
Linus Torvalds [Wed, 11 Aug 2021 02:34:34 +0000 (16:34 -1000)]
Merge tag 'arc-5.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC fixes from Vineet Gupta:
- Fix FPU_STATUS update
- Update my email address
- Other spellos and fixes
* tag 'arc-5.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
MAINTAINERS: update Vineet's email address
ARC: fp: set FPU_STATUS.FWE to enable FPU_STATUS update on context switch
ARC: Fix CONFIG_STACKDEPOT
arc: Fix spelling mistake and grammar in Kconfig
arc: Prefer unsigned int to bare use of unsigned
i2c: dev: zero out array used for i2c reads from userspace
If an i2c driver happens to not provide the full amount of data that a
user asks for, it is possible that some uninitialized data could be sent
to userspace. While all in-kernel drivers look to be safe, just be sure
by initializing the buffer to zero before it is passed to the i2c driver
so that any future drivers will not have this issue.
Also properly copy the amount of data recvieved to the userspace buffer,
as pointed out by Dan Carpenter.
Vladimir Oltean [Tue, 10 Aug 2021 11:50:24 +0000 (14:50 +0300)]
net: switchdev: zero-initialize struct switchdev_notifier_fdb_info emitted by drivers towards the bridge
The blamed commit added a new field to struct switchdev_notifier_fdb_info,
but did not make sure that all call paths set it to something valid.
For example, a switchdev driver may emit a SWITCHDEV_FDB_ADD_TO_BRIDGE
notifier, and since the 'is_local' flag is not set, it contains junk
from the stack, so the bridge might interpret those notifications as
being for local FDB entries when that was not intended.
To avoid that now and in the future, zero-initialize all
switchdev_notifier_fdb_info structures created by drivers such that all
newly added fields to not need to touch drivers again.
net: bridge: fix flags interpretation for extern learn fdb entries
Ignore fdb flags when adding port extern learn entries and always set
BR_FDB_LOCAL flag when adding bridge extern learn entries. This is
closest to the behaviour we had before and avoids breaking any use cases
which were allowed.
This patch fixes iproute2 calls which assume NUD_PERMANENT and were
allowed before, example:
$ bridge fdb add 00:11:22:33:44:55 dev swp1 extern_learn
Extern learn entries are allowed to roam, but do not expire, so static
or dynamic flags make no sense for them.
KVM: VMX: Use current VMCS to query WAITPKG support for MSR emulation
Use the secondary_exec_controls_get() accessor in vmx_has_waitpkg() to
effectively get the controls for the current VMCS, as opposed to using
vmx->secondary_exec_controls, which is the cached value of KVM's desired
controls for vmcs01 and truly not reflective of any particular VMCS.
While the waitpkg control is not dynamic, i.e. vmcs01 will always hold
the same waitpkg configuration as vmx->secondary_exec_controls, the same
does not hold true for vmcs02 if the L1 VMM hides the feature from L2.
If L1 hides the feature _and_ does not intercept MSR_IA32_UMWAIT_CONTROL,
L2 could incorrectly read/write L1's virtual MSR instead of taking a #GP.
Linus Torvalds [Tue, 10 Aug 2021 16:46:33 +0000 (09:46 -0700)]
Merge tag 'platform-drivers-x86-v5.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86
Pull x86 platform driver fixes from Hans de Goede:
"Small set of pdx86 fixes for 5.14"
* tag 'platform-drivers-x86-v5.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86:
platform/x86: pcengines-apuv2: Add missing terminating entries to gpio-lookup tables
platform/x86: Make dual_accel_detect() KIOX010A + KIOX020A detect more robust
platform/x86: Add and use a dual_accel_detect() helper
Linus Torvalds [Tue, 10 Aug 2021 16:40:09 +0000 (09:40 -0700)]
Merge tag 'ovl-fixes-5.14-rc6-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs fixes from Miklos Szeredi:
"Fix several bugs in overlayfs"
* tag 'ovl-fixes-5.14-rc6-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
ovl: prevent private clone if bind mount is not allowed
ovl: fix uninitialized pointer read in ovl_lookup_real_one()
ovl: fix deadlock in splice write
ovl: skip stale entries in merge dir cache iteration
virtio_pci: Support surprise removal of virtio pci device
When a virtio pci device undergo surprise removal (aka async removal in
PCIe spec), mark the device as broken so that any upper layer drivers can
abort any outstanding operation.
When a virtio net pci device undergo surprise removal which is used by a
NetworkManager, a below call trace was observed.
virtio: Improve vq->broken access to avoid any compiler optimization
Currently vq->broken field is read by virtqueue_is_broken() in busy
loop in one context by virtnet_send_command().
vq->broken is set to true in other process context by
virtio_break_device(). Reader and writer are accessing it without any
synchronization. This may lead to a compiler optimization which may
result to optimize reading vq->broken only once.
Hence, force reading vq->broken on each invocation of
virtqueue_is_broken() and also force writing it so that such
update is visible to the readers.
It is a theoretical fix that isn't yet encountered in the field.
Kenneth Feng [Fri, 6 Aug 2021 02:28:04 +0000 (10:28 +0800)]
drm/amd/pm: bug fix for the runtime pm BACO
In some systems only MACO is supported. This is to fix the problem
that runtime pm is enabled but BACO is not supported. MACO will be
handled seperately.
projects / linux.git / log