Commit Graph

1072577 Commits

Author SHA1 Message Date
Vitaly Kuznetsov
aa3b39f38c KVM: SVM: drop unnecessary code in svm_hv_vmcb_dirty_nested_enlightenments()
Commit 3fa5e8fd0a ("KVM: SVM: delay svm_vcpu_init_msrpm after
svm->vmcb is initialized") re-arranged svm_vcpu_init_msrpm() call in
svm_create_vcpu(), thus making the comment about vmcb being NULL
obsolete. Drop it.

While on it, drop superfluous vmcb_is_clean() check: vmcb_mark_dirty()
is a bit flip, an extra check is unlikely to bring any performance gain.
Drop now-unneeded vmcb_is_clean() helper as well.

Fixes: 3fa5e8fd0a ("KVM: SVM: delay svm_vcpu_init_msrpm after svm->vmcb is initialized")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211220152139.418372-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:15:03 -05:00
Vitaly Kuznetsov
38dfa8308c KVM: SVM: hyper-v: Enable Enlightened MSR-Bitmap support for real
Commit c4327f15df ("KVM: SVM: hyper-v: Enlightened MSR-Bitmap support")
introduced enlightened MSR-Bitmap support for KVM-on-Hyper-V but it didn't
actually enable the support. Similar to enlightened NPT TLB flush and
direct TLB flush features, the guest (KVM) has to tell L0 (Hyper-V) that
it's using the feature by setting the appropriate feature fit in VMCB
control area (sw reserved fields).

Fixes: c4327f15df ("KVM: SVM: hyper-v: Enlightened MSR-Bitmap support")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211220152139.418372-3-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:15:02 -05:00
Sean Christopherson
cdf85e0c5d KVM: SVM: Don't kill SEV guest if SMAP erratum triggers in usermode
Inject a #GP instead of synthesizing triple fault to try to avoid killing
the guest if emulation of an SEV guest fails due to encountering the SMAP
erratum.  The injected #GP may still be fatal to the guest, e.g. if the
userspace process is providing critical functionality, but KVM should
make every attempt to keep the guest alive.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Message-Id: <20220120010719.711476-10-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:15:02 -05:00
Sean Christopherson
3280cc22ae KVM: SVM: Don't apply SEV+SMAP workaround on code fetch or PT access
Resume the guest instead of synthesizing a triple fault shutdown if the
instruction bytes buffer is empty due to the #NPF being on the code fetch
itself or on a page table access.  The SMAP errata applies if and only if
the code fetch was successful and ucode's subsequent data read from the
code page encountered a SMAP violation.  In practice, the guest is likely
hosed either way, but crashing the guest on a code fetch to emulated MMIO
is technically wrong according to the behavior described in the APM.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Message-Id: <20220120010719.711476-9-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:15:01 -05:00
Sean Christopherson
04c40f344d KVM: SVM: Inject #UD on attempted emulation for SEV guest w/o insn buffer
Inject #UD if KVM attempts emulation for an SEV guests without an insn
buffer and instruction decoding is required.  The previous behavior of
allowing emulation if there is no insn buffer is undesirable as doing so
means KVM is reading guest private memory and thus decoding cyphertext,
i.e. is emulating garbage.  The check was previously necessary as the
emulation type was not provided, i.e. SVM needed to allow emulation to
handle completion of emulation after exiting to userspace to handle I/O.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Message-Id: <20220120010719.711476-8-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:15:01 -05:00
Sean Christopherson
132627c64d KVM: SVM: WARN if KVM attempts emulation on #UD or #GP for SEV guests
WARN if KVM attempts to emulate in response to #UD or #GP for SEV guests,
i.e. if KVM intercepts #UD or #GP, as emulation on any fault except #NPF
is impossible since KVM cannot read guest private memory to get the code
stream, and the CPU's DecodeAssists feature only provides the instruction
bytes on #NPF.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Message-Id: <20220120010719.711476-7-seanjc@google.com>
[Warn on EMULTYPE_TRAP_UD_FORCED according to Liam Merwick's review. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:15:01 -05:00
Sean Christopherson
4d31d9eff2 KVM: x86: Pass emulation type to can_emulate_instruction()
Pass the emulation type to kvm_x86_ops.can_emulate_insutrction() so that
a future commit can harden KVM's SEV support to WARN on emulation
scenarios that should never happen.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Message-Id: <20220120010719.711476-6-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:15:00 -05:00
Sean Christopherson
c532f2903b KVM: SVM: Explicitly require DECODEASSISTS to enable SEV support
Add a sanity check on DECODEASSIST being support if SEV is supported, as
KVM cannot read guest private memory and thus relies on the CPU to
provide the instruction byte stream on #NPF for emulation.  The intent of
the check is to document the dependency, it should never fail in practice
as producing hardware that supports SEV but not DECODEASSISTS would be
non-sensical.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Message-Id: <20220120010719.711476-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:15:00 -05:00
Sean Christopherson
0b0be065b7 KVM: SVM: Don't intercept #GP for SEV guests
Never intercept #GP for SEV guests as reading SEV guest private memory
will return cyphertext, i.e. emulating on #GP can't work as intended.

Cc: stable@vger.kernel.org
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Message-Id: <20220120010719.711476-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:15:00 -05:00
Sean Christopherson
31c2558569 Revert "KVM: SVM: avoid infinite loop on NPF from bad address"
Revert a completely broken check on an "invalid" RIP in SVM's workaround
for the DecodeAssists SMAP errata.  kvm_vcpu_gfn_to_memslot() obviously
expects a gfn, i.e. operates in the guest physical address space, whereas
RIP is a virtual (not even linear) address.  The "fix" worked for the
problematic KVM selftest because the test identity mapped RIP.

Fully revert the hack instead of trying to translate RIP to a GPA, as the
non-SEV case is now handled earlier, and KVM cannot access guest page
tables to translate RIP.

This reverts commit e72436bc3a.

Fixes: e72436bc3a ("KVM: SVM: avoid infinite loop on NPF from bad address")
Reported-by: Liam Merwick <liam.merwick@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Message-Id: <20220120010719.711476-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:14:59 -05:00
Sean Christopherson
55467fcd55 KVM: SVM: Never reject emulation due to SMAP errata for !SEV guests
Always signal that emulation is possible for !SEV guests regardless of
whether or not the CPU provided a valid instruction byte stream.  KVM can
read all guest state (memory and registers) for !SEV guests, i.e. can
fetch the code stream from memory even if the CPU failed to do so because
of the SMAP errata.

Fixes: 05d5a48635 ("KVM: SVM: Workaround errata#1096 (insn_len maybe zero on SMAP violation)")
Cc: stable@vger.kernel.org
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Message-Id: <20220120010719.711476-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:14:59 -05:00
Denis Valeev
47c28d436f KVM: x86: nSVM: skip eax alignment check for non-SVM instructions
The bug occurs on #GP triggered by VMware backdoor when eax value is
unaligned. eax alignment check should not be applied to non-SVM
instructions because it leads to incorrect omission of the instructions
emulation.
Apply the alignment check only to SVM instructions to fix.

Fixes: d1cba6c922 ("KVM: x86: nSVM: test eax for 4K alignment for GP errata workaround")
Signed-off-by: Denis Valeev <lemniscattaden@gmail.com>
Message-Id: <Yexlhaoe1Fscm59u@q>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:14:59 -05:00
Like Xu
1ffce0924a KVM: x86/cpuid: Exclude unpermitted xfeatures sizes at KVM_GET_SUPPORTED_CPUID
With the help of xstate_get_guest_group_perm(), KVM can exclude unpermitted
xfeatures in cpuid.0xd.0.eax, in which case the corresponding xfeatures
sizes should also be matched to the permitted xfeatures.

To fix this inconsistency, the permitted_xcr0 and permitted_xss are defined
consistently, which implies 'supported' plus certain permissions for this
task, and it also fixes cpuid.0xd.1.ebx and later leaf-by-leaf queries.

Fixes: 445ecdf79b ("kvm: x86: Exclude unpermitted xfeatures at KVM_GET_SUPPORTED_CPUID")
Signed-off-by: Like Xu <likexu@tencent.com>
Message-Id: <20220125115223.33707-1-likexu@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:14:58 -05:00
Wanpeng Li
35fe7cfbab KVM: LAPIC: Also cancel preemption timer during SET_LAPIC
The below warning is splatting during guest reboot.

  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 1931 at arch/x86/kvm/x86.c:10322 kvm_arch_vcpu_ioctl_run+0x874/0x880 [kvm]
  CPU: 0 PID: 1931 Comm: qemu-system-x86 Tainted: G          I       5.17.0-rc1+ #5
  RIP: 0010:kvm_arch_vcpu_ioctl_run+0x874/0x880 [kvm]
  Call Trace:
   <TASK>
   kvm_vcpu_ioctl+0x279/0x710 [kvm]
   __x64_sys_ioctl+0x83/0xb0
   do_syscall_64+0x3b/0xc0
   entry_SYSCALL_64_after_hwframe+0x44/0xae
  RIP: 0033:0x7fd39797350b

This can be triggered by not exposing tsc-deadline mode and doing a reboot in
the guest. The lapic_shutdown() function which is called in sys_reboot path
will not disarm the flying timer, it just masks LVTT. lapic_shutdown() clears
APIC state w/ LVT_MASKED and timer-mode bit is 0, this can trigger timer-mode
switch between tsc-deadline and oneshot/periodic, which can result in preemption
timer be cancelled in apic_update_lvtt(). However, We can't depend on this when
not exposing tsc-deadline mode and oneshot/periodic modes emulated by preemption
timer. Qemu will synchronise states around reset, let's cancel preemption timer
under KVM_SET_LAPIC.

Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1643102220-35667-1-git-send-email-wanpengli@tencent.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:14:58 -05:00
Jim Mattson
519669cc58 KVM: VMX: Remove vmcs_config.order
The maximum size of a VMCS (or VMXON region) is 4096. By definition,
these are order 0 allocations.

Signed-off-by: Jim Mattson <jmattson@google.com>
Message-Id: <20220125004359.147600-1-jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-26 12:14:58 -05:00
Bjorn Helgaas
66d28b21fe PCI/sysfs: Find shadow ROM before static attribute initialization
Ville reported that the sysfs "rom" file for VGA devices disappeared after
527139d738 ("PCI/sysfs: Convert "rom" to static attribute").

Prior to 527139d738, FINAL fixups, including pci_fixup_video() where we
find shadow ROMs, were run before pci_create_sysfs_dev_files() created the
sysfs "rom" file.

After 527139d738, "rom" is a static attribute and is created before FINAL
fixups are run, so we didn't create "rom" files for shadow ROMs:

  acpi_pci_root_add
    ...
      pci_scan_single_device
        pci_device_add
          pci_fixup_video                    # <-- new HEADER fixup
          device_add
            ...
              if (grp->is_visible())
                pci_dev_rom_attr_is_visible  # after 527139d738
    pci_bus_add_devices
      pci_bus_add_device
        pci_fixup_device(pci_fixup_final)
          pci_fixup_video                    # <-- previous FINAL fixup
        pci_create_sysfs_dev_files
          if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
            sysfs_create_bin_file("rom")     # before 527139d738

Change pci_fixup_video() to be a HEADER fixup so it runs before sysfs
static attributes are initialized.

Rename the Loongson pci_fixup_radeon() to pci_fixup_video() and make its
dmesg logging identical to the others since it is doing the same job.

Link: https://lore.kernel.org/r/YbxqIyrkv3GhZVxx@intel.com
Fixes: 527139d738 ("PCI/sysfs: Convert "rom" to static attribute")
Link: https://lore.kernel.org/r/20220126154001.16895-1-helgaas@kernel.org
Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org			# v5.13+
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Krzysztof Wilczyński <kw@linux.com>
2022-01-26 10:41:21 -06:00
David S. Miller
2f65132843 Merge branch 'lan966x-fixes'
Horatiu Vultur says:

====================
net: lan966x: Fixes for sleep in atomic context

This patch series contains 2 fixes for lan966x that is sleeping in atomic
context. The first patch fixes the injection of the frames while the second
one fixes the updating of the MAC table.

v1->v2:
 - correct the fix tag in the second patch, it was using the wrong sha.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-26 15:45:49 +00:00
Horatiu Vultur
77bdaf39f3 net: lan966x: Fix sleep in atomic context when updating MAC table
The function lan966x_mac_wait_for_completion is used to poll the status
of the MAC table using the function readx_poll_timeout. The problem with
this function is that is called also from atomic context. Therefore
update the function to use readx_poll_timeout_atomic.

Fixes: e18aba8941 ("net: lan966x: add mactable support")
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-26 15:45:49 +00:00
Horatiu Vultur
b6ab149654 net: lan966x: Fix sleep in atomic context when injecting frames
On lan966x, when injecting a frame it was polling the register
QS_INJ_STATUS to see if it can continue with the injection of the frame.
The problem was that it was using readx_poll_timeout which could sleep
in atomic context.
This patch fixes this issue by using readx_poll_timeout_atomic.

Fixes: d28d6d2e37 ("net: lan966x: add port module support")
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-26 15:45:49 +00:00
David S. Miller
8199d0c6ad Merge branch 'dev_addr-const-fixes'
Jakub Kicinski says:

====================
ethernet: fix some esoteric drivers after netdev->dev_addr constification

Looking at recent fixes for drivers which don't get included with
allmodconfig builds I thought it's worth grepping for more instances of:

  dev->dev_addr\[.*\] =

This set contains the fixes.

v2: add last 3 patches which fix drivers for the RiscPC ARM platform.
Thanks to Arnd Bergmann for explaining how to build test that.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-26 15:40:02 +00:00
Jakub Kicinski
8eb86fc2f4 ethernet: seeq/ether3: don't write directly to netdev->dev_addr
netdev->dev_addr is const now.

Compile tested rpc_defconfig w/ GCC 8.5.

Fixes: adeef3e321 ("net: constify netdev->dev_addr")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-26 15:40:01 +00:00
Jakub Kicinski
5518c5246b ethernet: 8390/etherh: don't write directly to netdev->dev_addr
netdev->dev_addr is const now.

Compile tested rpc_defconfig w/ GCC 8.5.

Fixes: adeef3e321 ("net: constify netdev->dev_addr")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-26 15:40:01 +00:00
Jakub Kicinski
98ef22bbae ethernet: i825xx: don't write directly to netdev->dev_addr
netdev->dev_addr is const now.

Compile tested rpc_defconfig w/ GCC 8.5.

Fixes: adeef3e321 ("net: constify netdev->dev_addr")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-26 15:40:01 +00:00
Jakub Kicinski
7f6ec2b2f0 ethernet: broadcom/sb1250-mac: don't write directly to netdev->dev_addr
netdev->dev_addr is const now.

Compile tested bigsur_defconfig and sb1250_swarm_defconfig.

Fixes: adeef3e321 ("net: constify netdev->dev_addr")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-26 15:40:01 +00:00
Jakub Kicinski
14ba66a60f ethernet: tundra: don't write directly to netdev->dev_addr
netdev->dev_addr is const now.

Maintain the questionable offsetting in ndo_set_mac_address.

Compile tested holly_defconfig and mpc7448_hpc2_defconfig.

Fixes: adeef3e321 ("net: constify netdev->dev_addr")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-26 15:40:01 +00:00
Jakub Kicinski
007c95120d ethernet: 3com/typhoon: don't write directly to netdev->dev_addr
This driver casts off the const and writes directly to netdev->dev_addr.
This will result in a MAC address tree corruption and a warning.

Compile tested ppc6xx_defconfig.

Fixes: adeef3e321 ("net: constify netdev->dev_addr")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-26 15:40:01 +00:00
Tong Zhang
7fde14d705 drm/privacy-screen: honor acpi=off in detect_thinkpad_privacy_screen
when acpi=off is provided in bootarg, kernel crash with

[    1.252739] BUG: kernel NULL pointer dereference, address: 0000000000000018
[    1.258308] Call Trace:
[    1.258490]  ? acpi_walk_namespace+0x147/0x147
[    1.258770]  acpi_get_devices+0xe4/0x137
[    1.258921]  ? drm_core_init+0xc0/0xc0 [drm]
[    1.259108]  detect_thinkpad_privacy_screen+0x5e/0xa8 [drm]
[    1.259337]  drm_privacy_screen_lookup_init+0xe/0xe85 [drm]

The reason is that acpi_walk_namespace expects acpi related stuff
initialized but in fact it wouldn't when acpi is set to off. In this case
we should honor acpi=off in detect_thinkpad_privacy_screen().

Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220123091004.763775-1-ztong0001@gmail.com
2022-01-26 15:25:50 +01:00
Namhyung Kim
c5de60cd62 perf/core: Fix cgroup event list management
The active cgroup events are managed in the per-cpu cgrp_cpuctx_list.
This list is only accessed from current cpu and not protected by any
locks.  But from the commit ef54c1a476 ("perf: Rework
perf_event_exit_event()"), it's possible to access (actually modify)
the list from another cpu.

In the perf_remove_from_context(), it can remove an event from the
context without an IPI when the context is not active.  This is not
safe with cgroup events which can have some active events in the
context even if ctx->is_active is 0 at the moment.  The target cpu
might be in the middle of list iteration at the same time.

If the event is enabled when it's about to be closed, it might call
perf_cgroup_event_disable() and list_del() with the cgrp_cpuctx_list
on a different cpu.

This resulted in a crash due to an invalid list pointer access during
the cgroup list traversal on the cpu which the event belongs to.

Let's fallback to IPI to access the cgrp_cpuctx_list from that cpu.
Similarly, perf_install_in_context() should use IPI for the cgroup
events too.

Fixes: ef54c1a476 ("perf: Rework perf_event_exit_event()")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220124195808.2252071-1-namhyung@kernel.org
2022-01-26 15:06:06 +01:00
James Clark
961c391217 perf: Always wake the parent event
When using per-process mode and event inheritance is set to true,
forked processes will create a new perf events via inherit_event() ->
perf_event_alloc(). But these events will not have ring buffers
assigned to them. Any call to wakeup will be dropped if it's called on
an event with no ring buffer assigned because that's the object that
holds the wakeup list.

If the child event is disabled due to a call to
perf_aux_output_begin() or perf_aux_output_end(), the wakeup is
dropped leaving userspace hanging forever on the poll.

Normally the event is explicitly re-enabled by userspace after it
wakes up to read the aux data, but in this case it does not get woken
up so the event remains disabled.

This can be reproduced when using Arm SPE and 'stress' which forks once
before running the workload. By looking at the list of aux buffers read,
it's apparent that they stop after the fork:

  perf record -e arm_spe// -vvv -- stress -c 1

With this patch applied they continue to be printed. This behaviour
doesn't happen when using systemwide or per-cpu mode.

Reported-by: Ruben Ayrapetyan <Ruben.Ayrapetyan@arm.com>
Signed-off-by: James Clark <james.clark@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20211206113840.130802-2-james.clark@arm.com
2022-01-26 15:06:06 +01:00
Lukas Wunner
2dd8a74fdd serial: core: Initialize rs485 RTS polarity already on probe
RTS polarity of rs485-enabled ports is currently initialized on uart
open via:

tty_port_open()
  tty_port_block_til_ready()
    tty_port_raise_dtr_rts()  # if (C_BAUD(tty))
      uart_dtr_rts()
        uart_port_dtr_rts()

There's at least three problems here:

First, if no baud rate is set, RTS polarity is not initialized.
That's the right thing to do for rs232, but not for rs485, which
requires that RTS is deasserted unconditionally.

Second, if the DeviceTree property "linux,rs485-enabled-at-boot-time" is
present, RTS should be deasserted as early as possible, i.e. on probe.
Otherwise it may remain asserted until first open.

Third, even though RTS is deasserted on open and close, it may
subsequently be asserted by uart_throttle(), uart_unthrottle() or
uart_set_termios() because those functions aren't rs485-aware.
(Only uart_tiocmset() is.)

To address these issues, move RTS initialization from uart_port_dtr_rts()
to uart_configure_port().  Prevent subsequent modification of RTS
polarity by moving the existing rs485 check from uart_tiocmget() to
uart_update_mctrl().

That way, RTS is initialized on probe and then remains unmodified unless
the uart transmits data.  If rs485 is enabled at runtime (instead of at
boot) through a TIOCSRS485 ioctl(), RTS is initialized by the uart
driver's ->rs485_config() callback and then likewise remains unmodified.

The PL011 driver initializes RTS on uart open and prevents subsequent
modification in its ->set_mctrl() callback.  That code is obsoleted by
the present commit, so drop it.

Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Su Bao Cheng <baocheng.su@siemens.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/2d2acaf3a69e89b7bf687c912022b11fd29dfa1e.1642909284.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 14:53:12 +01:00
Jochen Mades
62f676ff78 serial: pl011: Fix incorrect rs485 RTS polarity on set_mctrl
Commit 8d47923772 ("serial: amba-pl011: add RS485 support") sought to
keep RTS deasserted on set_mctrl if rs485 is enabled.  However it did so
only if deasserted RTS polarity is high.  Fix it in case it's low.

Fixes: 8d47923772 ("serial: amba-pl011: add RS485 support")
Cc: stable@vger.kernel.org # v5.15+
Cc: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: Jochen Mades <jochen@mades.net>
[lukas: copyedit commit message, add stable designation]
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/85fa3323ba8c307943969b7343e23f34c3e652ba.1642909284.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 14:53:12 +01:00
Valentin Caron
037b91ec77 serial: stm32: fix software flow control transfer
x_char is ignored by stm32_usart_start_tx() when xmit buffer is empty.

Fix start_tx condition to allow x_char to be sent.

Fixes: 48a6092fb4 ("serial: stm32-usart: Add STM32 USART Driver")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20220111164441.6178-3-valentin.caron@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 14:52:49 +01:00
Valentin Caron
d3d079bde0 serial: stm32: prevent TDR register overwrite when sending x_char
When sending x_char in stm32_usart_transmit_chars(), driver can overwrite
the value of TDR register by the value of x_char. If this happens, the
previous value that was present in TDR register will not be sent through
uart.

This code checks if the previous value in TDR register is sent before
writing the x_char value into register.

Fixes: 48a6092fb4 ("serial: stm32-usart: Add STM32 USART Driver")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20220111164441.6178-2-valentin.caron@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 14:52:44 +01:00
daniel.starke@siemens.com
8838b2af23 tty: n_gsm: fix SW flow control encoding/handling
n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010.
See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516
The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to
the newer 27.010 here. Chapter 5.2.7.3 states that DC1 (XON) and DC3 (XOFF)
are the control characters defined in ISO/IEC 646. These shall be quoted if
seen in the data stream to avoid interpretation as flow control characters.

ISO/IEC 646 refers to the set of ISO standards described as the ISO
7-bit coded character set for information interchange. Its final version
is also known as ITU T.50.
See https://www.itu.int/rec/T-REC-T.50-199209-I/en

To abide the standard it is needed to quote DC1 and DC3 correctly if these
are seen as data bytes and not as control characters. The current
implementation already tries to enforce this but fails to catch all
defined cases. 3GPP 27.010 chapter 5.2.7.3 clearly states that the most
significant bit shall be ignored for DC1 and DC3 handling. The current
implementation handles only the case with the most significant bit set 0.
Cases in which DC1 and DC3 have the most significant bit set 1 are left
unhandled.

This patch fixes this by masking the data bytes with ISO_IEC_646_MASK (only
the 7 least significant bits set 1) before comparing them with XON
(a.k.a. DC1) and XOFF (a.k.a. DC3) when testing which byte values need
quotation via byte stuffing.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220120101857.2509-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 14:51:42 +01:00
Robert Hancock
d06b1cf282 serial: 8250: of: Fix mapped region size when using reg-offset property
8250_of supports a reg-offset property which is intended to handle
cases where the device registers start at an offset inside the region
of memory allocated to the device. The Xilinx 16550 UART, for which this
support was initially added, requires this. However, the code did not
adjust the overall size of the mapped region accordingly, causing the
driver to request an area of memory past the end of the device's
allocation. For example, if the UART was allocated an address of
0xb0130000, size of 0x10000 and reg-offset of 0x1000 in the device
tree, the region of memory reserved was b0131000-b0140fff, which caused
the driver for the region starting at b0140000 to fail to probe.

Fix this by subtracting reg-offset from the mapped region size.

Fixes: b912b5e2cf ([POWERPC] Xilinx: of_serial support for Xilinx uart 16550.)
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Link: https://lore.kernel.org/r/20220112194214.881844-1-robert.hancock@calian.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 14:50:52 +01:00
Arnaud Pouliquen
db7f19c0aa tty: rpmsg: Fix race condition releasing tty port
The tty_port struct is part of the rpmsg_tty_port structure.
The issue is that the rpmsg_tty_port structure is freed on
rpmsg_tty_remove while it is still referenced in the tty_struct.
Its release is not predictable due to workqueues.

For instance following ftrace shows that rpmsg_tty_close is called after
rpmsg_tty_release_cport:

     nr_test.sh-389     [000] .....   212.093752: rpmsg_tty_remove <-rpmsg_dev_
remove
             cat-1191    [001] .....   212.095697: tty_release <-__fput
      nr_test.sh-389     [000] .....   212.099166: rpmsg_tty_release_cport <-rpm
sg_tty_remove
             cat-1191    [001] .....   212.115352: rpmsg_tty_close <-tty_release
             cat-1191    [001] .....   212.115371: release_tty <-tty_release_str

As consequence, the port must be free only when user has released the TTY
interface.

This path :
- Introduce the .destruct port tty ops function to release the allocated
  rpmsg_tty_port structure.
- Introduce the .hangup tty ops function to call tty_port_hangup.
- Manages the tty port refcounting to trig the .destruct port ops,
- Introduces the rpmsg_tty_cleanup function to ensure that the TTY is
  removed before decreasing the port refcount.

Fixes: 7c0408d805 ("tty: add rpmsg driver")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Link: https://lore.kernel.org/r/20220104163545.34710-1-arnaud.pouliquen@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 14:50:26 +01:00
Maciej W. Rozycki
f23653fe64 tty: Partially revert the removal of the Cyclades public API
Fix a user API regression introduced with commit f76edd8f7c ("tty:
cyclades, remove this orphan"), which removed a part of the API and
caused compilation errors for user programs using said part, such as
GCC 9 in its libsanitizer component[1]:

.../libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cc:160:10: fatal error: linux/cyclades.h: No such file or directory
  160 | #include <linux/cyclades.h>
      |          ^~~~~~~~~~~~~~~~~~
compilation terminated.
make[4]: *** [Makefile:664: sanitizer_platform_limits_posix.lo] Error 1

As the absolute minimum required bring `struct cyclades_monitor' and
ioctl numbers back then so as to make the library build again.  Add a
preprocessor warning as to the obsolescence of the features provided.

References:

[1] GCC PR sanitizer/100379, "cyclades.h is removed from linux kernel
    header files", <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100379>

Fixes: f76edd8f7c ("tty: cyclades, remove this orphan")
Cc: stable@vger.kernel.org # v5.13+
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Maciej W. Rozycki <macro@embecosm.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.20.2201260733430.11348@tpp.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 14:49:46 +01:00
Cameron Williams
152d1afa83 tty: Add support for Brainboxes UC cards.
This commit adds support for the some of the Brainboxes PCI range of
cards, including the UC-101, UC-235/246, UC-257, UC-268, UC-275/279,
UC-302, UC-310, UC-313, UC-320/324, UC-346, UC-357, UC-368
and UC-420/431.

Signed-off-by: Cameron Williams <cang1@live.co.uk>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/AM5PR0202MB2564688493F7DD9B9C610827C45E9@AM5PR0202MB2564.eurprd02.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 14:49:29 +01:00
Yu Kuai
592ee1197f blk-mq: fix missing blk_account_io_done() in error path
If blk_mq_request_issue_directly() failed from
blk_insert_cloned_request(), the request will be accounted start.
Currently, blk_insert_cloned_request() is only called by dm, and such
request won't be accounted done by dm.

In normal path, io will be accounted start from blk_mq_bio_to_request(),
when the request is allocated, and such io will be accounted done from
__blk_mq_end_request_acct() whether it succeeded or failed. Thus add
blk_account_io_done() to fix the problem.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220126012132.3111551-1-yukuai3@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-01-26 06:34:41 -07:00
Greg Kroah-Hartman
6a7b9f002e Revert "tty: serial: Use fifo in 8250 console driver"
This reverts commit 5021d709b3.

The patch is still a bit buggy, and this breaks some other hardware
types.  It needs to be resubmitted in a non-buggy way, and make sure the
other hardware types also continue to work properly.

Fixes: 5021d709b3 ("tty: serial: Use fifo in 8250 console driver")
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/Ye/1+Z8mEzbKbrqG@linutronix.de
Link: https://lore.kernel.org/r/a1ac6254-f79e-d131-fa2a-c7ad714c6d4a@nvidia.com
Cc: Wander Lairson Costa <wander@redhat.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 14:33:58 +01:00
Pawel Laszczak
79aa3e19fe usb: cdnsp: Fix segmentation fault in cdns_lost_power function
CDNSP driver read not initialized cdns->otg_v0_regs
which lead to segmentation fault. Patch fixes this issue.

Fixes: 2cf2581cd2 ("usb: cdns3: add power lost support for system resume")
cc: <stable@vger.kernel.org>
Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Link: https://lore.kernel.org/r/20220111090737.10345-1-pawell@gli-login.cadence.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 14:11:16 +01:00
Amelie Delaunay
ac55d16385 usb: dwc2: gadget: don't try to disable ep0 in dwc2_hsotg_suspend
Calling dwc2_hsotg_ep_disable on ep0 (in/out) will lead to the following
logs before returning -EINVAL:
dwc2 49000000.usb-otg: dwc2_hsotg_ep_disable: called for ep0
dwc2 49000000.usb-otg: dwc2_hsotg_ep_disable: called for ep0

To avoid these two logs while suspending, start disabling the endpoint
from the index 1, as done in dwc2_hsotg_udc_stop:

	/* all endpoints should be shutdown */
	for (ep = 1; ep < hsotg->num_of_eps; ep++) {
		if (hsotg->eps_in[ep])
			dwc2_hsotg_ep_disable_lock(&hsotg->eps_in[ep]->ep);
		if (hsotg->eps_out[ep])
			dwc2_hsotg_ep_disable_lock(&hsotg->eps_out[ep]->ep);
	}

Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/20211207130101.270314-1-amelie.delaunay@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 13:49:35 +01:00
Miles Chen
26d81b2924 usb: gadget: at91_udc: fix incorrect print type
Fix a build error observed with ARCH=arm DEFCONFIG=allmodconfig build.

drivers/usb/gadget/udc/at91_udc.h:174:42: error: format '%d' expects argument of type 'int', but argument 3 has type 'struct gpio_desc *' [-Werror=format=]

Fixes: 4a555f2b8d ("usb: gadget: at91_udc: Convert to GPIO descriptors")
Reviewed-by: Macpaul Lin <macpaul.lin@mediatek.com>
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Link: https://lore.kernel.org/r/20220119020849.25732-1-miles.chen@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 13:45:42 +01:00
Robert Hancock
2cc9b1c93b usb: dwc3: xilinx: Fix error handling when getting USB3 PHY
The code that looked up the USB3 PHY was ignoring all errors other than
EPROBE_DEFER in an attempt to handle the PHY not being present. Fix and
simplify the code by using devm_phy_optional_get and dev_err_probe so
that a missing PHY is not treated as an error and unexpected errors
are handled properly.

Fixes: 84770f028f ("usb: dwc3: Add driver for Xilinx platforms")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Link: https://lore.kernel.org/r/20220126000253.1586760-3-robert.hancock@calian.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 13:44:50 +01:00
Robert Hancock
9678f3361a usb: dwc3: xilinx: Skip resets and USB3 register settings for USB2.0 mode
It appears that the PIPE clock should not be selected when only USB 2.0
is being used in the design and no USB 3.0 reference clock is used.
Also, the core resets are not required if a USB3 PHY is not in use, and
will break things if USB3 is actually used but the PHY entry is not
listed in the device tree.

Skip core resets and register settings that are only required for
USB3 mode when no USB3 PHY is specified in the device tree.

Fixes: 84770f028f ("usb: dwc3: Add driver for Xilinx platforms")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Link: https://lore.kernel.org/r/20220126000253.1586760-2-robert.hancock@calian.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 13:44:32 +01:00
Frank Li
9df478463d usb: xhci-plat: fix crash when suspend if remote wake enable
Crashed at i.mx8qm platform when suspend if enable remote wakeup

Internal error: synchronous external abort: 96000210 [#1] PREEMPT SMP
Modules linked in:
CPU: 2 PID: 244 Comm: kworker/u12:6 Not tainted 5.15.5-dirty #12
Hardware name: Freescale i.MX8QM MEK (DT)
Workqueue: events_unbound async_run_entry_fn
pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : xhci_disable_hub_port_wake.isra.62+0x60/0xf8
lr : xhci_disable_hub_port_wake.isra.62+0x34/0xf8
sp : ffff80001394bbf0
x29: ffff80001394bbf0 x28: 0000000000000000 x27: ffff00081193b578
x26: ffff00081193b570 x25: 0000000000000000 x24: 0000000000000000
x23: ffff00081193a29c x22: 0000000000020001 x21: 0000000000000001
x20: 0000000000000000 x19: ffff800014e90490 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
x14: 0000000000000000 x13: 0000000000000002 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000000960 x9 : ffff80001394baa0
x8 : ffff0008145d1780 x7 : ffff0008f95b8e80 x6 : 000000001853b453
x5 : 0000000000000496 x4 : 0000000000000000 x3 : ffff00081193a29c
x2 : 0000000000000001 x1 : 0000000000000000 x0 : ffff000814591620
Call trace:
 xhci_disable_hub_port_wake.isra.62+0x60/0xf8
 xhci_suspend+0x58/0x510
 xhci_plat_suspend+0x50/0x78
 platform_pm_suspend+0x2c/0x78
 dpm_run_callback.isra.25+0x50/0xe8
 __device_suspend+0x108/0x3c0

The basic flow:
	1. run time suspend call xhci_suspend, xhci parent devices gate the clock.
        2. echo mem >/sys/power/state, system _device_suspend call xhci_suspend
        3. xhci_suspend call xhci_disable_hub_port_wake, which access register,
	   but clock already gated by run time suspend.

This problem was hidden by power domain driver, which call run time resume before it.

But the below commit remove it and make this issue happen.
	commit c1df456d0f ("PM: domains: Don't runtime resume devices at genpd_prepare()")

This patch call run time resume before suspend to make sure clock is on
before access register.

Reviewed-by: Peter Chen <peter.chen@kernel.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Testeb-by: Abel Vesa <abel.vesa@nxp.com>
Link: https://lore.kernel.org/r/20220110172738.31686-1-Frank.Li@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 13:42:33 +01:00
Jon Hunter
2e3dd4a624 usb: common: ulpi: Fix crash in ulpi_match()
Commit 7495af9308 ("ARM: multi_v7_defconfig: Enable drivers for
DragonBoard 410c") enables the CONFIG_PHY_QCOM_USB_HS for the ARM
multi_v7_defconfig. Enabling this Kconfig is causing the kernel to crash
on the Tegra20 Ventana platform in the ulpi_match() function.

The Qualcomm USB HS PHY driver that is enabled by CONFIG_PHY_QCOM_USB_HS,
registers a ulpi_driver but this driver does not provide an 'id_table',
so when ulpi_match() is called on the Tegra20 Ventana platform, it
crashes when attempting to deference the id_table pointer which is not
valid. The Qualcomm USB HS PHY driver uses device-tree for matching the
ULPI driver with the device and so fix this crash by using device-tree
for matching if the id_table is not valid.

Fixes: ef6a7bcfb0 ("usb: ulpi: Support device discovery via DT")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://lore.kernel.org/r/20220117150039.44058-1-jonathanh@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 13:42:05 +01:00
Pavankumar Kondeti
904edf8aeb usb: gadget: f_sourcesink: Fix isoc transfer for USB_SPEED_SUPER_PLUS
Currently when gadget enumerates in super speed plus, the isoc
endpoint request buffer size is not calculated correctly. Fix
this by checking the gadget speed against USB_SPEED_SUPER_PLUS
and update the request buffer size.

Fixes: 90c4d05780 ("usb: fix various gadgets null ptr deref on 10gbps cabling.")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Pavankumar Kondeti <quic_pkondeti@quicinc.com>
Link: https://lore.kernel.org/r/1642820602-20619-1-git-send-email-quic_pkondeti@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 13:41:53 +01:00
Sing-Han Chen
825911492e ucsi_ccg: Check DEV_INT bit only when starting CCG4
CCGx clears Bit 0:Device Interrupt in the INTR_REG
if CCGx is reset successfully. However, there might
be a chance that other bits in INTR_REG are not
cleared due to internal data queued in PPM. This case
misleads the driver that CCGx reset failed.

The commit checks bit 0 in INTR_REG and ignores other
bits. The ucsi driver would reset PPM later.

Fixes: 247c554a14 ("usb: typec: ucsi: add support for Cypress CCGx")
Cc: stable@vger.kernel.org
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Sing-Han Chen <singhanc@nvidia.com>
Signed-off-by: Wayne Chang <waynec@nvidia.com>
Link: https://lore.kernel.org/r/20220112094143.628610-1-waynec@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-26 13:41:19 +01:00
Marc Zyngier
c733ebb7cb irqchip/gic-v3-its: Reset each ITS's BASERn register before probe
A recent bug report outlined that the way GICv4.1 is handled across
kexec is pretty bad. We can end-up in a situation where ITSs share
memory (this is the case when SVPET==1) and reprogram the base
registers, creating a situation where ITSs that are part of a given
affinity group see different pointers. Which is illegal. Boo.

In order to restore some sanity, reset the BASERn registers to 0
*before* probing any ITS. Although this isn't optimised at all,
this is only a once-per-boot cost, which shouldn't show up on
anyone's radar.

Cc: Jay Chen <jkchen@linux.alibaba.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Link: https://lore.kernel.org/r/20211216190315.GA14220@lpieralisi
Link: https://lore.kernel.org/r/20220124133809.1291195-1-maz@kernel.org
2022-01-26 11:10:28 +00:00