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Linux kernel
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Commit f1e525009493 ("x86/boot: Skip realmode init code when running as
Xen PV guest") missed one code path accessing real_mode_header, leading
to dereferencing NULL when suspending the system under Xen:
[ 348.284004] PM: suspend entry (deep)
[ 348.289532] Filesystems sync: 0.005 seconds
[ 348.291545] Freezing user space processes ... (elapsed 0.000 seconds) done.
[ 348.292457] OOM killer disabled.
[ 348.292462] Freezing remaining freezable tasks ... (elapsed 0.104 seconds) done.
[ 348.396612] printk: Suspending console(s) (use no_console_suspend to debug)
[ 348.749228] PM: suspend devices took 0.352 seconds
[ 348.769713] ACPI: EC: interrupt blocked
[ 348.816077] BUG: kernel NULL pointer dereference, address: 000000000000001c
[ 348.816080] #PF: supervisor read access in kernel mode
[ 348.816081] #PF: error_code(0x0000) - not-present page
[ 348.816083] PGD 0 P4D 0
[ 348.816086] Oops: 0000 [#1] PREEMPT SMP NOPTI
[ 348.816089] CPU: 0 PID: 6764 Comm: systemd-sleep Not tainted 6.1.3-1.fc32.qubes.x86_64 #1
[ 348.816092] Hardware name: Star Labs StarBook/StarBook, BIOS 8.01 07/03/2022
[ 348.816093] RIP: e030:acpi_get_wakeup_address+0xc/0x20
Fix that by adding an optional acpi callback allowing to skip setting
the wakeup address, as in the Xen PV case this will be handled by the
hypervisor anyway.
Fixes: f1e525009493 ("x86/boot: Skip realmode init code when running as Xen PV guest")
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/all/20230117155724.22940-1-jgross%40suse.com
The hypervisor can enable various new features (SEV_FEATURES[1:63]) and start a
SNP guest. Some of these features need guest side implementation. If any of
these features are enabled without it, the behavior of the SNP guest will be
undefined. It may fail booting in a non-obvious way making it difficult to
debug.
Instead of allowing the guest to continue and have it fail randomly later,
detect this early and fail gracefully.
The SEV_STATUS MSR indicates features which the hypervisor has enabled. While
booting, SNP guests should ascertain that all the enabled features have guest
side implementation. In case a feature is not implemented in the guest, the
guest terminates booting with GHCB protocol Non-Automatic Exit(NAE) termination
request event, see "SEV-ES Guest-Hypervisor Communication Block Standardization"
document (currently at https://developer.amd.com/wp-content/resources/56421.pdf),
section "Termination Request".
Populate SW_EXITINFO2 with mask of unsupported features that the hypervisor can
easily report to the user.
More details in the AMD64 APM Vol 2, Section "SEV_STATUS MSR".
[ bp:
- Massage.
- Move snp_check_features() call to C code.
Note: the CC:stable@ aspect here is to be able to protect older, stable
kernels when running on newer hypervisors. Or not "running" but fail
reliably and in a well-defined manner instead of randomly. ]
Fixes: cbd3d4f7c4e5 ("x86/sev: Check SEV-SNP features support")
Signed-off-by: Nikunj A Dadhania <nikunj@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20230118061943.534309-1-nikunj@amd.com
David reported that the recent PCI/MSI rework results in MSI descriptor
leakage under XEN.
This is caused by:
1) The missing MSI_FLAG_FREE_MSI_DESCS flag in the XEN MSI domain info,
which is required now that PCI/MSI delegates descriptor freeing to
the core MSI code.
2) Not disassociating the interrupts on teardown, by setting the
msi_desc::irq to 0. This was not required before because the teardown
was unconditional and did not check whether a MSI descriptor was still
connected to a Linux interrupt.
On further inspection it came to light that the MSI_FLAG_DEV_SYSFS is
missing in the XEN MSI domain info as well to restore the pre 6.2 status
quo.
Add the missing MSI flags and disassociate the MSI descriptor from the
Linux interrupt in the XEN specific teardown function.
Fixes: b2bdda205c0c ("PCI/MSI: Let the MSI core free descriptors")
Fixes: 2f2940d16823 ("genirq/msi: Remove filter from msi_free_descs_free_range()")
Fixes: ffd84485e6be ("PCI/MSI: Let the irq code handle sysfs groups")
Reported-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: David Woodhouse <dwmw@amazon.co.uk>
Link: https://lore.kernel.org/r/871qnunycr.ffs@tglx
The Xen MSI → PIRQ magic does support MSI-X, so advertise it.
(In fact it's better off with MSI-X than MSI, because it's actually
broken by design for 32-bit MSI, since it puts the high bits of the
PIRQ# into the high 32 bits of the MSI message address, instead of the
Extended Destination ID field which is in bits 4-11.
Strictly speaking, this really fixes a much older commit 2e4386eba0c0
("x86/xen: Wrap XEN MSI management into irqdomain") which failed to set
the flag. But that never really mattered until __pci_enable_msix_range()
started to check and bail out early. So in 6.2-rc we see failures e.g.
to bring up networking on an Amazon EC2 m4.16xlarge instance:
[ 41.498694] ena 0000:00:03.0 (unnamed net_device) (uninitialized): Failed to enable MSI-X. irq_cnt -524
[ 41.498705] ena 0000:00:03.0: Can not reserve msix vectors
[ 41.498712] ena 0000:00:03.0: Failed to enable and set the admin interrupts
Side note: This is the first bug found, and first patch tested, by running
Xen guests under QEMU/KVM instead of running under actual Xen.
Fixes: 99f3d2797657 ("PCI/MSI: Reject MSI-X early")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/4bffa69a949bfdc92c4a18e5a1c3cbb3b94a0d32.camel@infradead.org
Baoquan reported that after triggering a crash the subsequent crash-kernel
fails to boot about half of the time. It triggers a NULL pointer
dereference in the periodic tick code.
This happens because the legacy timer interrupt (IRQ0) is resent in
software which happens in soft interrupt (tasklet) context. In this context
get_irq_regs() returns NULL which leads to the NULL pointer dereference.
The reason for the resend is a spurious APIC interrupt on the IRQ0 vector
which is captured and leads to a resend when the legacy timer interrupt is
enabled. This is wrong because the legacy PIC interrupts are level
triggered and therefore should never be resent in software, but nothing
ever sets the IRQ_LEVEL flag on those interrupts, so the core code does not
know about their trigger type.
Ensure that IRQ_LEVEL is set when the legacy PCI interrupts are set up.
Fixes: a4633adcdbc1 ("[PATCH] genirq: add genirq sw IRQ-retrigger")
Reported-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Baoquan He <bhe@redhat.com>
Link: https://lore.kernel.org/r/87mt6rjrra.ffs@tglx
Pull x86 fixes from Borislav Petkov:
- Make sure the poking PGD is pinned for Xen PV as it requires it this
way
- Fixes for two resctrl races when moving a task or creating a new
monitoring group
- Fix SEV-SNP guests running under HyperV where MTRRs are disabled to
not return a UC- type mapping type on memremap() and thus cause a
serious slowdown
- Fix insn mnemonics in bioscall.S now that binutils is starting to fix
confusing insn suffixes
* tag 'x86_urgent_for_v6.2_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: fix poking_init() for Xen PV guests
x86/resctrl: Fix event counts regression in reused RMIDs
x86/resctrl: Fix task CLOSID/RMID update race
x86/pat: Fix pat_x_mtrr_type() for MTRR disabled case
x86/boot: Avoid using Intel mnemonics in AT&T syntax asm
Pull EDAC fixes from Borislav Petkov:
- Fix the EDAC device's confusion in the polling setting units
- Fix a memory leak in highbank's probing function
* tag 'edac_urgent_for_v6.2_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
EDAC/highbank: Fix memory leak in highbank_mc_probe()
EDAC/device: Fix period calculation in edac_device_reset_delay_period()
Commit 3f4c8211d982 ("x86/mm: Use mm_alloc() in poking_init()") broke
the kernel for running as Xen PV guest.
It seems as if the new address space is never activated before being
used, resulting in Xen rejecting to accept the new CR3 value (the PGD
isn't pinned).
Fix that by adding the now missing call of paravirt_arch_dup_mmap() to
poking_init(). That call was previously done by dup_mm()->dup_mmap() and
it is a NOP for all cases but for Xen PV, where it is just doing the
pinning of the PGD.
Fixes: 3f4c8211d982 ("x86/mm: Use mm_alloc() in poking_init()")
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230109150922.10578-1-jgross@suse.com
Pull powerpc fixes from Michael Ellerman:
- Fix a build failure with some versions of ld that have an odd version
string
- Fix incorrect use of mutex in the IMC PMU driver
Thanks to Kajol Jain, Michael Petlan, Ojaswin Mujoo, Peter Zijlstra, and
Yang Yingliang.
* tag 'powerpc-6.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64s/hash: Make stress_hpt_timer_fn() static
powerpc/imc-pmu: Fix use of mutex in IRQs disabled section
powerpc/boot: Fix incorrect version calculation issue in ld_version
When devres_open_group() fails, it returns -ENOMEM without freeing memory
allocated by edac_mc_alloc().
Call edac_mc_free() on the error handling path to avoid a memory leak.
[ bp: Massage commit message. ]
Fixes: a1b01edb2745 ("edac: add support for Calxeda highbank memory controller")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Link: https://lore.kernel.org/r/20221229054825.1361993-1-linmq006@gmail.com
When creating a new monitoring group, the RMID allocated for it may have
been used by a group which was previously removed. In this case, the
hardware counters will have non-zero values which should be deducted
from what is reported in the new group's counts.
resctrl_arch_reset_rmid() initializes the prev_msr value for counters to
0, causing the initial count to be charged to the new group. Resurrect
__rmid_read() and use it to initialize prev_msr correctly.
Unlike before, __rmid_read() checks for error bits in the MSR read so
that callers don't need to.
Fixes: 1d81d15db39c ("x86/resctrl: Move mbm_overflow_count() into resctrl_arch_rmid_read()")
Signed-off-by: Peter Newman <peternewman@google.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20221220164132.443083-1-peternewman@google.com
Pull iommu fixes from Joerg Roedel:
- Core: Fix an iommu-group refcount leak
- Fix overflow issue in IOVA alloc path
- ARM-SMMU fixes from Will:
- Fix VFIO regression on NXP SoCs by reporting IOMMU_CAP_CACHE_COHERENCY
- Fix SMMU shutdown paths to avoid device unregistration race
- Error handling fix for Mediatek IOMMU driver
* tag 'iommu-fixes-v6.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/mediatek-v1: Fix an error handling path in mtk_iommu_v1_probe()
iommu/iova: Fix alloc iova overflows issue
iommu: Fix refcount leak in iommu_device_claim_dma_owner
iommu/arm-smmu-v3: Don't unregister on shutdown
iommu/arm-smmu: Don't unregister on shutdown
iommu/arm-smmu: Report IOMMU_CAP_CACHE_COHERENCY even betterer
stress_hpt_timer_fn() is only used in hash_utils.c, make it static.
Fixes: 6b34a099faa1 ("powerpc/64s/hash: add stress_hpt kernel boot option to increase hash faults")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221228093603.3166599-1-yangyingliang@huawei.com
Fix period calculation in case user sets a value of 1000. The input of
round_jiffies_relative() should be in jiffies and not in milli-seconds.
[ bp: Use the same code pattern as in edac_device_workq_setup() for
clarity. ]
Fixes: c4cf3b454eca ("EDAC: Rework workqueue handling")
Signed-off-by: Eliav Farber <farbere@amazon.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20221020124458.22153-1-farbere@amazon.com
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