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FNAME(invlpg)() and kvm_mmu_invalidate_gva() take a gva_t, i.e. unsigned
long, as the type of the address to invalidate. On 32-bit kernels, the
upper 32 bits of the GPA will get dropped when an L2 GPA address is
invalidated in the shadowed nested TDP MMU.
Convert it to u64 to fix the problem.
Reported-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Link: https://lore.kernel.org/r/20230216154115.710033-2-jiangshanlai@gmail.com
[sean: tweak changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>
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Pull kvm fixes from Paolo Bonzini:
"ARM64:
- Address a rather annoying bug w.r.t. guest timer offsetting. The
synchronization of timer offsets between vCPUs was broken, leading
to inconsistent timer reads within the VM.
x86:
- New tests for the slow path of the EVTCHNOP_send Xen hypercall
- Add missing nVMX consistency checks for CR0 and CR4
- Fix bug that broke AMD GATag on 512 vCPU machines
Selftests:
- Skip hugetlb tests if huge pages are not available
- Sync KVM exit reasons"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: selftests: Sync KVM exit reasons in selftests
KVM: selftests: Add macro to generate KVM exit reason strings
KVM: selftests: Print expected and actual exit reason in KVM exit reason assert
KVM: selftests: Make vCPU exit reason test assertion common
KVM: selftests: Add EVTCHNOP_send slow path test to xen_shinfo_test
KVM: selftests: Use enum for test numbers in xen_shinfo_test
KVM: selftests: Add helpers to make Xen-style VMCALL/VMMCALL hypercalls
KVM: selftests: Move the guts of kvm_hypercall() to a separate macro
KVM: SVM: WARN if GATag generation drops VM or vCPU ID information
KVM: SVM: Modify AVIC GATag to support max number of 512 vCPUs
KVM: SVM: Fix a benign off-by-one bug in AVIC physical table mask
selftests: KVM: skip hugetlb tests if huge pages are not available
KVM: VMX: Use tabs instead of spaces for indentation
KVM: VMX: Fix indentation coding style issue
KVM: nVMX: remove unnecessary #ifdef
KVM: nVMX: add missing consistency checks for CR0 and CR4
KVM: arm64: timers: Convert per-vcpu virtual offset to a global value
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Commit 21b56c847753 ("iov_iter: get rid of separate bvec and xarray
callbacks") removed the calls to memcpy_page_flushcache().
In addition, memcpy_page_flushcache() uses the deprecated
kmap_atomic().
Remove the unused x86 memcpy_page_flushcache() implementation and
also get rid of one more kmap_atomic() user.
[ dhansen: tweak changelog ]
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20221230-kmap-x86-v1-1-15f1ecccab50%40intel.com
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All kvm_arch_vm_ioctl() implementations now only deal with "int"
types as return values, so we can change the return type of these
functions to use "int" instead of "long".
Signed-off-by: Thomas Huth <thuth@redhat.com>
Acked-by: Anup Patel <anup@brainfault.org>
Message-Id: <20230208140105.655814-7-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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The KVM_GET_NR_MMU_PAGES ioctl is quite questionable on 64-bit hosts
since it fails to return the full 64 bits of the value that can be
set with the corresponding KVM_SET_NR_MMU_PAGES call. Its "long" return
value is truncated into an "int" in the kvm_arch_vm_ioctl() function.
Since this ioctl also never has been used by userspace applications
(QEMU, Google's internal VMM, kvmtool and CrosVM have been checked),
it's likely the best if we remove this badly designed ioctl before
anybody really tries to use it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230208140105.655814-4-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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FLUSH_L1D was already added in 11e34e64e4103, but the feature is not
visible to userspace yet.
The bit definition:
CPUID.(EAX=7,ECX=0):EDX[bit 28]
If the feature is supported by the host, kvm should support it too so
that userspace can choose whether to expose it to the guest or not.
One disadvantage of not exposing it is that the guest will report
a non existing vulnerability in
/sys/devices/system/cpu/vulnerabilities/mmio_stale_data
because the mitigation is present only if the guest supports
(FLUSH_L1D and MD_CLEAR) or FB_CLEAR.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230201132905.549148-4-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Expose IA32_FLUSH_CMD to the guest if the guest CPUID enumerates
support for this MSR. As with IA32_PRED_CMD, permission for
unintercepted writes to this MSR will be granted to the guest after
the first non-zero write.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230201132905.549148-3-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Expose IA32_FLUSH_CMD to the guest if the guest CPUID enumerates
support for this MSR. As with IA32_PRED_CMD, permission for
unintercepted writes to this MSR will be granted to the guest after
the first non-zero write.
Co-developed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230201132905.549148-2-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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cmdline_find_option() may fail before doing any initialization of
the buffer array. This may lead to unpredictable results when the same
buffer is used later in calls to strncmp() function. Fix the issue by
returning early if cmdline_find_option() returns an error.
Found by Linux Verification Center (linuxtesting.org) with static
analysis tool SVACE.
Fixes: aca20d546214 ("x86/mm: Add support to make use of Secure Memory Encryption")
Signed-off-by: Nikita Zhandarovich <n.zhandarovich@fintech.ru>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20230306160656.14844-1-n.zhandarovich@fintech.ru
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The December 2022 edition of the Intel Instruction Set Extensions manual
defined that the split lock disable bit in the IA32_CORE_CAPABILITIES MSR
is (and retrospectively always has been) architectural.
Remove all the model specific checks except for Ice Lake variants which are
still needed because these CPU models do not enumerate presence of the
IA32_CORE_CAPABILITIES MSR.
Originally-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/lkml/20220701131958.687066-1-fenghua.yu@intel.com/t/#mada243bee0915532a6adef6a9e32d244d1a9aef4
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The AutoIBRS bit gets set only on the BSP as part of determining which
mitigation to enable on AMD. Setting on the APs relies on the
circumstance that the APs get booted through the trampoline and EFER
- the MSR which contains that bit - gets replicated on every AP from the
BSP.
However, this can change in the future and considering the security
implications of this bit not being set on every CPU, make sure it is set
by verifying EFER later in the boot process and on every AP.
Reported-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20230224185257.o3mcmloei5zqu7wa@treble
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__mon_event_count() does the per-RMID, per-domain work for
user-initiated event count reads and the initialization of new monitor
groups.
In the initialization case, after resctrl_arch_reset_rmid() calls
__rmid_read() to record an initial count for a new monitor group, it
immediately calls resctrl_arch_rmid_read(). This re-read of the hardware
counter is unnecessary and the following computations are ignored by the
caller during initialization.
Following return from resctrl_arch_reset_rmid(), just clear the
mbm_state and return. This involves moving the mbm_state lookup into the
rr->first case, as it's not needed for regular event count reads: the
QOS_L3_OCCUP_EVENT_ID case was redundant with the accumulating logic at
the end of the function.
Signed-off-by: Peter Newman <peternewman@google.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/all/20221220164132.443083-2-peternewman%40google.com
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As a temporary storage, staged_config[] in rdt_domain should be cleared
before and after it is used. The stale value in staged_config[] could
cause an MSR access error.
Here is a reproducer on a system with 16 usable CLOSIDs for a 15-way L3
Cache (MBA should be disabled if the number of CLOSIDs for MB is less than
16.) :
mount -t resctrl resctrl -o cdp /sys/fs/resctrl
mkdir /sys/fs/resctrl/p{1..7}
umount /sys/fs/resctrl/
mount -t resctrl resctrl /sys/fs/resctrl
mkdir /sys/fs/resctrl/p{1..8}
An error occurs when creating resource group named p8:
unchecked MSR access error: WRMSR to 0xca0 (tried to write 0x00000000000007ff) at rIP: 0xffffffff82249142 (cat_wrmsr+0x32/0x60)
Call Trace:
<IRQ>
__flush_smp_call_function_queue+0x11d/0x170
__sysvec_call_function+0x24/0xd0
sysvec_call_function+0x89/0xc0
</IRQ>
<TASK>
asm_sysvec_call_function+0x16/0x20
When creating a new resource control group, hardware will be configured
by the following process:
rdtgroup_mkdir()
rdtgroup_mkdir_ctrl_mon()
rdtgroup_init_alloc()
resctrl_arch_update_domains()
resctrl_arch_update_domains() iterates and updates all resctrl_conf_type
whose have_new_ctrl is true. Since staged_config[] holds the same values as
when CDP was enabled, it will continue to update the CDP_CODE and CDP_DATA
configurations. When group p8 is created, get_config_index() called in
resctrl_arch_update_domains() will return 16 and 17 as the CLOSIDs for
CDP_CODE and CDP_DATA, which will be translated to an invalid register -
0xca0 in this scenario.
Fix it by clearing staged_config[] before and after it is used.
[reinette: re-order commit tags]
Fixes: 75408e43509e ("x86/resctrl: Allow different CODE/DATA configurations to be staged")
Suggested-by: Xin Hao <xhao@linux.alibaba.com>
Signed-off-by: Shawn Wang <shawnwang@linux.alibaba.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Reinette Chatre <reinette.chatre@intel.com>
Cc:stable@vger.kernel.org
Link: https://lore.kernel.org/all/2fad13f49fbe89687fc40e9a5a61f23a28d1507a.1673988935.git.reinette.chatre%40intel.com
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git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fixes from Steven Rostedt:
- Do not allow histogram values to have modifies. They can cause a NULL
pointer dereference if they do.
- Warn if hist_field_name() is passed a NULL. Prevent the NULL pointer
dereference mentioned above.
- Fix invalid address look up race in lookup_rec()
- Define ftrace_stub_graph conditionally to prevent linker errors
- Always check if RCU is watching at all tracepoint locations
* tag 'trace-v6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Make tracepoint lockdep check actually test something
ftrace,kcfi: Define ftrace_stub_graph conditionally
ftrace: Fix invalid address access in lookup_rec() when index is 0
tracing: Check field value in hist_field_name()
tracing: Do not let histogram values have some modifiers
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Rename enable_evmcs to __kvm_is_using_evmcs to match its wrapper, and to
avoid confusion with enabling eVMCS for nested virtualization, i.e. have
"enable eVMCS" be reserved for "enable eVMCS support for L1".
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230211003534.564198-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Wrap enable_evmcs in a helper and stub it out when CONFIG_HYPERV=n in
order to eliminate the static branch nop placeholders. clang-14 is clever
enough to elide the nop, but gcc-12 is not. Stubbing out the key reduces
the size of kvm-intel.ko by ~7.5% (200KiB) when compiled with gcc-12
(there are a _lot_ of VMCS accesses throughout KVM).
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230211003534.564198-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Move the macros that define the set of VMCS controls that are supported
by eVMCS1 from hyperv.h to hyperv.c, i.e. make them "private". The
macros should never be consumed directly by KVM at-large since the "final"
set of supported controls depends on guest CPUID.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230211003534.564198-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Drop FNAME(is_self_change_mapping) and instead rely on
kvm_mmu_hugepage_adjust() to adjust the hugepage accordingly. Prior to
commit 4cd071d13c5c ("KVM: x86/mmu: Move calls to thp_adjust() down a
level"), the hugepage adjustment was done before allocating new shadow
pages, i.e. failed to restrict the hugepage sizes if a new shadow page
resulted in account_shadowed() changing the disallowed hugepage tracking.
Removing FNAME(is_self_change_mapping) fixes a bug reported by Huang Hang
where KVM unnecessarily forces a 4KiB page. FNAME(is_self_change_mapping)
has a defect in that it blindly disables _all_ hugepage mappings rather
than trying to reduce the size of the hugepage. If the guest is writing
to a 1GiB page and the 1GiB is self-referential but a 2MiB page is not,
then KVM can and should create a 2MiB mapping.
Add a comment above the call to kvm_mmu_hugepage_adjust() to call out the
new dependency on adjusting the hugepage size after walking indirect PTEs.
Reported-by: Huang Hang <hhuang@linux.alibaba.com>
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Link: https://lore.kernel.org/r/20221213125538.81209-1-jiangshanlai@gmail.com
[sean: rework changelog after separating out the emulator change]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230202182817.407394-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Move the detection of write #PF to shadow pages, i.e. a fault on a write
to a page table that is being shadowed by KVM that is used to translate
the write itself, from FNAME(is_self_change_mapping) to FNAME(fetch).
There is no need to detect the self-referential write before
kvm_faultin_pfn() as KVM does not consume EMULTYPE_WRITE_PF_TO_SP for
accesses that resolve to "error or no-slot" pfns, i.e. KVM doesn't allow
retrying MMIO accesses or writes to read-only memslots.
Detecting the EMULTYPE_WRITE_PF_TO_SP scenario in FNAME(fetch) will allow
dropping FNAME(is_self_change_mapping) entirely, as the hugepage
interaction can be deferred to kvm_mmu_hugepage_adjust().
Cc: Huang Hang <hhuang@linux.alibaba.com>
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Link: https://lore.kernel.org/r/20221213125538.81209-1-jiangshanlai@gmail.com
[sean: split to separate patch, write changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230202182817.407394-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Use a new EMULTYPE flag, EMULTYPE_WRITE_PF_TO_SP, to track page faults
on self-changing writes to shadowed page tables instead of propagating
that information to the emulator via a semi-persistent vCPU flag. Using
a flag in "struct kvm_vcpu_arch" is confusing, especially as implemented,
as it's not at all obvious that clearing the flag only when emulation
actually occurs is correct.
E.g. if KVM sets the flag and then retries the fault without ever getting
to the emulator, the flag will be left set for future calls into the
emulator. But because the flag is consumed if and only if both
EMULTYPE_PF and EMULTYPE_ALLOW_RETRY_PF are set, and because
EMULTYPE_ALLOW_RETRY_PF is deliberately not set for direct MMUs, emulated
MMIO, or while L2 is active, KVM avoids false positives on a stale flag
since FNAME(page_fault) is guaranteed to be run and refresh the flag
before it's ultimately consumed by the tail end of reexecute_instruction().
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230202182817.407394-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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A new platform-op was added to Xen to allow obtaining the same VGA
console information PV Dom0 is handed. Invoke the new function and have
the output data processed by xen_init_vga().
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/8f315e92-7bda-c124-71cc-478ab9c5e610@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
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WARN if generating a GATag given a VM ID and vCPU ID doesn't yield the
same IDs when pulling the IDs back out of the tag. Don't bother adding
error handling to callers, this is very much a paranoid sanity check as
KVM fully controls the VM ID and is supposed to reject too-big vCPU IDs.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Tested-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Message-Id: <20230207002156.521736-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Define AVIC_VCPU_ID_MASK based on AVIC_PHYSICAL_MAX_INDEX, i.e. the mask
that effectively controls the largest guest physical APIC ID supported by
x2AVIC, instead of hardcoding the number of bits to 8 (and the number of
VM bits to 24).
The AVIC GATag is programmed into the AMD IOMMU IRTE to provide a
reference back to KVM in case the IOMMU cannot inject an interrupt into a
non-running vCPU. In such a case, the IOMMU notifies software by creating
a GALog entry with the corresponded GATag, and KVM then uses the GATag to
find the correct VM+vCPU to kick. Dropping bit 8 from the GATag results
in kicking the wrong vCPU when targeting vCPUs with x2APIC ID > 255.
Fixes: 4d1d7942e36a ("KVM: SVM: Introduce logic to (de)activate x2AVIC mode")
Cc: stable@vger.kernel.org
Reported-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Tested-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Message-Id: <20230207002156.521736-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Define the "physical table max index mask" as bits 8:0, not 9:0. x2AVIC
currently supports a max of 512 entries, i.e. the max index is 511, and
the inputs to GENMASK_ULL() are inclusive. The bug is benign as bit 9 is
reserved and never set by KVM, i.e. KVM is just clearing bits that are
guaranteed to be zero.
Note, as of this writing, APM "Rev. 3.39-October 2022" incorrectly states
that bits 11:8 are reserved in Table B-1. VMCB Layout, Control Area. I.e.
that table wasn't updated when x2AVIC support was added.
Opportunistically fix the comment for the max AVIC ID to align with the
code, and clean up comment formatting too.
Fixes: 4d1d7942e36a ("KVM: SVM: Introduce logic to (de)activate x2AVIC mode")
Cc: stable@vger.kernel.org
Cc: Alejandro Jimenez <alejandro.j.jimenez@oracle.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Tested-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Message-Id: <20230207002156.521736-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Code indentation should use tabs where possible and miss a '*'.
Signed-off-by: Rong Tao <rongtao@cestc.cn>
Message-Id: <tencent_A492CB3F9592578451154442830EA1B02C07@qq.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Code indentation should use tabs where possible.
Signed-off-by: Rong Tao <rongtao@cestc.cn>
Message-Id: <tencent_31E6ACADCB6915E157CF5113C41803212107@qq.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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nested_vmx_check_controls() has already run by the time KVM checks host state,
so the "host address space size" exit control can only be set on x86-64 hosts.
Simplify the condition at the cost of adding some dead code to 32-bit kernels.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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The effective values of the guest CR0 and CR4 registers may differ from
those included in the VMCS12. In particular, disabling EPT forces
CR4.PAE=1 and disabling unrestricted guest mode forces CR0.PG=CR0.PE=1.
Therefore, checks on these bits cannot be delegated to the processor
and must be performed by KVM.
Reported-by: Reima ISHII <ishiir@g.ecc.u-tokyo.ac.jp>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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A potentially malicious SEV guest can constantly hammer the hypervisor
using this driver to send down requests and thus prevent or at least
considerably hinder other guests from issuing requests to the secure
processor which is a shared platform resource.
Therefore, the host is permitted and encouraged to throttle such guest
requests.
Add the capability to handle the case when the hypervisor throttles
excessive numbers of requests issued by the guest. Otherwise, the VM
platform communication key will be disabled, preventing the guest from
attesting itself.
Realistically speaking, a well-behaved guest should not even care about
throttling. During its lifetime, it would end up issuing a handful of
requests which the hardware can easily handle.
This is more to address the case of a malicious guest. Such guest should
get throttled and if its VMPCK gets disabled, then that's its own
wrongdoing and perhaps that guest even deserves it.
To the implementation: the hypervisor signals with SNP_GUEST_REQ_ERR_BUSY
that the guest requests should be throttled. That error code is returned
in the upper 32-bit half of exitinfo2 and this is part of the GHCB spec
v2.
So the guest is given a throttling period of 1 minute in which it
retries the request every 2 seconds. This is a good default but if it
turns out to not pan out in practice, it can be tweaked later.
For safety, since the encryption algorithm in GHCBv2 is AES_GCM, control
must remain in the kernel to complete the request with the current
sequence number. Returning without finishing the request allows the
guest to make another request but with different message contents. This
is IV reuse, and breaks cryptographic protections.
[ bp:
- Rewrite commit message and do a simplified version.
- The stable tags are supposed to denote that a cleanup should go
upfront before backporting this so that any future fixes to this
can preserve the sanity of the backporter(s). ]
Fixes: d5af44dde546 ("x86/sev: Provide support for SNP guest request NAEs")
Signed-off-by: Dionna Glaze <dionnaglaze@google.com>
Co-developed-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: <stable@kernel.org> # d6fd48eff750 ("virt/coco/sev-guest: Check SEV_SNP attribute at probe time")
Cc: <stable@kernel.org> # 970ab823743f (" virt/coco/sev-guest: Simplify extended guest request handling")
Cc: <stable@kernel.org> # c5a338274bdb ("virt/coco/sev-guest: Remove the disable_vmpck label in handle_guest_request()")
Cc: <stable@kernel.org> # 0fdb6cc7c89c ("virt/coco/sev-guest: Carve out the request issuing logic into a helper")
Cc: <stable@kernel.org> # d25bae7dc7b0 ("virt/coco/sev-guest: Do some code style cleanups")
Cc: <stable@kernel.org> # fa4ae42cc60a ("virt/coco/sev-guest: Convert the sw_exit_info_2 checking to a switch-case")
Link: https://lore.kernel.org/r/20230214164638.1189804-2-dionnaglaze@google.com
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snp_issue_guest_request() checks the value returned by the hypervisor in
sw_exit_info_2 and returns a different error depending on it.
Convert those checks into a switch-case to make it more readable when
more error values are going to be checked in the future.
No functional changes.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20230307192449.24732-8-bp@alien8.de
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Return a specific error code - -ENOSPC - to signal the too small cert
data buffer instead of checking exit code and exitinfo2.
While at it, hoist the *fw_err assignment in snp_issue_guest_request()
so that a proper error value is returned to the callers.
[ Tom: check override_err instead of err. ]
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230307192449.24732-4-bp@alien8.de
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No need to check it on every ioctl. And yes, this is a common SEV driver
but it does only SNP-specific operations currently. This can be
revisited later, when more use cases appear.
No functional changes.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20230307192449.24732-3-bp@alien8.de
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A recent change introduced a flag to queue up errors found during
boot-time polling. These errors will be processed during late init once
the MCE subsystem is fully set up.
A number of sysfs updates call mce_restart() which goes through a subset
of the CPU init flow. This includes polling MCA banks and logging any
errors found. Since the same function is used as boot-time polling,
errors will be queued. However, the system is now past late init, so the
errors will remain queued until another error is found and the workqueue
is triggered.
Call mce_schedule_work() at the end of mce_restart() so that queued
errors are processed.
Fixes: 3bff147b187d ("x86/mce: Defer processing of early errors")
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230301221420.2203184-1-yazen.ghannam@amd.com
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fix from Borislav Petkov:
"A single erratum fix for AMD machines:
- Disable XSAVES on AMD Zen1 and Zen2 machines due to an erratum. No
impact to anything as those machines will fallback to XSAVEC which
is equivalent there"
* tag 'x86_urgent_for_v6.3_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/CPU/AMD: Disable XSAVES on AMD family 0x17
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When CONFIG_FUNCTION_GRAPH_TRACER is disabled, __kcfi_typeid_ftrace_stub_graph
is missing, causing a link failure:
ld.lld: error: undefined symbol: __kcfi_typeid_ftrace_stub_graph
referenced by arch/x86/kernel/ftrace_64.o:(__cfi_ftrace_stub_graph) in archive vmlinux.a
Mark the reference to it as conditional on the same symbol, as
is done on arm64.
Link: https://lore.kernel.org/linux-trace-kernel/20230131093643.3850272-1-arnd@kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
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: "H. Peter Anvin" <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Fixes: 883bbbffa5a4 ("ftrace,kcfi: Separate ftrace_stub() and ftrace_stub_graph()")
See-also: 2598ac6ec493 ("arm64: ftrace: Define ftrace_stub_graph only with FUNCTION_GRAPH_TRACER")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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module_layout manages different types of memory (text, data, rodata, etc.)
in one allocation, which is problematic for some reasons:
1. It is hard to enable CONFIG_STRICT_MODULE_RWX.
2. It is hard to use huge pages in modules (and not break strict rwx).
3. Many archs uses module_layout for arch-specific data, but it is not
obvious how these data are used (are they RO, RX, or RW?)
Improve the scenario by replacing 2 (or 3) module_layout per module with
up to 7 module_memory per module:
MOD_TEXT,
MOD_DATA,
MOD_RODATA,
MOD_RO_AFTER_INIT,
MOD_INIT_TEXT,
MOD_INIT_DATA,
MOD_INIT_RODATA,
and allocating them separately. This adds slightly more entries to
mod_tree (from up to 3 entries per module, to up to 7 entries per
module). However, this at most adds a small constant overhead to
__module_address(), which is expected to be fast.
Various archs use module_layout for different data. These data are put
into different module_memory based on their location in module_layout.
IOW, data that used to go with text is allocated with MOD_MEM_TYPE_TEXT;
data that used to go with data is allocated with MOD_MEM_TYPE_DATA, etc.
module_memory simplifies quite some of the module code. For example,
ARCH_WANTS_MODULES_DATA_IN_VMALLOC is a lot cleaner, as it just uses a
different allocator for the data. kernel/module/strict_rwx.c is also
much cleaner with module_memory.
Signed-off-by: Song Liu <song@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
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The implementation of 'current' on x86 is very intentionally special: it
is a very common thing to look up, and it uses 'this_cpu_read_stable()'
to get the current thread pointer efficiently from per-cpu storage.
And the keyword in there is 'stable': the current thread pointer never
changes as far as a single thread is concerned. Even if when a thread
is preempted, or moved to another CPU, or even across an explicit call
'schedule()' that thread will still have the same value for 'current'.
It is, after all, the kernel base pointer to thread-local storage.
That's why it's stable to begin with, but it's also why it's important
enough that we have that special 'this_cpu_read_stable()' access for it.
So this is all done very intentionally to allow the compiler to treat
'current' as a value that never visibly changes, so that the compiler
can do CSE and combine multiple different 'current' accesses into one.
However, there is obviously one very special situation when the
currently running thread does actually change: inside the scheduler
itself.
So the scheduler code paths are special, and do not have a 'current'
thread at all. Instead there are _two_ threads: the previous and the
next thread - typically called 'prev' and 'next' (or prev_p/next_p)
internally.
So this is all actually quite straightforward and simple, and not all
that complicated.
Except for when you then have special code that is run in scheduler
context, that code then has to be aware that 'current' isn't really a
valid thing. Did you mean 'prev'? Did you mean 'next'?
In fact, even if then look at the code, and you use 'current' after the
new value has been assigned to the percpu variable, we have explicitly
told the compiler that 'current' is magical and always stable. So the
compiler is quite free to use an older (or newer) value of 'current',
and the actual assignment to the percpu storage is not relevant even if
it might look that way.
Which is exactly what happened in the resctl code, that blithely used
'current' in '__resctrl_sched_in()' when it really wanted the new
process state (as implied by the name: we're scheduling 'into' that new
resctl state). And clang would end up just using the old thread pointer
value at least in some configurations.
This could have happened with gcc too, and purely depends on random
compiler details. Clang just seems to have been more aggressive about
moving the read of the per-cpu current_task pointer around.
The fix is trivial: just make the resctl code adhere to the scheduler
rules of using the prev/next thread pointer explicitly, instead of using
'current' in a situation where it just wasn't valid.
That same code is then also used outside of the scheduler context (when
a thread resctl state is explicitly changed), and then we will just pass
in 'current' as that pointer, of course. There is no ambiguity in that
case.
The fix may be trivial, but noticing and figuring out what went wrong
was not. The credit for that goes to Stephane Eranian.
Reported-by: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/lkml/20230303231133.1486085-1-eranian@google.com/
Link: https://lore.kernel.org/lkml/alpine.LFD.2.01.0908011214330.3304@localhost.localdomain/
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Tested-by: Stephane Eranian <eranian@google.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Include <linux/cpu.h> to make sure arch_cpu_idle_dead() matches its
prototype going forward.
Inspired-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Link: https://lore.kernel.org/r/20230214083857.50163-1-philmd@linaro.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
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Before commit 076cbf5d2163 ("x86/xen: don't let xen_pv_play_dead()
return"), in Xen, when a previously offlined CPU was brought back
online, it unexpectedly resumed execution where it left off in the
middle of the idle loop.
There were some hacks to make that work, but the behavior was surprising
as do_idle() doesn't expect an offlined CPU to return from the dead (in
arch_cpu_idle_dead()).
Now that Xen has been fixed, and the arch-specific implementations of
arch_cpu_idle_dead() also don't return, give it a __noreturn attribute.
This will cause the compiler to complain if an arch-specific
implementation might return. It also improves code generation for both
caller and callee.
Also fixes the following warning:
vmlinux.o: warning: objtool: do_idle+0x25f: unreachable instruction
Reported-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/60d527353da8c99d4cf13b6473131d46719ed16d.1676358308.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
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play_dead() doesn't return. Annotate it as such. By extension this
also makes arch_cpu_idle_dead() noreturn.
Link: https://lore.kernel.org/r/f3a069e6869c51ccfdda656b76882363bc9fcfa4.1676358308.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
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After commit 076cbf5d2163 ("x86/xen: don't let xen_pv_play_dead()
return"), play_dead() never returns. Make that more explicit with a
BUG().
BUG() is preferable to unreachable() because BUG() is a more explicit
failure mode and avoids undefined behavior like falling off the edge of
the function into whatever code happens to be next.
Link: https://lore.kernel.org/r/11e6ac1cf10f92967882926e3ac16287b50642f2.1676358308.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
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AMD Erratum 1386 is summarised as:
XSAVES Instruction May Fail to Save XMM Registers to the Provided
State Save Area
This piece of accidental chronomancy causes the %xmm registers to
occasionally reset back to an older value.
Ignore the XSAVES feature on all AMD Zen1/2 hardware. The XSAVEC
instruction (which works fine) is equivalent on affected parts.
[ bp: Typos, move it into the F17h-specific function. ]
Reported-by: Tavis Ormandy <taviso@gmail.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20230307174643.1240184-1-andrew.cooper3@citrix.com
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The stubs for the ancient MCA support (CONFIG_X86_ANCIENT_MCE) are
normally optimized away on 64-bit builds. However, an allmodconfig one
causes the compiler to add sanitizer calls gunk into them and they exist
as constprop calls. Which objtool then complains about:
vmlinux.o: warning: objtool: do_machine_check+0xad8: call to \
pentium_machine_check.constprop.0() leaves .noinstr.text section
due to them missing noinstr. One could tag them "noinstr" but what
should really happen is, they should be forcefully inlined so that all
that gunk gets optimized away and the warning doesn't even have a chance
to fire.
Do so.
No functional changes.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230222191054.4701-1-bp@alien8.de
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Since
ee6d3dd4ed48 ("driver core: make kobj_type constant.")
the driver core allows the usage of const struct kobj_type.
Take advantage of this to constify the structure definition to prevent
modification at runtime.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230217-kobj_type-mce-amd-v1-1-40ef94816444@weissschuh.net
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The two paravirt callbacks .mmu.activate_mm() and .mmu.dup_mmap() are
sharing the same implementations in all cases: for Xen PV guests they
are pinning the PGD of the new mm_struct, and for all other cases they
are a NOP.
In the end, both callbacks are meant to register an address space with
the underlying hypervisor, so there needs to be only a single callback
for that purpose.
So merge them to a common callback .mmu.enter_mmap() (in contrast to the
corresponding already existing .mmu.exit_mmap()).
As the first parameter of the old callbacks isn't used, drop it from the
replacement one.
[ bp: Remove last occurrence of paravirt_activate_mm() in
asm/mmu_context.h ]
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Link: https://lore.kernel.org/r/20230207075902.7539-1-jgross@suse.com
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Correct old function name error_exit() in the comment to what it is now
called: error_return().
[ bp: Provide a commit message and massage. ]
Signed-off-by: Jingyu Wang <jingyuwang_vip@163.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20220618154238.27749-1-jingyuwang_vip@163.com
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 updates from Thomas Gleixner:
"A small set of updates for x86:
- Return -EIO instead of success when the certificate buffer for SEV
guests is not large enough
- Allow STIPB to be enabled with legacy IBSR. Legacy IBRS is cleared
on return to userspace for performance reasons, but the leaves user
space vulnerable to cross-thread attacks which STIBP prevents.
Update the documentation accordingly"
* tag 'x86-urgent-2023-03-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
virt/sev-guest: Return -EIO if certificate buffer is not large enough
Documentation/hw-vuln: Document the interaction between IBRS and STIBP
x86/speculation: Allow enabling STIBP with legacy IBRS
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git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"17 hotfixes.
Eight are for MM and seven are for other parts of the kernel. Seven
are cc:stable and eight address post-6.3 issues or were judged
unsuitable for -stable backporting"
* tag 'mm-hotfixes-stable-2023-03-04-13-12' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mailmap: map Dikshita Agarwal's old address to his current one
mailmap: map Vikash Garodia's old address to his current one
fs/cramfs/inode.c: initialize file_ra_state
fs: hfsplus: fix UAF issue in hfsplus_put_super
panic: fix the panic_print NMI backtrace setting
lib: parser: update documentation for match_NUMBER functions
kasan, x86: don't rename memintrinsics in uninstrumented files
kasan: test: fix test for new meminstrinsic instrumentation
kasan: treat meminstrinsic as builtins in uninstrumented files
kasan: emit different calls for instrumentable memintrinsics
ocfs2: fix non-auto defrag path not working issue
ocfs2: fix defrag path triggering jbd2 ASSERT
mailmap: map Georgi Djakov's old Linaro address to his current one
mm/hwpoison: convert TTU_IGNORE_HWPOISON to TTU_HWPOISON
lib/zlib: DFLTCC deflate does not write all available bits for Z_NO_FLUSH
mm/damon/paddr: fix missing folio_put()
mm/mremap: fix dup_anon_vma() in vma_merge() case 4
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Now that memcpy/memset/memmove are no longer overridden by KASAN, we can
just use the normal symbol names in uninstrumented files.
Drop the preprocessor redefinitions.
Link: https://lkml.kernel.org/r/20230224085942.1791837-4-elver@google.com
Fixes: 69d4c0d32186 ("entry, kasan, x86: Disallow overriding mem*() functions")
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linux Kernel Functional Testing <lkft@linaro.org>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Ingo Molnar:
- Shrink 'struct instruction', to improve objtool performance & memory
footprint
- Other maximum memory usage reductions - this makes the build both
faster, and fixes kernel build OOM failures on allyesconfig and
similar configs when they try to build the final (large) vmlinux.o
- Fix ORC unwinding when a kprobe (INT3) is set on a stack-modifying
single-byte instruction (PUSH/POP or LEAVE). This requires the
extension of the ORC metadata structure with a 'signal' field
- Misc fixes & cleanups
* tag 'objtool-core-2023-03-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
objtool: Fix ORC 'signal' propagation
objtool: Remove instruction::list
x86: Fix FILL_RETURN_BUFFER
objtool: Fix overlapping alternatives
objtool: Union instruction::{call_dest,jump_table}
objtool: Remove instruction::reloc
objtool: Shrink instruction::{type,visited}
objtool: Make instruction::alts a single-linked list
objtool: Make instruction::stack_ops a single-linked list
objtool: Change arch_decode_instruction() signature
x86/entry: Fix unwinding from kprobe on PUSH/POP instruction
x86/unwind/orc: Add 'signal' field to ORC metadata
objtool: Optimize layout of struct special_alt
objtool: Optimize layout of struct symbol
objtool: Allocate multiple structures with calloc()
objtool: Make struct check_options static
objtool: Make struct entries[] static and const
objtool: Fix HOSTCC flag usage
objtool: Properly support make V=1
objtool: Install libsubcmd in build
...
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