| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
U64_MAX
Currently hv_read_tsc_page_tsc() (ab)uses the (valid) time value of
U64_MAX as an error return. This breaks the clean wrap-around of the
clock.
Modify the function signature to return a boolean state and provide
another u64 pointer to store the actual time on success. This obviates
the need to steal one time value and restores the full counter width.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Michael Kelley <mikelley@microsoft.com> # Hyper-V
Link: https://lore.kernel.org/r/20230519102715.775630881@infradead.org
|
|
Because of how the virtual clocks use U64_MAX as an exception value
instead of a valid time, the clocks can no longer be assumed to wrap
cleanly. This is then compounded by arch_vdso_cycles_ok() rejecting
everything with the MSB/Sign-bit set.
Therefore, the effective mask becomes S64_MAX, and the comment with
vdso_calc_delta() that states the mask is U64_MAX and isn't optimized
out is just plain silly.
Now, the code has a negative filter -- to deal with TSC wobbles:
if (cycles > last)
which is just plain wrong, because it should've been written as:
if ((s64)(cycles - last) > 0)
to take wrapping into account, but per all the above, we don't
actually wrap on u64 anymore.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kelley <mikelley@microsoft.com> # Hyper-V
Link: https://lore.kernel.org/r/20230519102715.704767397@infradead.org
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
- Introduce local{,64}_try_cmpxchg() - a slightly more optimal
primitive, which will be used in perf events ring-buffer code
- Simplify/modify rwsems on PREEMPT_RT, to address writer starvation
- Misc cleanups/fixes
* tag 'locking-core-2023-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/atomic: Correct (cmp)xchg() instrumentation
locking/x86: Define arch_try_cmpxchg_local()
locking/arch: Wire up local_try_cmpxchg()
locking/generic: Wire up local{,64}_try_cmpxchg()
locking/atomic: Add generic try_cmpxchg{,64}_local() support
locking/rwbase: Mitigate indefinite writer starvation
locking/arch: Rename all internal __xchg() names to __arch_xchg()
|
|
Dave Hansen found the "(long) addr >= 0" code in the x86-64 access_ok
checks somewhat confusing, and suggested using a helper to clarify what
the code is doing.
So this does exactly that: clarifying what the sign bit check is all
about, by adding a helper macro that makes it clear what it is testing.
This also adds some explicit comments talking about how even with LAM
enabled, any addresses with the sign bit will still GP-fault in the
non-canonical region just above the sign bit.
This is all what allows us to do the user address checks with just the
sign bit, and furthermore be a bit cavalier about accesses that might be
done with an additional offset even past that point.
(And yes, this talks about 'positive' even though zero is also a valid
user address and so technically we should call them 'non-negative'. But
I don't think using 'non-negative' ends up being more understandable).
Suggested-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
The intent of the sign games was to not modify kernel addresses when
untagging them. However, that had two issues:
(a) it didn't actually work as intended, since the mask was calculated
as 'addr >> 63' on an _unsigned_ address. So instead of getting a
mask of all ones for kernel addresses, you just got '1'.
(b) untagging a kernel address isn't actually a valid operation anyway.
Now, (a) had originally been true for both 'untagged_addr()' and the
remote version of it, but had accidentally been fixed for the regular
version of untagged_addr() by commit e0bddc19ba95 ("x86/mm: Reduce
untagged_addr() overhead for systems without LAM"). That one rewrote
the shift to be part of the alternative asm code, and in the process
changed the unsigned shift into a signed 'sar' instruction.
And while it is true that we don't want to turn what looks like a kernel
address into a user address by masking off the high bit, that doesn't
need these sign masking games - all it needs is that the mm context
'untag_mask' value has the high bit set.
Which it always does.
So simplify the code by just removing the superfluous (and in the case
of untagged_addr_remote(), still buggy) sign bit games in the address
masking.
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
The x86 <asm/uaccess.h> file has grown features that are specific to
x86-64 like LAM support and the related access_ok() changes. They
really should be in the <asm/uaccess_64.h> file and not pollute the
generic x86 header.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
There's already a generic definition of 'access_ok()' in the
asm-generic/access_ok.h header file, and the only difference bwteen that
and the x86-specific one is the added check for WARN_ON_IN_IRQ().
And it turns out that the reason for that check is long gone: it used to
use a "user_addr_max()" inline function that depended on the current
thread, and caused problems in non-thread contexts.
For details, see commits 7c4788950ba5 ("x86/uaccess, sched/preempt:
Verify access_ok() context") and in particular commit ae31fe51a3cc
("perf/x86: Restore TASK_SIZE check on frame pointer") about how and why
this came to be.
But that "current task" issue was removed in the big set_fs() removal by
Christoph Hellwig in commit 47058bb54b57 ("x86: remove address space
overrides using set_fs()").
So the reason for the test and the architecture-specific access_ok()
define no longer exists, and is actually harmful these days. For
example, it led various 'copy_from_user_nmi()' games (eg using
__range_not_ok() instead, and then later converted to __access_ok() when
that became ok).
And that in turn meant that LAM was broken for the frame following
before this series, because __access_ok() used to not do the address
untagging.
Accessing user state still needs care in many contexts, but access_ok()
is not the place for this test.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Linus Torvalds torvalds@linux-foundation.org>
|
|
The linear address masking (LAM) code made access_ok() more complicated,
in that it now needs to untag the address in order to verify the access
range. See commit 74c228d20a51 ("x86/uaccess: Provide untagged_addr()
and remove tags before address check").
We were able to avoid that overhead in the get_user/put_user code paths
by simply using the sign bit for the address check, and depending on the
GP fault if the address was non-canonical, which made it all independent
of LAM.
And we can do the same thing for access_ok(): simply check that the user
pointer range has the high bit clear. No need to bother with any
address bit masking.
In fact, we can go a bit further, and just check the starting address
for known small accesses ranges: any accesses that overflow will still
be in the non-canonical area and will still GP fault.
To still make syzkaller catch any potentially unchecked user addresses,
we'll continue to warn about GP faults that are caused by accesses in
the non-canonical range. But we'll limit that to purely "high bit set
and past the one-page 'slop' area".
We could probably just do that "check only starting address" for any
arbitrary range size: realistically all kernel accesses to user space
will be done starting at the low address. But let's leave that kind of
optimization for later. As it is, this already allows us to generate
simpler code and not worry about any tag bits in the address.
The one thing to look out for is the GUP address check: instead of
actually copying data in the virtual address range (and thus bad
addresses being caught by the GP fault), GUP will look up the page
tables manually. As a result, the page table limits need to be checked,
and that was previously implicitly done by the access_ok().
With the relaxed access_ok() check, we need to just do an explicit check
for TASK_SIZE_MAX in the GUP code instead. The GUP code already needs
to do the tag bit unmasking anyway, so there this is all very
straightforward, and there are no LAM issues.
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Pull kvm updates from Paolo Bonzini:
"s390:
- More phys_to_virt conversions
- Improvement of AP management for VSIE (nested virtualization)
ARM64:
- Numerous fixes for the pathological lock inversion issue that
plagued KVM/arm64 since... forever.
- New framework allowing SMCCC-compliant hypercalls to be forwarded
to userspace, hopefully paving the way for some more features being
moved to VMMs rather than be implemented in the kernel.
- Large rework of the timer code to allow a VM-wide offset to be
applied to both virtual and physical counters as well as a
per-timer, per-vcpu offset that complements the global one. This
last part allows the NV timer code to be implemented on top.
- A small set of fixes to make sure that we don't change anything
affecting the EL1&0 translation regime just after having having
taken an exception to EL2 until we have executed a DSB. This
ensures that speculative walks started in EL1&0 have completed.
- The usual selftest fixes and improvements.
x86:
- Optimize CR0.WP toggling by avoiding an MMU reload when TDP is
enabled, and by giving the guest control of CR0.WP when EPT is
enabled on VMX (VMX-only because SVM doesn't support per-bit
controls)
- Add CR0/CR4 helpers to query single bits, and clean up related code
where KVM was interpreting kvm_read_cr4_bits()'s "unsigned long"
return as a bool
- Move AMD_PSFD to cpufeatures.h and purge KVM's definition
- Avoid unnecessary writes+flushes when the guest is only adding new
PTEs
- Overhaul .sync_page() and .invlpg() to utilize .sync_page()'s
optimizations when emulating invalidations
- Clean up the range-based flushing APIs
- Revamp the TDP MMU's reaping of Accessed/Dirty bits to clear a
single A/D bit using a LOCK AND instead of XCHG, and skip all of
the "handle changed SPTE" overhead associated with writing the
entire entry
- Track the number of "tail" entries in a pte_list_desc to avoid
having to walk (potentially) all descriptors during insertion and
deletion, which gets quite expensive if the guest is spamming
fork()
- Disallow virtualizing legacy LBRs if architectural LBRs are
available, the two are mutually exclusive in hardware
- Disallow writes to immutable feature MSRs (notably
PERF_CAPABILITIES) after KVM_RUN, similar to CPUID features
- Overhaul the vmx_pmu_caps selftest to better validate
PERF_CAPABILITIES
- Apply PMU filters to emulated events and add test coverage to the
pmu_event_filter selftest
- AMD SVM:
- Add support for virtual NMIs
- Fixes for edge cases related to virtual interrupts
- Intel AMX:
- Don't advertise XTILE_CFG in KVM_GET_SUPPORTED_CPUID if
XTILE_DATA is not being reported due to userspace not opting in
via prctl()
- Fix a bug in emulation of ENCLS in compatibility mode
- Allow emulation of NOP and PAUSE for L2
- AMX selftests improvements
- Misc cleanups
MIPS:
- Constify MIPS's internal callbacks (a leftover from the hardware
enabling rework that landed in 6.3)
Generic:
- Drop unnecessary casts from "void *" throughout kvm_main.c
- Tweak the layout of "struct kvm_mmu_memory_cache" to shrink the
struct size by 8 bytes on 64-bit kernels by utilizing a padding
hole
Documentation:
- Fix goof introduced by the conversion to rST"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (211 commits)
KVM: s390: pci: fix virtual-physical confusion on module unload/load
KVM: s390: vsie: clarifications on setting the APCB
KVM: s390: interrupt: fix virtual-physical confusion for next alert GISA
KVM: arm64: Have kvm_psci_vcpu_on() use WRITE_ONCE() to update mp_state
KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init()
KVM: selftests: Test the PMU event "Instructions retired"
KVM: selftests: Copy full counter values from guest in PMU event filter test
KVM: selftests: Use error codes to signal errors in PMU event filter test
KVM: selftests: Print detailed info in PMU event filter asserts
KVM: selftests: Add helpers for PMC asserts in PMU event filter test
KVM: selftests: Add a common helper for the PMU event filter guest code
KVM: selftests: Fix spelling mistake "perrmited" -> "permitted"
KVM: arm64: vhe: Drop extra isb() on guest exit
KVM: arm64: vhe: Synchronise with page table walker on MMU update
KVM: arm64: pkvm: Document the side effects of kvm_flush_dcache_to_poc()
KVM: arm64: nvhe: Synchronise with page table walker on TLBI
KVM: arm64: Handle 32bit CNTPCTSS traps
KVM: arm64: nvhe: Synchronise with page table walker on vcpu run
KVM: arm64: vgic: Don't acquire its_lock before config_lock
KVM: selftests: Add test to verify KVM's supported XCR0
...
|
|
Define target specific arch_try_cmpxchg_local(). This
definition overrides the generic arch_try_cmpxchg_local()
fallback definition and enables target-specific
implementation of try_cmpxchg_local().
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230405141710.3551-5-ubizjak@gmail.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Implement target specific support for local_try_cmpxchg()
and local_cmpxchg() using typed C wrappers that call their
_local counterpart and provide additional checking of
their input arguments.
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230405141710.3551-4-ubizjak@gmail.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull SMP cross-CPU function-call updates from Ingo Molnar:
- Remove diagnostics and adjust config for CSD lock diagnostics
- Add a generic IPI-sending tracepoint, as currently there's no easy
way to instrument IPI origins: it's arch dependent and for some major
architectures it's not even consistently available.
* tag 'smp-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
trace,smp: Trace all smp_function_call*() invocations
trace: Add trace_ipi_send_cpu()
sched, smp: Trace smp callback causing an IPI
smp: reword smp call IPI comment
treewide: Trace IPIs sent via smp_send_reschedule()
irq_work: Trace self-IPIs sent via arch_irq_work_raise()
smp: Trace IPIs sent via arch_send_call_function_ipi_mask()
sched, smp: Trace IPIs sent via send_call_function_single_ipi()
trace: Add trace_ipi_send_cpumask()
kernel/smp: Make csdlock_debug= resettable
locking/csd_lock: Remove per-CPU data indirection from CSD lock debugging
locking/csd_lock: Remove added data from CSD lock debugging
locking/csd_lock: Add Kconfig option for csd_debug default
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Ingo Molnar:
- Mark arch_cpu_idle_dead() __noreturn, make all architectures &
drivers that did this inconsistently follow this new, common
convention, and fix all the fallout that objtool can now detect
statically
- Fix/improve the ORC unwinder becoming unreliable due to
UNWIND_HINT_EMPTY ambiguity, split it into UNWIND_HINT_END_OF_STACK
and UNWIND_HINT_UNDEFINED to resolve it
- Fix noinstr violations in the KCSAN code and the lkdtm/stackleak code
- Generate ORC data for __pfx code
- Add more __noreturn annotations to various kernel startup/shutdown
and panic functions
- Misc improvements & fixes
* tag 'objtool-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
x86/hyperv: Mark hv_ghcb_terminate() as noreturn
scsi: message: fusion: Mark mpt_halt_firmware() __noreturn
x86/cpu: Mark {hlt,resume}_play_dead() __noreturn
btrfs: Mark btrfs_assertfail() __noreturn
objtool: Include weak functions in global_noreturns check
cpu: Mark nmi_panic_self_stop() __noreturn
cpu: Mark panic_smp_self_stop() __noreturn
arm64/cpu: Mark cpu_park_loop() and friends __noreturn
x86/head: Mark *_start_kernel() __noreturn
init: Mark start_kernel() __noreturn
init: Mark [arch_call_]rest_init() __noreturn
objtool: Generate ORC data for __pfx code
x86/linkage: Fix padding for typed functions
objtool: Separate prefix code from stack validation code
objtool: Remove superfluous dead_end_function() check
objtool: Add symbol iteration helpers
objtool: Add WARN_INSN()
scripts/objdump-func: Support multiple functions
context_tracking: Fix KCSAN noinstr violation
objtool: Add stackleak instrumentation to uaccess safe list
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 LAM (Linear Address Masking) support from Dave Hansen:
"Add support for the new Linear Address Masking CPU feature.
This is similar to ARM's Top Byte Ignore and allows userspace to store
metadata in some bits of pointers without masking it out before use"
* tag 'x86_mm_for_6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm/iommu/sva: Do not allow to set FORCE_TAGGED_SVA bit from outside
x86/mm/iommu/sva: Fix error code for LAM enabling failure due to SVA
selftests/x86/lam: Add test cases for LAM vs thread creation
selftests/x86/lam: Add ARCH_FORCE_TAGGED_SVA test cases for linear-address masking
selftests/x86/lam: Add inherit test cases for linear-address masking
selftests/x86/lam: Add io_uring test cases for linear-address masking
selftests/x86/lam: Add mmap and SYSCALL test cases for linear-address masking
selftests/x86/lam: Add malloc and tag-bits test cases for linear-address masking
x86/mm/iommu/sva: Make LAM and SVA mutually exclusive
iommu/sva: Replace pasid_valid() helper with mm_valid_pasid()
mm: Expose untagging mask in /proc/$PID/status
x86/mm: Provide arch_prctl() interface for LAM
x86/mm: Reduce untagged_addr() overhead for systems without LAM
x86/uaccess: Provide untagged_addr() and remove tags before address check
mm: Introduce untagged_addr_remote()
x86/mm: Handle LAM on context switch
x86: CPUID and CR3/CR4 flags for Linear Address Masking
x86: Allow atomic MM_CONTEXT flags setting
x86/mm: Rework address range check in get_user() and put_user()
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 tdx update from Dave Hansen:
"The original tdx hypercall assembly code took two flags in %RSI to
tweak its behavior at runtime. PeterZ recently axed one flag in commit
e80a48bade61 ("x86/tdx: Remove TDX_HCALL_ISSUE_STI").
Kill the other flag too and tweak the 'output' mode with an assembly
macro instead. This results in elimination of one push/pop pair and
overall easier to read assembly.
- Do conditional __tdx_hypercall() 'output' processing via an
assembly macro argument rather than a runtime register"
* tag 'x86_tdx_for_6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tdx: Drop flags from __tdx_hypercall()
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cleanups from Borislav Petkov:
- Unify duplicated __pa() and __va() definitions
- Simplify sysctl tables registration
- Remove unused symbols
- Correct function name in comment
* tag 'x86_cleanups_for_v6.4_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot: Centralize __pa()/__va() definitions
x86: Simplify one-level sysctl registration for itmt_kern_table
x86: Simplify one-level sysctl registration for abi_table2
x86/platform/intel-mid: Remove unused definitions from intel-mid.h
x86/uaccess: Remove memcpy_page_flushcache()
x86/entry: Change stale function name in comment to error_return()
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
"Mainly singleton patches all over the place.
Series of note are:
- updates to scripts/gdb from Glenn Washburn
- kexec cleanups from Bjorn Helgaas"
* tag 'mm-nonmm-stable-2023-04-27-16-01' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (50 commits)
mailmap: add entries for Paul Mackerras
libgcc: add forward declarations for generic library routines
mailmap: add entry for Oleksandr
ocfs2: reduce ioctl stack usage
fs/proc: add Kthread flag to /proc/$pid/status
ia64: fix an addr to taddr in huge_pte_offset()
checkpatch: introduce proper bindings license check
epoll: rename global epmutex
scripts/gdb: add GDB convenience functions $lx_dentry_name() and $lx_i_dentry()
scripts/gdb: create linux/vfs.py for VFS related GDB helpers
uapi/linux/const.h: prefer ISO-friendly __typeof__
delayacct: track delays from IRQ/SOFTIRQ
scripts/gdb: timerlist: convert int chunks to str
scripts/gdb: print interrupts
scripts/gdb: raise error with reduced debugging information
scripts/gdb: add a Radix Tree Parser
lib/rbtree: use '+' instead of '|' for setting color.
proc/stat: remove arch_idle_time()
checkpatch: check for misuse of the link tags
checkpatch: allow Closes tags with links
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
- Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of
switching from a user process to a kernel thread.
- More folio conversions from Kefeng Wang, Zhang Peng and Pankaj
Raghav.
- zsmalloc performance improvements from Sergey Senozhatsky.
- Yue Zhao has found and fixed some data race issues around the
alteration of memcg userspace tunables.
- VFS rationalizations from Christoph Hellwig:
- removal of most of the callers of write_one_page()
- make __filemap_get_folio()'s return value more useful
- Luis Chamberlain has changed tmpfs so it no longer requires swap
backing. Use `mount -o noswap'.
- Qi Zheng has made the slab shrinkers operate locklessly, providing
some scalability benefits.
- Keith Busch has improved dmapool's performance, making part of its
operations O(1) rather than O(n).
- Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd,
permitting userspace to wr-protect anon memory unpopulated ptes.
- Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive
rather than exclusive, and has fixed a bunch of errors which were
caused by its unintuitive meaning.
- Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature,
which causes minor faults to install a write-protected pte.
- Vlastimil Babka has done some maintenance work on vma_merge():
cleanups to the kernel code and improvements to our userspace test
harness.
- Cleanups to do_fault_around() by Lorenzo Stoakes.
- Mike Rapoport has moved a lot of initialization code out of various
mm/ files and into mm/mm_init.c.
- Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for
DRM, but DRM doesn't use it any more.
- Lorenzo has also coverted read_kcore() and vread() to use iterators
and has thereby removed the use of bounce buffers in some cases.
- Lorenzo has also contributed further cleanups of vma_merge().
- Chaitanya Prakash provides some fixes to the mmap selftesting code.
- Matthew Wilcox changes xfs and afs so they no longer take sleeping
locks in ->map_page(), a step towards RCUification of pagefaults.
- Suren Baghdasaryan has improved mmap_lock scalability by switching to
per-VMA locking.
- Frederic Weisbecker has reworked the percpu cache draining so that it
no longer causes latency glitches on cpu isolated workloads.
- Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig
logic.
- Liu Shixin has changed zswap's initialization so we no longer waste a
chunk of memory if zswap is not being used.
- Yosry Ahmed has improved the performance of memcg statistics
flushing.
- David Stevens has fixed several issues involving khugepaged,
userfaultfd and shmem.
- Christoph Hellwig has provided some cleanup work to zram's IO-related
code paths.
- David Hildenbrand has fixed up some issues in the selftest code's
testing of our pte state changing.
- Pankaj Raghav has made page_endio() unneeded and has removed it.
- Peter Xu contributed some rationalizations of the userfaultfd
selftests.
- Yosry Ahmed has fixed an issue around memcg's page recalim
accounting.
- Chaitanya Prakash has fixed some arm-related issues in the
selftests/mm code.
- Longlong Xia has improved the way in which KSM handles hwpoisoned
pages.
- Peter Xu fixes a few issues with uffd-wp at fork() time.
- Stefan Roesch has changed KSM so that it may now be used on a
per-process and per-cgroup basis.
* tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
mm,unmap: avoid flushing TLB in batch if PTE is inaccessible
shmem: restrict noswap option to initial user namespace
mm/khugepaged: fix conflicting mods to collapse_file()
sparse: remove unnecessary 0 values from rc
mm: move 'mmap_min_addr' logic from callers into vm_unmapped_area()
hugetlb: pte_alloc_huge() to replace huge pte_alloc_map()
maple_tree: fix allocation in mas_sparse_area()
mm: do not increment pgfault stats when page fault handler retries
zsmalloc: allow only one active pool compaction context
selftests/mm: add new selftests for KSM
mm: add new KSM process and sysfs knobs
mm: add new api to enable ksm per process
mm: shrinkers: fix debugfs file permissions
mm: don't check VMA write permissions if the PTE/PMD indicates write permissions
migrate_pages_batch: fix statistics for longterm pin retry
userfaultfd: use helper function range_in_vma()
lib/show_mem.c: use for_each_populated_zone() simplify code
mm: correct arg in reclaim_pages()/reclaim_clean_pages_from_list()
fs/buffer: convert create_page_buffers to folio_create_buffers
fs/buffer: add folio_create_empty_buffers helper
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux
Pull hyperv updates from Wei Liu:
- PCI passthrough for Hyper-V confidential VMs (Michael Kelley)
- Hyper-V VTL mode support (Saurabh Sengar)
- Move panic report initialization code earlier (Long Li)
- Various improvements and bug fixes (Dexuan Cui and Michael Kelley)
* tag 'hyperv-next-signed-20230424' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: (22 commits)
PCI: hv: Replace retarget_msi_interrupt_params with hyperv_pcpu_input_arg
Drivers: hv: move panic report code from vmbus to hv early init code
x86/hyperv: VTL support for Hyper-V
Drivers: hv: Kconfig: Add HYPERV_VTL_MODE
x86/hyperv: Make hv_get_nmi_reason public
x86/hyperv: Add VTL specific structs and hypercalls
x86/init: Make get/set_rtc_noop() public
x86/hyperv: Exclude lazy TLB mode CPUs from enlightened TLB flushes
x86/hyperv: Add callback filter to cpumask_to_vpset()
Drivers: hv: vmbus: Remove the per-CPU post_msg_page
clocksource: hyper-v: make sure Invariant-TSC is used if it is available
PCI: hv: Enable PCI pass-thru devices in Confidential VMs
Drivers: hv: Don't remap addresses that are above shared_gpa_boundary
hv_netvsc: Remove second mapping of send and recv buffers
Drivers: hv: vmbus: Remove second way of mapping ring buffers
Drivers: hv: vmbus: Remove second mapping of VMBus monitor pages
swiotlb: Remove bounce buffer remapping for Hyper-V
Driver: VMBus: Add Devicetree support
dt-bindings: bus: Add Hyper-V VMBus
Drivers: hv: vmbus: Convert acpi_device to more generic platform_device
...
|
|
KVM SVM changes for 6.4:
- Add support for virtual NMIs
- Fixes for edge cases related to virtual interrupts
|
|
KVM x86 PMU changes for 6.4:
- Disallow virtualizing legacy LBRs if architectural LBRs are available,
the two are mutually exclusive in hardware
- Disallow writes to immutable feature MSRs (notably PERF_CAPABILITIES)
after KVM_RUN, and overhaul the vmx_pmu_caps selftest to better
validate PERF_CAPABILITIES
- Apply PMU filters to emulated events and add test coverage to the
pmu_event_filter selftest
- Misc cleanups and fixes
|
|
KVM x86 MMU changes for 6.4:
- Tweak FNAME(sync_spte) to avoid unnecessary writes+flushes when the
guest is only adding new PTEs
- Overhaul .sync_page() and .invlpg() to share the .sync_page()
implementation, i.e. utilize .sync_page()'s optimizations when emulating
invalidations
- Clean up the range-based flushing APIs
- Revamp the TDP MMU's reaping of Accessed/Dirty bits to clear a single
A/D bit using a LOCK AND instead of XCHG, and skip all of the "handle
changed SPTE" overhead associated with writing the entire entry
- Track the number of "tail" entries in a pte_list_desc to avoid having
to walk (potentially) all descriptors during insertion and deletion,
which gets quite expensive if the guest is spamming fork()
- Misc cleanups
|
|
KVM x86 changes for 6.4:
- Optimize CR0.WP toggling by avoiding an MMU reload when TDP is enabled,
and by giving the guest control of CR0.WP when EPT is enabled on VMX
(VMX-only because SVM doesn't support per-bit controls)
- Add CR0/CR4 helpers to query single bits, and clean up related code
where KVM was interpreting kvm_read_cr4_bits()'s "unsigned long" return
as a bool
- Move AMD_PSFD to cpufeatures.h and purge KVM's definition
- Misc cleanups
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64 updates for 6.4
- Numerous fixes for the pathological lock inversion issue that
plagued KVM/arm64 since... forever.
- New framework allowing SMCCC-compliant hypercalls to be forwarded
to userspace, hopefully paving the way for some more features
being moved to VMMs rather than be implemented in the kernel.
- Large rework of the timer code to allow a VM-wide offset to be
applied to both virtual and physical counters as well as a
per-timer, per-vcpu offset that complements the global one.
This last part allows the NV timer code to be implemented on
top.
- A small set of fixes to make sure that we don't change anything
affecting the EL1&0 translation regime just after having having
taken an exception to EL2 until we have executed a DSB. This
ensures that speculative walks started in EL1&0 have completed.
- The usual selftest fixes and improvements.
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86
Pull x86 platform driver updates from Hans de Goede:
- AMD PMC and PMF drivers:
- Numerous bugfixes
- Intel Speed Select Technology (ISST):
- TPMI (Topology Aware Register and PM Capsule Interface) support
for ISST support on upcoming processor models
- Various other improvements / new hw support
- tools/intel-speed-select: TPMI support + other improvements
- Intel In Field Scan (IFS):
- Add Array Bist test support
- New drivers:
- intel_bytcrc_pwrsrc Crystal Cove PMIC pwrsrc / reset-reason driver
- lenovo-ymc Yoga Mode Control driver for reporting SW_TABLET_MODE
- msi-ec Driver for MSI laptop EC features like battery charging limits
- apple-gmux:
- Support for new MMIO based models (T2 Macs)
- Honor acpi_backlight= auto-detect-code + kernel cmdline option
to switch between gmux and apple_bl backlight drivers and remove
own custom handling for this
- x86-android-tablets: Refactor / cleanup + new hw support
- Miscellaneous other cleanups / fixes
* tag 'platform-drivers-x86-v6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: (178 commits)
platform/x86: x86-android-tablets: Add accelerometer support for Yoga Tablet 2 1050/830 series
platform/x86: x86-android-tablets: Add "yogabook-touch-kbd-digitizer-switch" pdev for Lenovo Yoga Book
platform/x86: x86-android-tablets: Add Wacom digitizer info for Lenovo Yoga Book
platform/x86: x86-android-tablets: Update Yoga Book HiDeep touchscreen comment
platform/x86: thinkpad_acpi: Fix Embedded Controller access on X380 Yoga
platform/x86/intel/sdsi: Change mailbox timeout
platform/x86/intel/pmt: Ignore uninitialized entries
platform/x86: amd: pmc: provide user message where s0ix is not supported
platform/x86/amd: pmc: Fix memory leak in amd_pmc_stb_debugfs_open_v2()
mlxbf-bootctl: Add sysfs file for BlueField boot fifo
platform/x86: amd: pmc: Remove __maybe_unused from amd_pmc_suspend_handler()
platform/x86/intel/pmc/mtl: Put GNA/IPU/VPU devices in D3
platform/x86/amd: pmc: Move out of BIOS SMN pair for STB init
platform/x86/amd: pmc: Utilize SMN index 0 for driver probe
platform/x86/amd: pmc: Move idlemask check into `amd_pmc_idlemask_read`
platform/x86/amd: pmc: Don't dump data after resume from s0i3 on picasso
platform/x86/amd: pmc: Hide SMU version and program attributes for Picasso
platform/x86/amd: pmc: Don't try to read SMU version on Picasso
platform/x86/amd/pmf: Move out of BIOS SMN pair for driver probe
platform/x86: intel-uncore-freq: Add client processors
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 APIC updates from Thomas Gleixner:
- Fix the incorrect handling of atomic offset updates in
reserve_eilvt_offset()
The check for the return value of atomic_cmpxchg() is not compared
against the old value, it is compared against the new value, which
makes it two round on success.
Convert it to atomic_try_cmpxchg() which does the right thing.
- Handle IO/APIC less systems correctly
When IO/APIC is not advertised by ACPI then the computation of the
lower bound for dynamically allocated interrupts like MSI goes wrong.
This lower bound is used to exclude the IO/APIC legacy GSI space as
that must stay reserved for the legacy interrupts.
In case that the system, e.g. VM, does not advertise an IO/APIC the
lower bound stays at 0.
0 is an invalid interrupt number except for the legacy timer
interrupt on x86. The return value is unchecked in the core code, so
it ends up to allocate interrupt number 0 which is subsequently
considered to be invalid by the caller, e.g. the MSI allocation code.
A similar problem was already cured for device tree based systems
years ago, but that missed - or did not envision - the zero IO/APIC
case.
Consolidate the zero check and return the provided "from" argument to
the core code call site, which is guaranteed to be greater than 0.
- Simplify the X2APIC cluster CPU mask logic for CPU hotplug
Per cluster CPU masks are required for X2APIC in cluster mode to
determine the correct cluster for a target CPU when calculating the
destination for IPIs
These masks are established when CPUs are borught up. The first CPU
in a cluster must allocate a new cluster CPU mask. As this happens
during the early startup of a CPU, where memory allocations cannot be
done, the mask has to be allocated by the control CPU.
The current implementation allocates a clustermask just in case and
if the to be brought up CPU is the first in a cluster the CPU takes
over this allocation from a global pointer.
This works nicely in the fully serialized CPU bringup scenario which
is used today, but would fail completely for parallel bringup of
CPUs.
The cluster association of a CPU can be computed from the APIC ID
which is enumerated by ACPI/MADT.
So the cluster CPU masks can be preallocated and associated upfront
and the upcoming CPUs just need to set their corresponding bit.
Aside of preparing for parallel bringup this is a valuable
simplification on its own.
- Remove global variables which control the early startup of secondary
CPUs on 64-bit
The only information which is needed by a starting CPU is the Linux
CPU number. The CPU number allows it to retrieve the rest of the
required data from already existing per CPU storage.
So instead of initial_stack, early_gdt_desciptor and initial_gs
provide a new variable smpboot_control which contains the Linux CPU
number for now. The starting CPU can retrieve and compute all
required information for startup from there.
Aside of being a cleanup, this is also preparing for parallel CPU
bringup, where starting CPUs will look up their Linux CPU number via
the APIC ID, when smpboot_control has the corresponding control bit
set.
- Make cc_vendor globally accesible
Subsequent parallel bringup changes require access to cc_vendor
because confidental computing platforms need special treatment in the
early startup phase vs. CPUID and APCI ID readouts.
The change makes cc_vendor global and provides stub accessors in case
that CONFIG_ARCH_HAS_CC_PLATFORM is not set.
This was merged from the x86/cc branch in anticipation of further
parallel bringup commits which require access to cc_vendor. Due to
late discoveries of fundamental issue with those patches these
commits never happened.
The merge commit is unfortunately in the middle of the APIC commits
so unraveling it would have required a rebase or revert. As the
parallel bringup seems to be well on its way for 6.5 this would be
just pointless churn. As the commit does not contain any functional
change it's not a risk to keep it.
* tag 'x86-apic-2023-04-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/ioapic: Don't return 0 from arch_dynirq_lower_bound()
x86/apic: Fix atomic update of offset in reserve_eilvt_offset()
x86/coco: Export cc_vendor
x86/smpboot: Reference count on smpboot_setup_warm_reset_vector()
x86/smpboot: Remove initial_gs
x86/smpboot: Remove early_gdt_descr on 64-bit
x86/smpboot: Remove initial_stack on 64-bit
x86/apic/x2apic: Allow CPU cluster_mask to be populated in parallel
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 SEV updates from Borislav Petkov:
- Add the necessary glue so that the kernel can run as a confidential
SEV-SNP vTOM guest on Hyper-V. A vTOM guest basically splits the
address space in two parts: encrypted and unencrypted. The use case
being running unmodified guests on the Hyper-V confidential computing
hypervisor
- Double-buffer messages between the guest and the hardware PSP device
so that no partial buffers are copied back'n'forth and thus potential
message integrity and leak attacks are possible
- Name the return value the sev-guest driver returns when the hw PSP
device hasn't been called, explicitly
- Cleanups
* tag 'x86_sev_for_v6.4_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/hyperv: Change vTOM handling to use standard coco mechanisms
init: Call mem_encrypt_init() after Hyper-V hypercall init is done
x86/mm: Handle decryption/re-encryption of bss_decrypted consistently
Drivers: hv: Explicitly request decrypted in vmap_pfn() calls
x86/hyperv: Reorder code to facilitate future work
x86/ioremap: Add hypervisor callback for private MMIO mapping in coco VM
x86/sev: Change snp_guest_issue_request()'s fw_err argument
virt/coco/sev-guest: Double-buffer messages
crypto: ccp: Get rid of __sev_platform_init_locked()'s local function pointer
crypto: ccp - Name -1 return value as SEV_RET_NO_FW_CALL
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 paravirt updates from Borislav Petkov:
- Convert a couple of paravirt callbacks to asm to prevent
'-fzero-call-used-regs' builds from zeroing live registers because
paravirt hides the CALLs from the compiler so latter doesn't know
there's a CALL in the first place
- Merge two paravirt callbacks into one, as their functionality is
identical
* tag 'x86_paravirt_for_v6.4_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/paravirt: Convert simple paravirt functions to asm
x86/paravirt: Merge activate_mm() and dup_mmap() callbacks
|
|
Pull documentation updates from Jonathan Corbet:
"Commit volume in documentation is relatively low this time, but there
is still a fair amount going on, including:
- Reorganize the architecture-specific documentation under
Documentation/arch
This makes the structure match the source directory and helps to
clean up the mess that is the top-level Documentation directory a
bit. This work creates the new directory and moves x86 and most of
the less-active architectures there.
The current plan is to move the rest of the architectures in 6.5,
with the patches going through the appropriate subsystem trees.
- Some more Spanish translations and maintenance of the Italian
translation
- A new "Kernel contribution maturity model" document from Ted
- A new tutorial on quickly building a trimmed kernel from Thorsten
Plus the usual set of updates and fixes"
* tag 'docs-6.4' of git://git.lwn.net/linux: (47 commits)
media: Adjust column width for pdfdocs
media: Fix building pdfdocs
docs: clk: add documentation to log which clocks have been disabled
docs: trace: Fix typo in ftrace.rst
Documentation/process: always CC responsible lists
docs: kmemleak: adjust to config renaming
ELF: document some de-facto PT_* ABI quirks
Documentation: arm: remove stih415/stih416 related entries
docs: turn off "smart quotes" in the HTML build
Documentation: firmware: Clarify firmware path usage
docs/mm: Physical Memory: Fix grammar
Documentation: Add document for false sharing
dma-api-howto: typo fix
docs: move m68k architecture documentation under Documentation/arch/
docs: move parisc documentation under Documentation/arch/
docs: move ia64 architecture docs under Documentation/arch/
docs: Move arc architecture docs under Documentation/arch/
docs: move nios2 documentation under Documentation/arch/
docs: move openrisc documentation under Documentation/arch/
docs: move superh documentation under Documentation/arch/
...
|
|
Merge my x86 user copy updates branch.
This cleans up a lot of our x86 memory copy code, particularly for user
accesses. I've been pushing for microarchitectural support for good
memory copying and clearing for a long while, and it's been visible in
how the kernel has aggressively used 'rep movs' and 'rep stos' whenever
possible.
And that micro-architectural support has been improving over the years,
to the point where on modern CPU's the best option for a memory copy
that would become a function call (as opposed to being something that
can just be turned into individual 'mov' instructions) is now to inline
the string instruction sequence instead.
However, that only makes sense when we have the modern markers for this:
the x86 FSRM and FSRS capabilities ("Fast Short REP MOVS/STOS").
So this cleans up a lot of our historical code, gets rid of the legacy
marker use ("REP_GOOD" and "ERMS") from the memcpy/memset cases, and
replaces it with that modern reality. Note that REP_GOOD and ERMS end
up still being used by the known large cases (ie page copyin gand
clearing).
The reason much of this ends up being about user memory accesses is that
the normal in-kernel cases are done by the compiler (__builtin_memcpy()
and __builtin_memset()) and getting to the point where we can use our
instruction rewriting to inline those to be string instructions will
need some compiler support.
In contrast, the user accessor functions are all entirely controlled by
the kernel code, so we can change those arbitrarily.
Thanks to Borislav Petkov for feedback on the series, and Jens testing
some of this on micro-architectures I didn't personally have access to.
* x86-rep-insns:
x86: rewrite '__copy_user_nocache' function
x86: remove 'zerorest' argument from __copy_user_nocache()
x86: set FSRS automatically on AMD CPUs that have FSRM
x86: improve on the non-rep 'copy_user' function
x86: improve on the non-rep 'clear_user' function
x86: inline the 'rep movs' in user copies for the FSRM case
x86: move stac/clac from user copy routines into callers
x86: don't use REP_GOOD or ERMS for user memory clearing
x86: don't use REP_GOOD or ERMS for user memory copies
x86: don't use REP_GOOD or ERMS for small memory clearing
x86: don't use REP_GOOD or ERMS for small memory copies
|
|
Every caller passes in zero, meaning they don't want any partial copy to
zero the remainder of the destination buffer.
Which is just as well, because the implementation of that function
didn't actually even look at that argument, and wasn't even aware it
existed, although some misleading comments did mention it still.
The 'zerorest' thing is a historical artifact of how "copy_from_user()"
worked, in that it would zero the rest of the kernel buffer that it
copied into.
That zeroing still exists, but it's long since been moved to generic
code, and the raw architecture-specific code doesn't do it. See
_copy_from_user() in lib/usercopy.c for this all.
However, while __copy_user_nocache() shares some history and superficial
other similarities with copy_from_user(), it is in many ways also very
different.
In particular, while the code makes it *look* similar to the generic
user copy functions that can copy both to and from user space, and take
faults on both reads and writes as a result, __copy_user_nocache() does
no such thing at all.
__copy_user_nocache() always copies to kernel space, and will never take
a page fault on the destination. What *can* happen, though, is that the
non-temporal stores take a machine check because one of the use cases is
for writing to stable memory, and any memory errors would then take
synchronous faults.
So __copy_user_nocache() does look a lot like copy_from_user(), but has
faulting behavior that is more akin to our old copy_in_user() (which no
longer exists, but copied from user space to user space and could fault
on both source and destination).
And it very much does not have the "zero the end of the destination
buffer", since a problem with the destination buffer is very possibly
the very source of the partial copy.
So this whole thing was just a confusing historical artifact from having
shared some code with a completely different function with completely
different use cases.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
The old 'copy_user_generic_unrolled' function was oddly implemented for
largely historical reasons: it had been largely based on the uncached
copy case, which has some other concerns.
For example, the __copy_user_nocache() function uses 'movnti' for the
destination stores, and those want the destination to be aligned. In
contrast, the regular copy function doesn't really care, and trying to
align things only complicates matters.
Also, like the clear_user function, the copy function had some odd
handling of the repeat counts, complicating the exception handling for
no really good reason. So as with clear_user, just write it to keep all
the byte counts in the %rcx register, exactly like the 'rep movs'
functionality that this replaces.
Unlike a real 'rep movs', we do allow for this to trash a few temporary
registers to not have to unnecessarily save/restore registers on the
stack.
And like the clearing case, rename this to what it now clearly is:
'rep_movs_alternative', and make it one coherent function, so that it
shows up as such in profiles (instead of the odd split between
"copy_user_generic_unrolled" and "copy_user_short_string", the latter of
which was not about strings at all, and which was shared with the
uncached case).
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
The old version was oddly written to have the repeat count in multiple
registers. So instead of taking advantage of %rax being zero, it had
some sub-counts in it. All just for a "single word clearing" loop,
which isn't even efficient to begin with.
So get rid of those games, and just keep all the state in the same
registers we got it in (and that we should return things in). That not
only makes this act much more like 'rep stos' (which this function is
replacing), but makes it much easier to actually do the obvious loop
unrolling.
Also rename the function from the now nonsensical 'clear_user_original'
to what it now clearly is: 'rep_stos_alternative'.
End result: if we don't have a fast 'rep stosb', at least we can have a
fast fallback for it.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
This does the same thing for the user copies as commit 0db7058e8e23
("x86/clear_user: Make it faster") did for clear_user(). In other
words, it inlines the "rep movs" case when X86_FEATURE_FSRM is set,
avoiding the function call entirely.
In order to do that, it makes the calling convention for the out-of-line
case ("copy_user_generic_unrolled") match the 'rep movs' calling
convention, although it does also end up clobbering a number of
additional registers.
Also, to simplify code sharing in the low-level assembly with the
__copy_user_nocache() function (that uses the normal C calling
convention), we end up with a kind of mixed return value for the
low-level asm code: it will return the result in both %rcx (to work as
an alternative for the 'rep movs' case), _and_ in %rax (for the nocache
case).
We could avoid this by wrapping __copy_user_nocache() callers in an
inline asm, but since the cost is just an extra register copy, it's
probably not worth it.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
This is preparatory work for inlining the 'rep movs' case, but also a
cleanup. The __copy_user_nocache() function was mis-used by the rdma
code to do uncached kernel copies that don't actually want user copies
at all, and as a result doesn't want the stac/clac either.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
The modern target to use is FSRS (Fast Short REP STOS), and the other
cases should only be used for bigger areas (ie mainly things like page
clearing).
Note! This changes the conditional for the inlining from FSRM ("fast
short rep movs") to FSRS ("fast short rep stos").
We'll have a separate fixup for AMD microarchitectures that have a good
'rep stosb' yet do not set the new Intel-specific FSRS bit (because FSRM
was there first).
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
The modern target to use is FSRM (Fast Short REP MOVS), and the other
cases should only be used for bigger areas (ie mainly things like page
clearing).
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Virtual Trust Levels (VTL) helps enable Hyper-V Virtual Secure Mode (VSM)
feature. VSM is a set of hypervisor capabilities and enlightenments
offered to host and guest partitions which enable the creation and
management of new security boundaries within operating system software.
VSM achieves and maintains isolation through VTLs.
Add early initialization for Virtual Trust Levels (VTL). This includes
initializing the x86 platform for VTL and enabling boot support for
secondary CPUs to start in targeted VTL context. For now, only enable
the code for targeted VTL level as 2.
When starting an AP at a VTL other than VTL0, the AP must start directly
in 64-bit mode, bypassing the usual 16-bit -> 32-bit -> 64-bit mode
transition sequence that occurs after waking up an AP with SIPI whose
vector points to the 16-bit AP startup trampoline code.
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Stanislav Kinsburskii <stanislav.kinsburskii@gmail.com>
Link: https://lore.kernel.org/r/1681192532-15460-6-git-send-email-ssengar@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
|
|
Move hv_get_nmi_reason to .h file so it can be used in other
modules as well.
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/1681192532-15460-4-git-send-email-ssengar@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
|
|
Add structs and hypercalls required to enable VTL support on x86.
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Stanislav Kinsburskii <stanislav.kinsburskii@gmail.com>
Link: https://lore.kernel.org/r/1681192532-15460-3-git-send-email-ssengar@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
|
|
Make get/set_rtc_noop() to be public so that they can be used
in other modules as well.
Co-developed-by: Tianyu Lan <tiala@microsoft.com>
Signed-off-by: Tianyu Lan <tiala@microsoft.com>
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Reviewed-by: Wei Liu <wei.liu@kernel.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/1681192532-15460-2-git-send-email-ssengar@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
|
|
The usage of the BIT() macro in inline asm code was introduced in 6.3 by
the commit in the Fixes tag. However, this macro uses "1UL" for integer
constant suffixes in its shift operation, while gas before 2.28 does not
support the "L" suffix after a number, and gas before 2.27 does not
support the "U" suffix, resulting in build errors such as the following
with such versions:
./arch/x86/include/asm/uaccess_64.h:124: Error: found 'L', expected: ')'
./arch/x86/include/asm/uaccess_64.h:124: Error: junk at end of line,
first unrecognized character is `L'
However, the currently minimal binutils version the kernel supports is
2.25.
There's a single use of this macro here, revert to (1 << 0) that works
with such older binutils.
As an additional info, the binutils PRs which add support for those
suffixes are:
https://sourceware.org/bugzilla/show_bug.cgi?id=19910
https://sourceware.org/bugzilla/show_bug.cgi?id=20732
[ bp: Massage and extend commit message. ]
Fixes: 5d1dd961e743 ("x86/alternatives: Add alt_instr.flags")
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Link: https://lore.kernel.org/lkml/a9aae568-3046-306c-bd71-92c1fc8eeddc@linux.alibaba.com/
|
|
For PCI pass-thru devices in a Confidential VM, Hyper-V requires
that PCI config space be accessed via hypercalls. In normal VMs,
config space accesses are trapped to the Hyper-V host and emulated.
But in a confidential VM, the host can't access guest memory to
decode the instruction for emulation, so an explicit hypercall must
be used.
Add functions to make the new MMIO read and MMIO write hypercalls.
Update the PCI config space access functions to use the hypercalls
when such use is indicated by Hyper-V flags. Also, set the flag to
allow the Hyper-V PCI driver to be loaded and used in a Confidential
VM (a.k.a., "Isolation VM"). The driver has previously been hardened
against a malicious Hyper-V host[1].
[1] https://lore.kernel.org/all/20220511223207.3386-2-parri.andrea@gmail.com/
Co-developed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Link: https://lore.kernel.org/r/1679838727-87310-13-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
|
|
Merge the following 6 patches from tip/x86/sev, which are taken from
Michael Kelley's series [0]. The rest of Michael's series depend on
them.
x86/hyperv: Change vTOM handling to use standard coco mechanisms
init: Call mem_encrypt_init() after Hyper-V hypercall init is done
x86/mm: Handle decryption/re-encryption of bss_decrypted consistently
Drivers: hv: Explicitly request decrypted in vmap_pfn() calls
x86/hyperv: Reorder code to facilitate future work
x86/ioremap: Add hypervisor callback for private MMIO mapping in coco VM
0: https://lore.kernel.org/linux-hyperv/1679838727-87310-1-git-send-email-mikelley@microsoft.com/
|
|
Annotate the function prototype and definition as noreturn to prevent
objtool warnings like:
vmlinux.o: warning: objtool: hyperv_init+0x55c: unreachable instruction
Also, as per Josh's suggestion, add it to the global_noreturns list.
As a comparison, an objdump output without the annotation:
[...]
1b63: mov $0x1,%esi
1b68: xor %edi,%edi
1b6a: callq ffffffff8102f680 <hv_ghcb_terminate>
1b6f: jmpq ffffffff82f217ec <hyperv_init+0x9c> # unreachable
1b74: cmpq $0xffffffffffffffff,-0x702a24(%rip)
[...]
Now, after adding the __noreturn to the function prototype:
[...]
17df: callq ffffffff8102f6d0 <hv_ghcb_negotiate_protocol>
17e4: test %al,%al
17e6: je ffffffff82f21bb9 <hyperv_init+0x469>
[...] <many insns>
1bb9: mov $0x1,%esi
1bbe: xor %edi,%edi
1bc0: callq ffffffff8102f680 <hv_ghcb_terminate>
1bc5: nopw %cs:0x0(%rax,%rax,1) # end of function
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/32453a703dfcf0d007b473c9acbf70718222b74b.1681342859.git.jpoimboe@kernel.org
|
|
Fixes the following warning:
vmlinux.o: warning: objtool: resume_play_dead+0x21: unreachable instruction
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/ce1407c4bf88b1334fe40413126343792a77ca50.1681342859.git.jpoimboe@kernel.org
|
|
In preparation for improving objtool's handling of weak noreturn
functions, mark nmi_panic_self_stop() __noreturn.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/316fc6dfab5a8c4e024c7185484a1ee5fb0afb79.1681342859.git.jpoimboe@kernel.org
|
|
Now that start_kernel() is __noreturn, mark its chain of callers
__noreturn.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/c2525f96b88be98ee027ee0291d58003036d4120.1681342859.git.jpoimboe@kernel.org
|
|
CFI typed functions are failing to get padded properly for
CONFIG_CALL_PADDING.
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/721f0da48d2a49fe907225711b8b76a2b787f9a8.1681331135.git.jpoimboe@kernel.org
|
|
Refactor Hyper-V's range-based TLB flushing API to take a gfn+nr_pages
pair instead of a struct, and bury said struct in Hyper-V specific code.
Passing along two params generates much better code for the common case
where KVM is _not_ running on Hyper-V, as forwarding the flush on to
Hyper-V's hv_flush_remote_tlbs_range() from kvm_flush_remote_tlbs_range()
becomes a tail call.
Cc: David Matlack <dmatlack@google.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20230405003133.419177-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
