When user shadow stack is in use, Write=0,Dirty=1 is treated by the CPU as
shadow stack memory. So for shadow stack memory this bit combination is
valid, but when Dirty=1,Write=1 (conventionally writable) memory is being
write protected, the kernel has been taught to transition the Dirty=1
bit to SavedDirty=1, to avoid inadvertently creating shadow stack
memory. It does this inside pte_wrprotect() because it knows the PTE is
not intended to be a writable shadow stack entry, it is supposed to be
write protected.
However, when a PTE is created by a raw prot using mk_pte(), mk_pte()
can't know whether to adjust Dirty=1 to SavedDirty=1. It can't
distinguish between the caller intending to create a shadow stack PTE or
needing the SavedDirty shift.
The kernel has been updated to not do this, and so Write=0,Dirty=1
memory should only be created by the pte_mkfoo() helpers. Add a warning
to make sure no new mk_pte() start doing this, like, for example,
set_memory_rox() did.
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-19-rick.p.edgecombe%40intel.com
The x86 Control-flow Enforcement Technology (CET) feature includes a new
type of memory called shadow stack. This shadow stack memory has some
unusual properties, which requires some core mm changes to function
properly.
One sharp edge is that PTEs that are both Write=0 and Dirty=1 are
treated as shadow by the CPU, but this combination used to be created by
the kernel on x86. Previous patches have changed the kernel to now avoid
creating these PTEs unless they are for shadow stack memory. In case any
missed corners of the kernel are still creating PTEs like this for
non-shadow stack memory, and to catch any re-introductions of the logic,
warn if any shadow stack PTEs (Write=0, Dirty=1) are found in non-shadow
stack VMAs when they are being zapped. This won't catch transient cases
but should have decent coverage.
In order to check if a PTE is shadow stack in core mm code, add two arch
breakouts arch_check_zapped_pte/pmd(). This will allow shadow stack
specific code to be kept in arch/x86.
Only do the check if shadow stack is supported by the CPU and configured
because in rare cases older CPUs may write Dirty=1 to a Write=0 CPU on
older CPUs. This check is handled in pte_shstk()/pmd_shstk().
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-18-rick.p.edgecombe%40intel.com
The CPU performs "shadow stack accesses" when it expects to encounter
shadow stack mappings. These accesses can be implicit (via CALL/RET
instructions) or explicit (instructions like WRSS).
Shadow stack accesses to shadow-stack mappings can result in faults in
normal, valid operation just like regular accesses to regular mappings.
Shadow stacks need some of the same features like delayed allocation, swap
and copy-on-write. The kernel needs to use faults to implement those
features.
The architecture has concepts of both shadow stack reads and shadow stack
writes. Any shadow stack access to non-shadow stack memory will generate
a fault with the shadow stack error code bit set.
This means that, unlike normal write protection, the fault handler needs
to create a type of memory that can be written to (with instructions that
generate shadow stack writes), even to fulfill a read access. So in the
case of COW memory, the COW needs to take place even with a shadow stack
read. Otherwise the page will be left (shadow stack) writable in
userspace. So to trigger the appropriate behavior, set FAULT_FLAG_WRITE
for shadow stack accesses, even if the access was a shadow stack read.
For the purpose of making this clearer, consider the following example.
If a process has a shadow stack, and forks, the shadow stack PTEs will
become read-only due to COW. If the CPU in one process performs a shadow
stack read access to the shadow stack, for example executing a RET and
causing the CPU to read the shadow stack copy of the return address, then
in order for the fault to be resolved the PTE will need to be set with
shadow stack permissions. But then the memory would be changeable from
userspace (from CALL, RET, WRSS, etc). So this scenario needs to trigger
COW, otherwise the shared page would be changeable from both processes.
Shadow stack accesses can also result in errors, such as when a shadow
stack overflows, or if a shadow stack access occurs to a non-shadow-stack
mapping. Also, generate the errors for invalid shadow stack accesses.
Co-developed-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-16-rick.p.edgecombe%40intel.com
New processors that support Shadow Stack regard Write=0,Dirty=1 PTEs as
shadow stack pages.
In normal cases, it can be helpful to create Write=1 PTEs as also Dirty=1
if HW dirty tracking is not needed, because if the Dirty bit is not already
set the CPU has to set Dirty=1 when the memory gets written to. This
creates additional work for the CPU. So traditional wisdom was to simply
set the Dirty bit whenever you didn't care about it. However, it was never
really very helpful for read-only kernel memory.
When CR4.CET=1 and IA32_S_CET.SH_STK_EN=1, some instructions can write to
such supervisor memory. The kernel does not set IA32_S_CET.SH_STK_EN, so
avoiding kernel Write=0,Dirty=1 memory is not strictly needed for any
functional reason. But having Write=0,Dirty=1 kernel memory doesn't have
any functional benefit either, so to reduce ambiguity between shadow stack
and regular Write=0 pages, remove Dirty=1 from any kernel Write=0 PTEs.
Co-developed-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-14-rick.p.edgecombe%40intel.com
The recently introduced _PAGE_SAVED_DIRTY should be used instead of the
HW Dirty bit whenever a PTE is Write=0, in order to not inadvertently
create shadow stack PTEs. Update pte_mk*() helpers to do this, and apply
the same changes to pmd and pud. Since there is no x86 version of
pte_mkwrite() to hold this arch specific logic, create one. Add it to
x86/mm/pgtable.c instead of x86/asm/include/pgtable.h as future patches
will require it to live in pgtable.c and it will make the diff easier
for reviewers.
Since CPUs without shadow stack support could create Write=0,Dirty=1
PTEs, only return true for pte_shstk() if the CPU also supports shadow
stack. This will prevent these HW creates PTEs as showing as true for
pte_write().
For pte_modify() this is a bit trickier. It takes a "raw" pgprot_t which
was not necessarily created with any of the existing PTE bit helpers.
That means that it can return a pte_t with Write=0,Dirty=1, a shadow
stack PTE, when it did not intend to create one.
Modify it to also move _PAGE_DIRTY to _PAGE_SAVED_DIRTY. To avoid
creating Write=0,Dirty=1 PTEs, pte_modify() needs to avoid:
1. Marking Write=0 PTEs Dirty=1
2. Marking Dirty=1 PTEs Write=0
The first case cannot happen as the existing behavior of pte_modify() is to
filter out any Dirty bit passed in newprot. Handle the second case by
shifting _PAGE_DIRTY=1 to _PAGE_SAVED_DIRTY=1 if the PTE was write
protected by the pte_modify() call. Apply the same changes to pmd_modify().
Co-developed-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-13-rick.p.edgecombe%40intel.com
When shadow stack is in use, Write=0,Dirty=1 PTE are preserved for
shadow stack. Copy-on-write PTEs then have Write=0,SavedDirty=1.
When a PTE goes from Write=1,Dirty=1 to Write=0,SavedDirty=1, it could
become a transient shadow stack PTE in two cases:
1. Some processors can start a write but end up seeing a Write=0 PTE by
the time they get to the Dirty bit, creating a transient shadow stack
PTE. However, this will not occur on processors supporting shadow
stack, and a TLB flush is not necessary.
2. When _PAGE_DIRTY is replaced with _PAGE_SAVED_DIRTY non-atomically, a
transient shadow stack PTE can be created as a result.
Prevent the second case when doing a write protection and Dirty->SavedDirty
shift at the same time with a CMPXCHG loop. The first case
Note, in the PAE case CMPXCHG will need to operate on 8 byte, but
try_cmpxchg() will not use CMPXCHG8B, so it cannot operate on a full PAE
PTE. However the exiting logic is not operating on a full 8 byte region
either, and relies on the fact that the Write bit is in the first 4
bytes when doing the clear_bit(). Since both the Dirty, SavedDirty and
Write bits are in the first 4 bytes, casting to a long will be similar to
the existing behavior which also casts to a long.
Dave Hansen, Jann Horn, Andy Lutomirski, and Peter Zijlstra provided many
insights to the issue. Jann Horn provided the CMPXCHG solution.
Co-developed-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-12-rick.p.edgecombe%40intel.com
Some OSes have a greater dependence on software available bits in PTEs than
Linux. That left the hardware architects looking for a way to represent a
new memory type (shadow stack) within the existing bits. They chose to
repurpose a lightly-used state: Write=0,Dirty=1. So in order to support
shadow stack memory, Linux should avoid creating memory with this PTE bit
combination unless it intends for it to be shadow stack.
The reason it's lightly used is that Dirty=1 is normally set by HW
_before_ a write. A write with a Write=0 PTE would typically only generate
a fault, not set Dirty=1. Hardware can (rarely) both set Dirty=1 *and*
generate the fault, resulting in a Write=0,Dirty=1 PTE. Hardware which
supports shadow stacks will no longer exhibit this oddity.
So that leaves Write=0,Dirty=1 PTEs created in software. To avoid
inadvertently created shadow stack memory, in places where Linux normally
creates Write=0,Dirty=1, it can use the software-defined _PAGE_SAVED_DIRTY
in place of the hardware _PAGE_DIRTY. In other words, whenever Linux needs
to create Write=0,Dirty=1, it instead creates Write=0,SavedDirty=1 except
for shadow stack, which is Write=0,Dirty=1.
There are six bits left available to software in the 64-bit PTE after
consuming a bit for _PAGE_SAVED_DIRTY. For 32 bit, the same bit as
_PAGE_BIT_UFFD_WP is used, since user fault fd is not supported on 32
bit. This leaves one unused software bit on 32 bit (_PAGE_BIT_SOFT_DIRTY,
as this is also not supported on 32 bit).
Implement only the infrastructure for _PAGE_SAVED_DIRTY. Changes to
actually begin creating _PAGE_SAVED_DIRTY PTEs will follow once other
pieces are in place.
Since this SavedDirty shifting is done for all x86 CPUs, this leaves
the possibility for the hardware oddity to still create Write=0,Dirty=1
PTEs in rare cases. Since these CPUs also don't support shadow stack, this
will be harmless as it was before the introduction of SavedDirty.
Implement the shifting logic to be branchless. Embed the logic of whether
to do the shifting (including checking the Write bits) so that it can be
called by future callers that would otherwise need additional branching
logic. This efficiency allows the logic of when to do the shifting to be
centralized, making the code easier to reason about.
Co-developed-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-11-rick.p.edgecombe%40intel.com
The Control-Flow Enforcement Technology contains two related features,
one of which is Shadow Stacks. Future patches will utilize this feature
for shadow stack support in KVM, so add a CPU feature flags for Shadow
Stacks (CPUID.(EAX=7,ECX=0):ECX[bit 7]).
To protect shadow stack state from malicious modification, the registers
are only accessible in supervisor mode. This implementation
context-switches the registers with XSAVES. Make X86_FEATURE_SHSTK depend
on XSAVES.
The shadow stack feature, enumerated by the CPUID bit described above,
encompasses both supervisor and userspace support for shadow stack. In
near future patches, only userspace shadow stack will be enabled. In
expectation of future supervisor shadow stack support, create a software
CPU capability to enumerate kernel utilization of userspace shadow stack
support. This user shadow stack bit should depend on the HW "shstk"
capability and that logic will be implemented in future patches.
Co-developed-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-9-rick.p.edgecombe%40intel.com
Shadow stack provides protection for applications against function return
address corruption. It is active when the processor supports it, the
kernel has CONFIG_X86_SHADOW_STACK enabled, and the application is built
for the feature. This is only implemented for the 64-bit kernel. When it
is enabled, legacy non-shadow stack applications continue to work, but
without protection.
Since there is another feature that utilizes CET (Kernel IBT) that will
share implementation with shadow stacks, create CONFIG_CET to signify
that at least one CET feature is configured.
Co-developed-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-7-rick.p.edgecombe%40intel.com
The x86 Shadow stack feature includes a new type of memory called shadow
stack. This shadow stack memory has some unusual properties, which requires
some core mm changes to function properly.
One of these unusual properties is that shadow stack memory is writable,
but only in limited ways. These limits are applied via a specific PTE
bit combination. Nevertheless, the memory is writable, and core mm code
will need to apply the writable permissions in the typical paths that
call pte_mkwrite(). Future patches will make pte_mkwrite() take a VMA, so
that the x86 implementation of it can know whether to create regular
writable or shadow stack mappings.
But there are a couple of challenges to this. Modifying the signatures of
each arch pte_mkwrite() implementation would be error prone because some
are generated with macros and would need to be re-implemented. Also, some
pte_mkwrite() callers operate on kernel memory without a VMA.
So this can be done in a three step process. First pte_mkwrite() can be
renamed to pte_mkwrite_novma() in each arch, with a generic pte_mkwrite()
added that just calls pte_mkwrite_novma(). Next callers without a VMA can
be moved to pte_mkwrite_novma(). And lastly, pte_mkwrite() and all callers
can be changed to take/pass a VMA.
Earlier work did the first step, so next move the callers that don't have
a VMA to pte_mkwrite_novma(). Also do the same for pmd_mkwrite(). This
will be ok for the shadow stack feature, as these callers are on kernel
memory which will not need to be made shadow stack, and the other
architectures only currently support one type of memory in pte_mkwrite()
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/all/20230613001108.3040476-3-rick.p.edgecombe%40intel.com
The x86 Shadow stack feature includes a new type of memory called shadow
stack. This shadow stack memory has some unusual properties, which requires
some core mm changes to function properly.
One of these unusual properties is that shadow stack memory is writable,
but only in limited ways. These limits are applied via a specific PTE
bit combination. Nevertheless, the memory is writable, and core mm code
will need to apply the writable permissions in the typical paths that
call pte_mkwrite(). The goal is to make pte_mkwrite() take a VMA, so
that the x86 implementation of it can know whether to create regular
writable or shadow stack mappings.
But there are a couple of challenges to this. Modifying the signatures of
each arch pte_mkwrite() implementation would be error prone because some
are generated with macros and would need to be re-implemented. Also, some
pte_mkwrite() callers operate on kernel memory without a VMA.
So this can be done in a three step process. First pte_mkwrite() can be
renamed to pte_mkwrite_novma() in each arch, with a generic pte_mkwrite()
added that just calls pte_mkwrite_novma(). Next callers without a VMA can
be moved to pte_mkwrite_novma(). And lastly, pte_mkwrite() and all callers
can be changed to take/pass a VMA.
Start the process by renaming pte_mkwrite() to pte_mkwrite_novma() and
adding the pte_mkwrite() wrapper in linux/pgtable.h. Apply the same
pattern for pmd_mkwrite(). Since not all archs have a pmd_mkwrite_novma(),
create a new arch config HAS_HUGE_PAGE that can be used to tell if
pmd_mkwrite() should be defined. Otherwise in the !HAS_HUGE_PAGE cases the
compiler would not be able to find pmd_mkwrite_novma().
No functional change.
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/lkml/CAHk-=wiZjSu7c9sFYZb3q04108stgHff2wfbokGCCgW7riz+8Q@mail.gmail.com/
Link: https://lore.kernel.org/all/20230613001108.3040476-2-rick.p.edgecombe%40intel.com
Pull x86 fpu fix from Borislav Petkov:
- Do FPU AP initialization on Xen PV too which got missed by the recent
boot reordering work
* tag 'x86_urgent_for_v6.5_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/xen: Fix secondary processors' FPU initialization
Pull x86 fix from Thomas Gleixner:
"A single fix for the mechanism to park CPUs with an INIT IPI.
On shutdown or kexec, the kernel tries to park the non-boot CPUs with
an INIT IPI. But the same code path is also used by the crash utility.
If the CPU which panics is not the boot CPU then it sends an INIT IPI
to the boot CPU which resets the machine.
Prevent this by validating that the CPU which runs the stop mechanism
is the boot CPU. If not, leave the other CPUs in HLT"
* tag 'x86-core-2023-07-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/smp: Don't send INIT to boot CPU
Pull MIPS fixes from Thomas Bogendoerfer:
- fixes for KVM
- fix for loongson build and cpu probing
- DT fixes
* tag 'mips_6.5_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
MIPS: kvm: Fix build error with KVM_MIPS_DEBUG_COP0_COUNTERS enabled
MIPS: dts: add missing space before {
MIPS: Loongson: Fix build error when make modules_install
MIPS: KVM: Fix NULL pointer dereference
MIPS: Loongson: Fix cpu_probe_loongson() again
Pull more RISC-V updates from Palmer Dabbelt:
- A bunch of fixes/cleanups from the first part of the merge window,
mostly related to ACPI and vector as those were large
- Some documentation improvements, mostly related to the new code
- The "riscv,isa" DT key is deprecated
- Support for link-time dead code elimination
- Support for minor fault registration in userfaultd
- A handful of cleanups around CMO alternatives
* tag 'riscv-for-linus-6.5-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (23 commits)
riscv: mm: mark noncoherent_supported as __ro_after_init
riscv: mm: mark CBO relate initialization funcs as __init
riscv: errata: thead: only set cbom size & noncoherent during boot
riscv: Select HAVE_ARCH_USERFAULTFD_MINOR
RISC-V: Document the ISA string parsing rules for ACPI
risc-v: Fix order of IPI enablement vs RCU startup
mm: riscv: fix an unsafe pte read in huge_pte_alloc()
dt-bindings: riscv: deprecate riscv,isa
RISC-V: drop error print from riscv_hartid_to_cpuid()
riscv: Discard vector state on syscalls
riscv: move memblock_allow_resize() after linear mapping is ready
riscv: Enable ARCH_SUSPEND_POSSIBLE for s2idle
riscv: vdso: include vdso/vsyscall.h for vdso_data
selftests: Test RISC-V Vector's first-use handler
riscv: vector: clear V-reg in the first-use trap
riscv: vector: only enable interrupts in the first-use trap
RISC-V: Fix up some vector state related build failures
RISC-V: Document that V registers are clobbered on syscalls
riscv: disable HAVE_LD_DEAD_CODE_DATA_ELIMINATION for LLD
riscv: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION
...
Pull powerpc fixes from Michael Ellerman:
- Fix PCIe MEM size for pci2 node on Turris 1.x boards
- Two minor build fixes
Thanks to Christophe Leroy, Douglas Anderson, Pali Rohár, Petr Mladek,
and Randy Dunlap.
* tag 'powerpc-6.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc: dts: turris1x.dts: Fix PCIe MEM size for pci2 node
powerpc: Include asm/nmi.c in mobility.c for watchdog_hardlockup_set_timeout_pct()
powerpc: allow PPC_EARLY_DEBUG_CPM only when SERIAL_CPM=y
Parking CPUs in INIT works well, except for the crash case when the CPU
which invokes smp_park_other_cpus_in_init() is not the boot CPU. Sending
INIT to the boot CPU resets the whole machine.
Prevent this by validating that this runs on the boot CPU. If not fall back
and let CPUs hang in HLT.
Fixes: 45e34c8af5 ("x86/smp: Put CPUs into INIT on shutdown if possible")
Reported-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/87ttui91jo.ffs@tglx
Commit e4de205769 ("MIPS: KVM: Fix NULL pointer dereference") missed
converting one place accessing cop0 registers, which results in a build
error, if KVM_MIPS_DEBUG_COP0_COUNTERS is enabled.
Fixes: e4de205769 ("MIPS: KVM: Fix NULL pointer dereference")
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Pull drm fixes from Dave Airlie:
"Lots of fixes, mostly i915 and amdgpu. It's two weeks of i915, and I
think three weeks of amdgpu.
fbdev:
- Fix module infos on sparc
panel:
- Fix mode on Starry-ili9882t
i915:
- Allow DC states along with PW2 only for PWB functionality [adlp+]
- Fix SSC selection for MPLLA [mtl]
- Use hw.adjusted mode when calculating io/fast wake times [psr]
- Apply min softlimit correctly [guc/slpc]
- Assign correct hdcp content type [hdcp]
- Add missing forward declarations/includes to display power headers
- Fix BDW PSR AUX CH data register offsets [psr]
- Use mock device info for creating mock device
amdgpu:
- Misc cleanups
- GFX 9.4.3 fixes
- DEBUGFS build fix
- Fix LPDDR5 reporting
- ASPM fixes
- DCN 3.1.4 fixes
- DP MST fixes
- DCN 3.2.x fixes
- Display PSR TCON fixes
- SMU 13.x fixes
- RAS fixes
- Vega12/20 SMU fixes
- PSP flashing cleanup
- GFX9 MCBP fixes
- SR-IOV fixes
- GPUVM clear mappings fix for always valid BOs
- Add FAMS quirk for problematic monitor
- Fix possible UAF
- Better handle monentary temperature fluctuations
- SDMA 4.4.2 fixes
- Fencing fix"
* tag 'drm-next-2023-07-07' of git://anongit.freedesktop.org/drm/drm: (83 commits)
drm/i915: use mock device info for creating mock device
drm/i915/psr: Fix BDW PSR AUX CH data register offsets
drm/amdgpu: Fix potential fence use-after-free v2
drm/amd/pm: avoid unintentional shutdown due to temperature momentary fluctuation
drm/amd/pm: expose swctf threshold setting for legacy powerplay
drm/amd/display: 3.2.241
drm/amd/display: Take full update path if number of planes changed
drm/amd/display: Create debugging mechanism for Gaming FAMS
drm/amd/display: Add monitor specific edid quirk
drm/amd/display: For new fast update path, loop through each surface
drm/amd/display: Remove Phantom Pipe Check When Calculating K1 and K2
drm/amd/display: Limit new fast update path to addr and gamma / color
drm/amd/display: Fix the delta clamping for shaper LUT
drm/amdgpu: Keep non-psp path for partition switch
drm/amd/display: program DPP shaper and 3D LUT if updated
Revert "drm/amd/display: edp do not add non-edid timings"
drm/amdgpu: share drm device for pci amdgpu device with 1st partition device
drm/amd/pm: Add GFX v9.4.3 unique id to sysfs
drm/amd/pm: Enable pp_feature attribute
drm/amdgpu/vcn: Need to unpause dpg before stop dpg
...
Pull tracing fixes from Steven Rostedt:
- Fix bad git merge of #endif in arm64 code
A merge of the arm64 tree caused #endif to go into the wrong place
- Fix crash on lseek of write access to tracefs/error_log
Opening error_log as write only, and then doing an lseek() causes a
kernel panic, because the lseek() handle expects a "seq_file" to
exist (which is not done on write only opens). Use tracing_lseek()
that tests for this instead of calling the default seq lseek handler.
- Check for negative instead of -E2BIG for error on strscpy() returns
Instead of testing for -E2BIG from strscpy(), to be more robust,
check for less than zero, which will make sure it catches any error
that strscpy() may someday return.
* tag 'trace-v6.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/boot: Test strscpy() against less than zero for error
arm64: ftrace: fix build error with CONFIG_FUNCTION_GRAPH_TRACER=n
tracing: Fix null pointer dereference in tracing_err_log_open()
Pull more s390 updates from Alexander Gordeev:
- Fix virtual vs physical address confusion in vmem_add_range() and
vmem_remove_range() functions
- Include <linux/io.h> instead of <asm/io.h> and <asm-generic/io.h>
throughout s390 code
- Make all PSW related defines also available for assembler files.
Remove PSW_DEFAULT_KEY define from uapi for that
- When adding an undefined symbol the build still succeeds, but
userspace crashes trying to execute VDSO, because the symbol is not
resolved. Add undefined symbols check to prevent that
- Use kvmalloc_array() instead of kzalloc() for allocaton of 256k
memory when executing s390 crypto adapter IOCTL
- Add -fPIE flag to prevent decompressor misaligned symbol build error
with clang
- Use .balign instead of .align everywhere. This is a no-op for s390,
but with this there no mix in using .align and .balign anymore
- Filter out -mno-pic-data-is-text-relative flag when compiling kernel
to prevent VDSO build error
- Rework entering of DAT-on mode on CPU restart to use PSW_KERNEL_BITS
mask directly
- Do not retry administrative requests to some s390 crypto cards, since
the firmware assumes replay attacks
- Remove most of the debug code, which is build in when kernel config
option CONFIG_ZCRYPT_DEBUG is enabled
- Remove CONFIG_ZCRYPT_MULTIDEVNODES kernel config option and switch
off the multiple devices support for the s390 zcrypt device driver
- With the conversion to generic entry machine checks are accounted to
the current context instead of irq time. As result, the STCKF
instruction at the beginning of the machine check handler and the
lowcore member are no longer required, therefore remove it
- Fix various typos found with codespell
- Minor cleanups to CPU-measurement Counter and Sampling Facilities
code
- Revert patch that removes VMEM_MAX_PHYS macro, since it causes a
regression
* tag 's390-6.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (25 commits)
Revert "s390/mm: get rid of VMEM_MAX_PHYS macro"
s390/cpum_sf: remove check on CPU being online
s390/cpum_sf: handle casts consistently
s390/cpum_sf: remove unnecessary debug statement
s390/cpum_sf: remove parameter in call to pr_err
s390/cpum_sf: simplify function setup_pmu_cpu
s390/cpum_cf: remove unneeded debug statements
s390/entry: remove mcck clock
s390: fix various typos
s390/zcrypt: remove ZCRYPT_MULTIDEVNODES kernel config option
s390/zcrypt: do not retry administrative requests
s390/zcrypt: cleanup some debug code
s390/entry: rework entering DAT-on mode on CPU restart
s390/mm: fence off VM macros from asm and linker
s390: include linux/io.h instead of asm/io.h
s390/ptrace: make all psw related defines also available for asm
s390/ptrace: remove PSW_DEFAULT_KEY from uapi
s390/vdso: filter out mno-pic-data-is-text-relative cflag
s390: consistently use .balign instead of .align
s390/decompressor: fix misaligned symbol build error
...
Pull asm-generic updates from Arnd Bergmann:
"These are cleanups for architecture specific header files:
- the comments in include/linux/syscalls.h have gone out of sync and
are really pointless, so these get removed
- The asm/bitsperlong.h header no longer needs to be architecture
specific on modern compilers, so use a generic version for newer
architectures that use new enough userspace compilers
- A cleanup for virt_to_pfn/virt_to_bus to have proper type checking,
forcing the use of pointers"
* tag 'asm-generic-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
syscalls: Remove file path comments from headers
tools arch: Remove uapi bitsperlong.h of hexagon and microblaze
asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarch
m68k/mm: Make pfn accessors static inlines
arm64: memory: Make virt_to_pfn() a static inline
ARM: mm: Make virt_to_pfn() a static inline
asm-generic/page.h: Make pfn accessors static inlines
xen/netback: Pass (void *) to virt_to_page()
netfs: Pass a pointer to virt_to_page()
cifs: Pass a pointer to virt_to_page() in cifsglob
cifs: Pass a pointer to virt_to_page()
riscv: mm: init: Pass a pointer to virt_to_page()
ARC: init: Pass a pointer to virt_to_pfn() in init
m68k: Pass a pointer to virt_to_pfn() virt_to_page()
fs/proc/kcore.c: Pass a pointer to virt_addr_valid()
Pull SoC fixes from Arnd Bergmann:
"There are three small fixes that came up sincie the past week:
- an incorrect bit offset in ixp4xx bus driver
- a riscv randconfig regression in the thead platform I merged
- whitespace fixes for some dts files"
* tag 'soc-fixes-6.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
bus: ixp4xx: fix IXP4XX_EXP_T1_MASK
ARM: dts: st: add missing space before {
RISC-V: make ARCH_THEAD preclude XIP_KERNEL
Pull sh updates from Adrian Glaubitz:
"Fix a compiler warning in the J2 probing code and a fix by Sergey
Shtylyov to avoid using IRQ0 on SH3 and SH4 targets. Masahiro Yamada
made some clean-up in the build system to address reports by the 0day
bot.
The most notable changes come from Artur Rojek who addressed a number
of issues in the DMA code, in particular a fix for the DMA channel
offset calculation that was introduced in in 7f47c7189b ("sh: dma:
More legacy cpu dma chainsawing.") in 2012!
Together with another change to correct the number of DMA channels for
each SuperH SoC according to specification, Artur's series unbreaks
the kernel on the SH7709 SoC allowing Linux to boot on the HP Jornada
680 handheld again.
Summary:
- Provide unxlate_dev_mem_ptr() in asm/io.h
- dma: Correct the number of DMA channels for SH7709
- dma: Drop incorrect SH_DMAC_BASE1 definition for SH4
- dma: Fix DMA channel offset calculation
- Remove compiler flag duplication
- Refactor header include path addition
- Move build rule for cchips/hd6446x/ to arch/sh/Kbuild
- Fix -Wmissing-include-dirs warnings for various platforms
- Avoid using IRQ0 on SH3 and SH4
- j2: Use ioremap() to translate device tree address into kernel
memory"
* tag 'sh-for-v6.5-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/glaubitz/sh-linux:
sh: Provide unxlate_dev_mem_ptr() in asm/io.h
sh: dma: Correct the number of DMA channels for SH7709
sh: dma: Drop incorrect SH_DMAC_BASE1 definition for SH4
sh: dma: Fix DMA channel offset calculation
sh: Remove compiler flag duplication
sh: Refactor header include path addition
sh: Move build rule for cchips/hd6446x/ to arch/sh/Kbuild
sh: Fix -Wmissing-include-dirs warnings for various platforms
sh: Avoid using IRQ0 on SH3 and SH4
sh: j2: Use ioremap() to translate device tree address into kernel memory
Pull more parisc architecture updates from Helge Deller:
- Fix all compiler warnings in arch/parisc and drivers/parisc when
compiled with W=1
* tag 'parisc-for-6.5-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: syscalls: Avoid compiler warnings with W=1
parisc: math-emu: Avoid compiler warnings with W=1
parisc: Raise minimal GCC version to 12.0.0
parisc: unwind: Avoid missing prototype warning for handle_interruption()
parisc: smp: Add declaration for start_cpu_itimer()
parisc: pdt: Get prototype for arch_report_meminfo()
The unxlate_dev_mem_ptr() function has no prototype on the sh architecture
which does not include asm-generic/io.h. This results in the following
build failure:
drivers/char/mem.c: In function 'read_mem':
drivers/char/mem.c:164:25: error: implicit declaration of function 'unxlate_dev_mem_ptr'
This compile error is now seen because commit 99b619b37a ("mips: provide
unxlate_dev_mem_ptr() in asm/io.h") removed the weak function which was
previously in place to handle this problem.
Add a trivial macro to the sh header to provide the now missing dummy
function.
Fixes: 99b619b37a ("mips: provide unxlate_dev_mem_ptr() in asm/io.h")
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/20230704190144.2888679-1-linux@roeck-us.net
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Various SoCs of the SH3, SH4 and SH4A family, which use this driver,
feature a differing number of DMA channels, which can be distributed
between up to two DMAC modules. The existing implementation fails to
correctly accommodate for all those variations, resulting in wrong
channel offset calculations and leading to kernel panics.
Rewrite dma_base_addr() in order to properly calculate channel offsets
in a DMAC module. Fix dmaor_read_reg() and dmaor_write_reg(), so that
the correct DMAC module base is selected for the DMAOR register.
Fixes: 7f47c7189b ("sh: dma: More legacy cpu dma chainsawing.")
Signed-off-by: Artur Rojek <contact@artur-rojek.eu>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/20230527164452.64797-2-contact@artur-rojek.eu
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Every compiler flag added by arch/sh/Makefile is passed to the
compiler twice:
$(KBUILD_CPPFLAGS) + $(KBUILD_CFLAGS) is used for compiling *.c
$(KBUILD_CPPFLAGS) + $(KBUILD_AFLAGS) is used for compiling *.S
Given the above, adding $(cflags-y) to all of KBUILD_{CPP/C/A}FLAGS
ends up with duplication.
Add -I options to $(KBUILD_CPPFLAGS), and the rest of $(cflags-y)
to KBUILD_{C,A}FLAGS.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/20230219141555.2308306-4-masahiroy@kernel.org
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
The 0day bot reports a lot of warnings (or errors due to CONFIG_WERROR)
like this:
cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs]
Indeed, arch/sh/include/mach-hp6xx does not exist.
While -Wmissing-include-dirs is only a W=1 warning, it may be
annoying when CONFIG_BTRFS_FS is enabled because fs/btrfs/Makefile
unconditionally adds this warning option.
arch/sh/Makefile defines machdir-y for two purposes:
- Build platform code in arch/sh/boards/mach-*/
- Add arch/sh/include/mach-*/ to the header search path
For the latter, some platforms use arch/sh/include/mach-common/
instead of having its own arch/sh/include/mach-*/.
Drop unneeded machdir-y to omit non-existing include directories.
To build arch/sh/boards/mach-*/, use the standard obj-y syntax in
arch/sh/boards/Makefile.
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202302190641.30VVXnPb-lkp@intel.com/
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/20230219141555.2308306-1-masahiroy@kernel.org
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
The WARN_ON_ONCE() statement in riscv's huge_pte_alloc() is susceptible
to false positives, because the pte is read twice at the C language
level, locklessly, within the same conditional statement. Depending on
compiler behavior, this can lead to generated machine code that actually
reads the pte just once, or twice. Reading twice will expose the code to
changing pte values and cause incorrect behavior.
In [1], similar code actually caused a kernel crash on 64-bit x86, when
using clang to build the kernel, but only after the conversion from *pte
reads, to ptep_get(pte). The latter uses READ_ONCE(), which forced a
double read of *pte.
Rather than waiting for the upcoming ptep_get() conversion, just convert
this part of the code now, but in a way that avoids the above problem:
take a single snapshot of the pte before using it in the WARN
conditional.
As expected, this preparatory step does not actually change the
generated code ("make mm/hugetlbpage.s"), on riscv64, when using a gcc
12.2 cross compiler.
[1] https://lore.kernel.org/20230630013203.1955064-1-jhubbard@nvidia.com
Suggested-by: James Houghton <jthoughton@google.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Link: https://lore.kernel.org/r/20230703190044.311730-1-jhubbard@nvidia.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
It appears that a merge conflict ended up hiding a newly added constant
in some configurations:
arch/arm64/kernel/entry-ftrace.S: Assembler messages:
arch/arm64/kernel/entry-ftrace.S:59: Error: undefined symbol FTRACE_OPS_DIRECT_CALL used as an immediate value
FTRACE_OPS_DIRECT_CALL is still used when CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
is enabled, even if CONFIG_FUNCTION_GRAPH_TRACER is disabled, so change the
ifdef accordingly.
Link: https://lkml.kernel.org/r/20230623152204.2216297-1-arnd@kernel.org
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Donglin Peng <pengdonglin@sangfor.com.cn>
Fixes: 3646970322 ("arm64: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Florent Revest <revest@chromium.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Moving the call of fpu__init_cpu() from cpu_init() to start_secondary()
broke Xen PV guests, as those don't call start_secondary() for APs.
Call fpu__init_cpu() in Xen's cpu_bringup(), which is the Xen PV
replacement of start_secondary().
Fixes: b81fac906a ("x86/fpu: Move FPU initialization into arch_cpu_finalize_init()")
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>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230703130032.22916-1-jgross@suse.com
Pull scope-based resource management infrastructure from Peter Zijlstra:
"These are the first few patches in the Scope-based Resource Management
series that introduce the infrastructure but not any conversions as of
yet.
Adding the infrastructure now allows multiple people to start using
them.
Of note is that Sparse will need some work since it doesn't yet
understand this attribute and might have decl-after-stmt issues"
* tag 'core_guards_for_6.5_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue:
kbuild: Drop -Wdeclaration-after-statement
locking: Introduce __cleanup() based infrastructure
apparmor: Free up __cleanup() name
dmaengine: ioat: Free up __cleanup() name
As of commit 2ac8743437 ("RISC-V: split early & late of_node to
hartid mapping") my CI complains about newly added pr_err() messages
during boot, for example:
[ 0.000000] Couldn't find cpu id for hartid [0]
[ 0.000000] riscv-intc: unable to find hart id for /cpus/cpu@0/interrupt-controller
Before the split, riscv_of_processor_hartid() contained a check for
whether the cpu was "available", before calling riscv_hartid_to_cpuid(),
but after the split riscv_of_processor_hartid() can be called for cpus
that are disabled.
Most callers of riscv_hartid_to_cpuid() already report custom errors
where it falls, making this print superfluous in those case. In other
places, the print adds nothing - see riscv_intc_init() for example.
Fixes: 2ac8743437 ("RISC-V: split early & late of_node to hartid mapping")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230629-paternity-grafted-b901b76d04a0@wendy
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
