Fix the SCS debug usage check so that we report the number of bytes
used, rather than the number of entries.
Fixes: 5bbaf9d1fc ("scs: Add support for stack usage debugging")
Reported-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Will Deacon <will@kernel.org>
Support for Clang's Shadow Call Stack in the kernel
(Sami Tolvanen and Will Deacon)
* for-next/scs:
arm64: entry-ftrace.S: Update comment to indicate that x18 is live
scs: Move DEFINE_SCS macro into core code
scs: Remove references to asm/scs.h from core code
scs: Move scs_overflow_check() out of architecture code
arm64: scs: Use 'scs_sp' register alias for x18
scs: Move accounting into alloc/free functions
arm64: scs: Store absolute SCS stack pointer value in thread_info
efi/libstub: Disable Shadow Call Stack
arm64: scs: Add shadow stacks for SDEI
arm64: Implement Shadow Call Stack
arm64: Disable SCS for hypervisor code
arm64: vdso: Disable Shadow Call Stack
arm64: efi: Restore register x18 if it was corrupted
arm64: Preserve register x18 when CPU is suspended
arm64: Reserve register x18 from general allocation with SCS
scs: Disable when function graph tracing is enabled
scs: Add support for stack usage debugging
scs: Add page accounting for shadow call stack allocations
scs: Add support for Clang's Shadow Call Stack (SCS)
KVM CPU errata rework
(Andrew Scull and Marc Zyngier)
* for-next/kvm/errata:
KVM: arm64: Move __load_guest_stage2 to kvm_mmu.h
arm64: Unify WORKAROUND_SPECULATIVE_AT_{NVHE,VHE}
Support for Branch Target Identification (BTI) in user and kernel
(Mark Brown and others)
* for-next/bti: (39 commits)
arm64: vdso: Fix CFI directives in sigreturn trampoline
arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instruction
arm64: bti: Fix support for userspace only BTI
arm64: kconfig: Update and comment GCC version check for kernel BTI
arm64: vdso: Map the vDSO text with guarded pages when built for BTI
arm64: vdso: Force the vDSO to be linked as BTI when built for BTI
arm64: vdso: Annotate for BTI
arm64: asm: Provide a mechanism for generating ELF note for BTI
arm64: bti: Provide Kconfig for kernel mode BTI
arm64: mm: Mark executable text as guarded pages
arm64: bpf: Annotate JITed code for BTI
arm64: Set GP bit in kernel page tables to enable BTI for the kernel
arm64: asm: Override SYM_FUNC_START when building the kernel with BTI
arm64: bti: Support building kernel C code using BTI
arm64: Document why we enable PAC support for leaf functions
arm64: insn: Report PAC and BTI instructions as skippable
arm64: insn: Don't assume unrecognized HINTs are skippable
arm64: insn: Provide a better name for aarch64_insn_is_nop()
arm64: insn: Add constants for new HINT instruction decode
arm64: Disable old style assembly annotations
...
ACPI and IORT updates
(Lorenzo Pieralisi)
* for-next/acpi:
ACPI/IORT: Remove the unused __get_pci_rid()
ACPI/IORT: Fix PMCG node single ID mapping handling
ACPI: IORT: Add comments for not calling acpi_put_table()
ACPI: GTDT: Put GTDT table after parsing
ACPI: IORT: Add extra message "applying workaround" for off-by-1 issue
ACPI/IORT: work around num_ids ambiguity
Revert "ACPI/IORT: Fix 'Number of IDs' handling in iort_id_map()"
ACPI/IORT: take _DMA methods into account for named components
BPF JIT optimisations for immediate value generation
(Luke Nelson)
* for-next/bpf:
bpf, arm64: Optimize ADD,SUB,JMP BPF_K using arm64 add/sub immediates
bpf, arm64: Optimize AND,OR,XOR,JSET BPF_K using arm64 logical immediates
arm64: insn: Fix two bugs in encoding 32-bit logical immediates
Addition of new CPU ID register fields and removal of some benign sanity checks
(Anshuman Khandual and others)
* for-next/cpufeature: (27 commits)
KVM: arm64: Check advertised Stage-2 page size capability
arm64/cpufeature: Add get_arm64_ftr_reg_nowarn()
arm64/cpuinfo: Add ID_MMFR4_EL1 into the cpuinfo_arm64 context
arm64/cpufeature: Add remaining feature bits in ID_AA64PFR1 register
arm64/cpufeature: Add remaining feature bits in ID_AA64PFR0 register
arm64/cpufeature: Add remaining feature bits in ID_AA64ISAR0 register
arm64/cpufeature: Add remaining feature bits in ID_MMFR4 register
arm64/cpufeature: Add remaining feature bits in ID_PFR0 register
arm64/cpufeature: Introduce ID_MMFR5 CPU register
arm64/cpufeature: Introduce ID_DFR1 CPU register
arm64/cpufeature: Introduce ID_PFR2 CPU register
arm64/cpufeature: Make doublelock a signed feature in ID_AA64DFR0
arm64/cpufeature: Drop TraceFilt feature exposure from ID_DFR0 register
arm64/cpufeature: Add explicit ftr_id_isar0[] for ID_ISAR0 register
arm64/cpufeature: Drop open encodings while extracting parange
arm64/cpufeature: Validate hypervisor capabilities during CPU hotplug
arm64: cpufeature: Group indexed system register definitions by name
arm64: cpufeature: Extend comment to describe absence of field info
arm64: drop duplicate definitions of ID_AA64MMFR0_TGRAN constants
arm64: cpufeature: Add an overview comment for the cpufeature framework
...
Minor documentation tweaks for silicon errata and booting requirements
(Rob Herring and Will Deacon)
* for-next/docs:
arm64: silicon-errata.rst: Sort the Cortex-A55 entries
arm64: docs: Mandate that the I-cache doesn't hold stale kernel text
Minor Kconfig cleanups
(Geert Uytterhoeven)
* for-next/kconfig:
arm64: cpufeature: Add "or" to mitigations for multiple errata
arm64: Sort vendor-specific errata
Miscellaneous updates
(Ard Biesheuvel and others)
* for-next/misc:
arm64: mm: Add asid_gen_match() helper
arm64: stacktrace: Factor out some common code into on_stack()
arm64: Call debug_traps_init() from trap_init() to help early kgdb
arm64: cacheflush: Fix KGDB trap detection
arm64/cpuinfo: Move device_initcall() near cpuinfo_regs_init()
arm64: kexec_file: print appropriate variable
arm: mm: use __pfn_to_section() to get mem_section
arm64: Reorder the macro arguments in the copy routines
efi/libstub/arm64: align PE/COFF sections to segment alignment
KVM: arm64: Drop PTE_S2_MEMATTR_MASK
arm64/kernel: Fix range on invalidating dcache for boot page tables
arm64: set TEXT_OFFSET to 0x0 in preparation for removing it entirely
arm64: lib: Consistently enable crc32 extension
arm64/mm: Use phys_to_page() to access pgtable memory
arm64: smp: Make cpus_stuck_in_kernel static
arm64: entry: remove unneeded semicolon in el1_sync_handler()
arm64/kernel: vmlinux.lds: drop redundant discard/keep macros
arm64: drop GZFLAGS definition and export
arm64: kexec_file: Avoid temp buffer for RNG seed
arm64: rename stext to primary_entry
Perf PMU driver updates
(Tang Bin and others)
* for-next/perf:
pmu/smmuv3: Clear IRQ affinity hint on device removal
drivers/perf: hisi: Permit modular builds of HiSilicon uncore drivers
drivers/perf: hisi: Fix typo in events attribute array
drivers/perf: arm_spe_pmu: Avoid duplicate printouts
drivers/perf: arm_dsu_pmu: Avoid duplicate printouts
Pointer authentication updates and support for vmcoreinfo
(Amit Daniel Kachhap and Mark Rutland)
* for-next/ptr-auth:
Documentation/vmcoreinfo: Add documentation for 'KERNELPACMASK'
arm64/crash_core: Export KERNELPACMASK in vmcoreinfo
arm64: simplify ptrauth initialization
arm64: remove ptrauth_keys_install_kernel sync arg
SDEI cleanup and non-critical fixes
(James Morse and others)
* for-next/sdei:
firmware: arm_sdei: Document the motivation behind these set_fs() calls
firmware: arm_sdei: remove unused interfaces
firmware: arm_sdei: Put the SDEI table after using it
firmware: arm_sdei: Drop check for /firmware/ node and always register driver
SMCCC updates and refactoring
(Sudeep Holla)
* for-next/smccc:
firmware: smccc: Fix missing prototype warning for arm_smccc_version_init
firmware: smccc: Add function to fetch SMCCC version
firmware: smccc: Refactor SMCCC specific bits into separate file
firmware: smccc: Drop smccc_version enum and use ARM_SMCCC_VERSION_1_x instead
firmware: smccc: Add the definition for SMCCCv1.2 version/error codes
firmware: smccc: Update link to latest SMCCC specification
firmware: smccc: Add HAVE_ARM_SMCCC_DISCOVERY to identify SMCCC v1.1 and above
vDSO cleanup and non-critical fixes
(Mark Rutland and Vincenzo Frascino)
* for-next/vdso:
arm64: vdso: Add --eh-frame-hdr to ldflags
arm64: vdso: use consistent 'map' nomenclature
arm64: vdso: use consistent 'abi' nomenclature
arm64: vdso: simplify arch_vdso_type ifdeffery
arm64: vdso: remove aarch32_vdso_pages[]
arm64: vdso: Add '-Bsymbolic' to ldflags
Having __load_guest_stage2 in kvm_hyp.h is quickly going to trigger
a circular include problem. In order to avoid this, let's move
it to kvm_mmu.h, where it will be a better fit anyway.
In the process, drop the __hyp_text annotation, which doesn't help
as the function is marked as __always_inline.
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
With ARMv8.5-GTG, the hardware (or more likely a hypervisor) can
advertise the supported Stage-2 page sizes.
Let's check this at boot time.
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Commit f2ae97062a ("firmware: smccc: Refactor SMCCC specific bits into
separate file") introduced the following build warning:
drivers/firmware/smccc/smccc.c:14:13: warning: no previous prototype for
function 'arm_smccc_version_init' [-Wmissing-prototypes]
void __init arm_smccc_version_init(u32 version, enum arm_smccc_conduit conduit)
^~~~~~~~~~~~~~~~~~~~~~
Fix the same by adding the missing prototype in arm-smccc.h
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20200521110836.57252-1-sudeep.holla@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Daniel reports that the .cfi_startproc is misplaced for the sigreturn
trampoline, which causes LLVM's unwinder to misbehave:
| I run into this with LLVM’s unwinder.
| This combination was always broken.
This prompted Dave to question our use of CFI directives more generally,
and I ended up going down a rabbit hole trying to figure out how this
very poorly documented stuff gets used.
Move the CFI directives so that the "mysterious NOP" is included in
the .cfi_{start,end}proc block and add a bunch of comments so that I
can save myself another headache in future.
Cc: Tamas Zsoldos <tamas.zsoldos@arm.com>
Reported-by: Dave Martin <dave.martin@arm.com>
Reported-by: Daniel Kiss <daniel.kiss@arm.com>
Tested-by: Daniel Kiss <daniel.kiss@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
For better or worse, GDB relies on the exact instruction sequence in the
VDSO sigreturn trampoline in order to unwind from signals correctly.
Commit c91db232da ("arm64: vdso: Convert to modern assembler annotations")
unfortunately added a BTI C instruction to the start of __kernel_rt_sigreturn,
which breaks this check. Thankfully, it's also not required, since the
trampoline is called from a RET instruction when returning from the signal
handler
Remove the unnecessary BTI C instruction from __kernel_rt_sigreturn,
and do the same for the 32-bit VDSO as well for good measure.
Cc: Daniel Kiss <daniel.kiss@arm.com>
Cc: Tamas Zsoldos <tamas.zsoldos@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Fixes: c91db232da ("arm64: vdso: Convert to modern assembler annotations")
Signed-off-by: Will Deacon <will@kernel.org>
In order to add newer SMCCC v1.1+ functionality and to avoid cluttering
PSCI firmware driver with SMCCC bits, let us move the SMCCC specific
details under drivers/firmware/smccc/smccc.c
We can also drop conduit and smccc_version from psci_operations structure
as SMCCC was the sole user and now it maintains those.
No functionality change in this patch though.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Etienne Carriere <etienne.carriere@st.com>
Reviewed-by: Etienne Carriere <etienne.carriere@st.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200518091222.27467-6-sudeep.holla@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
SMCCC v1.0 lacked discoverability of version and features. To accelerate
adoption of few mitigations and protect systems more rapidly from various
vulnerability, PSCI v1.0 was updated to add SMCCC discovery mechanism
though the PSCI firmware implementation of PSCI_FEATURES(SMCCC_VERSION)
which returns success on firmware compliant to SMCCC v1.1 and above.
This inturn makes SMCCC v1.1 and above dependent on ARM_PSCI_FW for
backward compatibility. Let us introduce a new hidden config for the
same to build more features on top of SMCCC v1.1 and above.
While at it, also sort alphabetically the psci entry.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Etienne Carriere <etienne.carriere@st.com>
Reviewed-by: Etienne Carriere <etienne.carriere@st.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200518091222.27467-2-sudeep.holla@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Currently when trying to remove the SMMUv3 PMU module we get a
WARN_ON_ONCE from free_irq(), because the affinity hint set during probe
hasn't been properly cleared.
[ 238.878383] WARNING: CPU: 0 PID: 175 at kernel/irq/manage.c:1744 free_irq+0x324/0x358
...
[ 238.897263] Call trace:
[ 238.897998] free_irq+0x324/0x358
[ 238.898792] devm_irq_release+0x18/0x28
[ 238.899189] release_nodes+0x1b0/0x228
[ 238.899984] devres_release_all+0x38/0x60
[ 238.900779] device_release_driver_internal+0x10c/0x1d0
[ 238.901574] driver_detach+0x50/0xe0
[ 238.902368] bus_remove_driver+0x5c/0xd8
[ 238.903448] driver_unregister+0x30/0x60
[ 238.903958] platform_driver_unregister+0x14/0x20
[ 238.905075] arm_smmu_pmu_exit+0x1c/0xecc [arm_smmuv3_pmu]
[ 238.905547] __arm64_sys_delete_module+0x14c/0x260
[ 238.906342] el0_svc_common.constprop.0+0x74/0x178
[ 238.907355] do_el0_svc+0x24/0x90
[ 238.907932] el0_sync_handler+0x11c/0x198
[ 238.908979] el0_sync+0x158/0x180
Just like the other perf drivers, clear the affinity hint before
releasing the device.
Fixes: 7d839b4b9e ("perf/smmuv3: Add arm64 smmuv3 pmu driver")
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/r/20200422084805.237738-1-jean-philippe@linaro.org
Signed-off-by: Will Deacon <will@kernel.org>
A new kgdb feature will soon land (kgdb_earlycon) that lets us run
kgdb much earlier. In order for everything to work properly it's
important that the break hook is setup by the time we process
"kgdbwait".
Right now the break hook is setup in debug_traps_init() and that's
called from arch_initcall(). That's a bit too late since
kgdb_earlycon really needs things to be setup by the time the system
calls dbg_late_init().
We could fix this by adding call_break_hook() into early_brk64() and
that works fine. However, it's a little ugly. Instead, let's just
add a call to debug_traps_init() straight from trap_init(). There's
already a documented dependency between trap_init() and
debug_traps_init() and this makes the dependency more obvious rather
than just relying on a comment.
NOTE: this solution isn't early enough to let us select the
"ARCH_HAS_EARLY_DEBUG" KConfig option that is introduced by the
kgdb_earlycon patch series. That would only be set if we could do
breakpoints when early params are parsed. This patch only enables
"late early" breakpoints, AKA breakpoints when dbg_late_init() is
called. It's expected that this should be fine for most people.
It should also be noted that if you crash you can still end up in kgdb
earlier than debug_traps_init(). Since you don't need breakpoints to
debug a crash that's fine.
Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200513160501.1.I0b5edf030cc6ebef6ab4829f8867cdaea42485d8@changeid
Signed-off-by: Will Deacon <will@kernel.org>
The Shadow Call Stack pointer is held in x18, so update the ftrace
entry comment to indicate that it cannot be safely clobbered.
Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Defining static shadow call stacks is not architecture-specific, so move
the DEFINE_SCS() macro into the core header file.
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
asm/scs.h is no longer needed by the core code, so remove a redundant
header inclusion and update the stale Kconfig text.
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
There is nothing architecture-specific about scs_overflow_check() as
it's just a trivial wrapper around scs_corrupted().
For parity with task_stack_end_corrupted(), rename scs_corrupted() to
task_scs_end_corrupted() and call it from schedule_debug() when
CONFIG_SCHED_STACK_END_CHECK_is enabled, which better reflects its
purpose as a debug feature to catch inadvertent overflow of the SCS.
Finally, remove the unused scs_overflow_check() function entirely.
This has absolutely no impact on architectures that do not support SCS
(currently arm64 only).
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
x18 holds the SCS stack pointer value, so introduce a register alias to
make this easier to read in assembly code.
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
There's no need to perform the shadow stack page accounting independently
of the lifetime of the underlying allocation, so call the accounting code
from the {alloc,free}() functions and simplify the code in the process.
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
