kernel/git/stable/linux.git/arch/arm64/include, branch linux-5.7.y

KVM: Pass MMU notifier range flags to kvm_unmap_hva_range()

2020-08-26T09:42:24+00:00

commit fdfe7cbd58806522e799e2a50a15aee7f2cbb7b6 upstream. The 'flags' field of 'struct mmu_notifier_range' is used to indicate whether invalidate_range_{start,end}() are permitted to block. In the case of kvm_mmu_notifier_invalidate_range_start(), this field is not forwarded on to the architecture-specific implementation of kvm_unmap_hva_range() and therefore the backend cannot sensibly decide whether or not to block. Add an extra 'flags' parameter to kvm_unmap_hva_range() so that architectures are aware as to whether or not they are permitted to block. Cc: Cc: Marc Zyngier Cc: Suzuki K Poulose Cc: James Morse Signed-off-by: Will Deacon Message-Id: <20200811102725.7121-2-will@kernel.org> Signed-off-by: Paolo Bonzini Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

random: random.h should include archrandom.h, not the other way around

2020-08-07T07:33:11+00:00

commit 585524081ecdcde1c719e63916c514866d898217 upstream. This is hopefully the final piece of the crazy puzzle with random.h dependencies. And by "hopefully" I obviously mean "Linus is a hopeless optimist". Reported-and-tested-by: Daniel Díaz Acked-by: Guenter Roeck Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

arm64: Workaround circular dependency in pointer_auth.h

2020-08-07T07:33:11+00:00

With the backport of f227e3ec3b5c ("random32: update the net random state on interrupt and activity") and its associated fixes, the arm64 build explodes early: In file included from ../include/linux/smp.h:67, from ../include/linux/percpu.h:7, from ../include/linux/prandom.h:12, from ../include/linux/random.h:118, from ../arch/arm64/include/asm/pointer_auth.h:6, from ../arch/arm64/include/asm/processor.h:39, from ../include/linux/mutex.h:19, from ../include/linux/kernfs.h:12, from ../include/linux/sysfs.h:16, from ../include/linux/kobject.h:20, from ../include/linux/of.h:17, from ../include/linux/irqdomain.h:35, from ../include/linux/acpi.h:13, from ../include/acpi/apei.h:9, from ../include/acpi/ghes.h:5, from ../include/linux/arm_sdei.h:8, from ../arch/arm64/kernel/asm-offsets.c:10: ../arch/arm64/include/asm/smp.h:100:29: error: field ‘ptrauth_key’ has incomplete type This is due to struct ptrauth_keys_kernel not being defined before we transitively include asm/smp.h from linux/random.h. Paper over it by moving the inclusion of linux/random.h *after* the type has been defined. Signed-off-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman

arm64: csum: Fix handling of bad packets

2020-08-05T07:58:46+00:00

[ Upstream commit 05fb3dbda187bbd9cc1cd0e97e5d6595af570ac6 ] Although iph is expected to point to at least 20 bytes of valid memory, ihl may be bogus, for example on reception of a corrupt packet. If it happens to be less than 5, we really don't want to run away and dereference 16GB worth of memory until it wraps back to exactly zero... Fixes: 0e455d8e80aa ("arm64: Implement optimised IP checksum helpers") Reported-by: guodeqing Signed-off-by: Robin Murphy Signed-off-by: Will Deacon Signed-off-by: Sasha Levin

arm64/alternatives: move length validation inside the subsection

2020-08-05T07:58:46+00:00

[ Upstream commit 966a0acce2fca776391823381dba95c40e03c339 ] Commit f7b93d42945c ("arm64/alternatives: use subsections for replacement sequences") breaks LLVM's integrated assembler, because due to its one-pass design, it cannot compute instruction sequence lengths before the layout for the subsection has been finalized. This change fixes the build by moving the .org directives inside the subsection, so they are processed after the subsection layout is known. Fixes: f7b93d42945c ("arm64/alternatives: use subsections for replacement sequences") Signed-off-by: Sami Tolvanen Link: https://github.com/ClangBuiltLinux/linux/issues/1078 Link: https://lore.kernel.org/r/20200730153701.3892953-1-samitolvanen@google.com Signed-off-by: Will Deacon Signed-off-by: Sasha Levin

arm64: compat: Ensure upper 32 bits of x0 are zero on syscall return

2020-07-22T07:34:26+00:00

commit 15956689a0e60aa0c795174f3c310b60d8794235 upstream. Although we zero the upper bits of x0 on entry to the kernel from an AArch32 task, we do not clear them on the exception return path and can therefore expose 64-bit sign extended syscall return values to userspace via interfaces such as the 'perf_regs' ABI, which deal exclusively with 64-bit registers. Explicitly clear the upper 32 bits of x0 on return from a compat system call. Cc: Cc: Mark Rutland Cc: Keno Fischer Cc: Luis Machado Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

arm64: ptrace: Consistently use pseudo-singlestep exceptions

2020-07-22T07:34:25+00:00

commit ac2081cdc4d99c57f219c1a6171526e0fa0a6fff upstream. Although the arm64 single-step state machine can be fast-forwarded in cases where we wish to generate a SIGTRAP without actually executing an instruction, this has two major limitations outside of simply skipping an instruction due to emulation. 1. Stepping out of a ptrace signal stop into a signal handler where SIGTRAP is blocked. Fast-forwarding the stepping state machine in this case will result in a forced SIGTRAP, with the handler reset to SIG_DFL. 2. The hardware implicitly fast-forwards the state machine when executing an SVC instruction for issuing a system call. This can interact badly with subsequent ptrace stops signalled during the execution of the system call (e.g. SYSCALL_EXIT or seccomp traps), as they may corrupt the stepping state by updating the PSTATE for the tracee. Resolve both of these issues by injecting a pseudo-singlestep exception on entry to a signal handler and also on return to userspace following a system call. Cc: Cc: Mark Rutland Tested-by: Luis Machado Reported-by: Keno Fischer Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

arm64: ptrace: Override SPSR.SS when single-stepping is enabled

2020-07-22T07:34:25+00:00

commit 3a5a4366cecc25daa300b9a9174f7fdd352b9068 upstream. Luis reports that, when reverse debugging with GDB, single-step does not function as expected on arm64: | I've noticed, under very specific conditions, that a PTRACE_SINGLESTEP | request by GDB won't execute the underlying instruction. As a consequence, | the PC doesn't move, but we return a SIGTRAP just like we would for a | regular successful PTRACE_SINGLESTEP request. The underlying problem is that when the CPU register state is restored as part of a reverse step, the SPSR.SS bit is cleared and so the hardware single-step state can transition to the "active-pending" state, causing an unexpected step exception to be taken immediately if a step operation is attempted. In hindsight, we probably shouldn't have exposed SPSR.SS in the pstate accessible by the GPR regset, but it's a bit late for that now. Instead, simply prevent userspace from configuring the bit to a value which is inconsistent with the TIF_SINGLESTEP state for the task being traced. Cc: Cc: Mark Rutland Cc: Keno Fischer Link: https://lore.kernel.org/r/1eed6d69-d53d-9657-1fc9-c089be07f98c@linaro.org Reported-by: Luis Machado Tested-by: Luis Machado Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

arm64: Add MIDR value for KRYO4XX gold CPU cores

2020-07-22T07:34:02+00:00

[ Upstream commit dce4f2807f6920bb907eb4cd4f95e7f42d918bc6 ] Add MIDR value for KRYO4XX gold/big CPU cores which are used in Qualcomm Technologies, Inc. SoCs. This will be used to identify and apply erratum which are applicable for these CPU cores. Signed-off-by: Sai Prakash Ranjan Link: https://lore.kernel.org/r/9093fb82e22441076280ca1b729242ffde80c432.1593539394.git.saiprakash.ranjan@codeaurora.org Signed-off-by: Will Deacon Signed-off-by: Sasha Levin

arm64/alternatives: use subsections for replacement sequences

2020-07-22T07:34:00+00:00

[ Upstream commit f7b93d42945cc71e1346dd5ae07c59061d56745e ] When building very large kernels, the logic that emits replacement sequences for alternatives fails when relative branches are present in the code that is emitted into the .altinstr_replacement section and patched in at the original site and fixed up. The reason is that the linker will insert veneers if relative branches go out of range, and due to the relative distance of the .altinstr_replacement from the .text section where its branch targets usually live, veneers may be emitted at the end of the .altinstr_replacement section, with the relative branches in the sequence pointed at the veneers instead of the actual target. The alternatives patching logic will attempt to fix up the branch to point to its original target, which will be the veneer in this case, but given that the patch site is likely to be far away as well, it will be out of range and so patching will fail. There are other cases where these veneers are problematic, e.g., when the target of the branch is in .text while the patch site is in .init.text, in which case putting the replacement sequence inside .text may not help either. So let's use subsections to emit the replacement code as closely as possible to the patch site, to ensure that veneers are only likely to be emitted if they are required at the patch site as well, in which case they will be in range for the replacement sequence both before and after it is transported to the patch site. This will prevent alternative sequences in non-init code from being released from memory after boot, but this is tolerable given that the entire section is only 512 KB on an allyesconfig build (which weighs in at 500+ MB for the entire Image). Also, note that modules today carry the replacement sequences in non-init sections as well, and any of those that target init code will be emitted into init sections after this change. This fixes an early crash when booting an allyesconfig kernel on a system where any of the alternatives sequences containing relative branches are activated at boot (e.g., ARM64_HAS_PAN on TX2) Signed-off-by: Ard Biesheuvel Cc: Suzuki K Poulose Cc: James Morse Cc: Andre Przywara Cc: Dave P Martin Link: https://lore.kernel.org/r/20200630081921.13443-1-ardb@kernel.org Signed-off-by: Will Deacon Signed-off-by: Sasha Levin