BMC/Intel-BMC/linux.git/arch/arm64/include, branch dev-5.4

arm64: Workaround circular dependency in pointer_auth.h

2020-08-07T07:34:01+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

2020-08-05T07:59:48+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

2020-08-05T07:59:48+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

2020-07-22T07:33:16+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

2020-07-22T07:33:16+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

2020-07-22T07:33:16+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/alternatives: use subsections for replacement sequences

2020-07-22T07:32:53+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

arm64: arch_timer: Allow an workaround descriptor to disable compat vdso

2020-07-22T07:32:50+00:00

commit c1fbec4ac0d701f350a581941d35643d5a9cd184 upstream. As we are about to disable the vdso for compat tasks in some circumstances, let's allow a workaround descriptor to express exactly that. Signed-off-by: Marc Zyngier Acked-by: Mark Rutland Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200706163802.1836732-3-maz@kernel.org Signed-off-by: Will Deacon Signed-off-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman

arm64: Introduce a way to disable the 32bit vdso

2020-07-22T07:32:50+00:00

commit 97884ca8c2925d14c32188e865069f21378b4b4f upstream. [this is a redesign rather than a backport] We have a class of errata (grouped under the ARM64_WORKAROUND_1418040 banner) that force the trapping of counter access from 32bit EL0. We would normally disable the whole vdso for such defect, except that it would disable it for 64bit userspace as well, which is a shame. Instead, add a new vdso_clock_mode, which signals that the vdso isn't usable for compat tasks. This gets checked in the new vdso_clocksource_ok() helper, now provided for the 32bit vdso. Signed-off-by: Marc Zyngier Acked-by: Mark Rutland Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200706163802.1836732-2-maz@kernel.org Signed-off-by: Will Deacon Signed-off-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman

KVM: arm64: Annotate hyp NMI-related functions as __always_inline

2020-07-16T06:16:43+00:00

commit 7733306bd593c737c63110175da6c35b4b8bb32c upstream. The "inline" keyword is a hint for the compiler to inline a function. The functions system_uses_irq_prio_masking() and gic_write_pmr() are used by the code running at EL2 on a non-VHE system, so mark them as __always_inline to make sure they'll always be part of the .hyp.text section. This fixes the following splat when trying to run a VM: [ 47.625273] Kernel panic - not syncing: HYP panic: [ 47.625273] PS:a00003c9 PC:0000ca0b42049fc4 ESR:86000006 [ 47.625273] FAR:0000ca0b42049fc4 HPFAR:0000000010001000 PAR:0000000000000000 [ 47.625273] VCPU:0000000000000000 [ 47.647261] CPU: 1 PID: 217 Comm: kvm-vcpu-0 Not tainted 5.8.0-rc1-ARCH+ #61 [ 47.654508] Hardware name: Globalscale Marvell ESPRESSOBin Board (DT) [ 47.661139] Call trace: [ 47.663659] dump_backtrace+0x0/0x1cc [ 47.667413] show_stack+0x18/0x24 [ 47.670822] dump_stack+0xb8/0x108 [ 47.674312] panic+0x124/0x2f4 [ 47.677446] panic+0x0/0x2f4 [ 47.680407] SMP: stopping secondary CPUs [ 47.684439] Kernel Offset: disabled [ 47.688018] CPU features: 0x240402,20002008 [ 47.692318] Memory Limit: none [ 47.695465] ---[ end Kernel panic - not syncing: HYP panic: [ 47.695465] PS:a00003c9 PC:0000ca0b42049fc4 ESR:86000006 [ 47.695465] FAR:0000ca0b42049fc4 HPFAR:0000000010001000 PAR:0000000000000000 [ 47.695465] VCPU:0000000000000000 ]--- The instruction abort was caused by the code running at EL2 trying to fetch an instruction which wasn't mapped in the EL2 translation tables. Using objdump showed the two functions as separate symbols in the .text section. Fixes: 85738e05dc38 ("arm64: kvm: Unmask PMR before entering guest") Cc: stable@vger.kernel.org Signed-off-by: Alexandru Elisei Signed-off-by: Marc Zyngier Acked-by: James Morse Link: https://lore.kernel.org/r/20200618171254.1596055-1-alexandru.elisei@arm.com Signed-off-by: Greg Kroah-Hartman