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git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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39bc88e5e3
When the TTBR0 PAN feature is enabled, the kernel entry points need to disable access to TTBR0_EL1. The PAN status of the interrupted context is stored as part of the saved pstate, reusing the PSR_PAN_BIT (22). Restoring access to TTBR0_EL1 is done on exception return if returning to user or returning to a context where PAN was disabled. Context switching via switch_mm() must defer the update of TTBR0_EL1 until a return to user or an explicit uaccess_enable() call. Special care needs to be taken for two cases where TTBR0_EL1 is set outside the normal kernel context switch operation: EFI run-time services (via efi_set_pgd) and CPU suspend (via cpu_(un)install_idmap). Code has been added to avoid deferred TTBR0_EL1 switching as in switch_mm() and restore the reserved TTBR0_EL1 when uninstalling the special TTBR0_EL1. User cache maintenance (user_cache_maint_handler and __flush_cache_user_range) needs the TTBR0_EL1 re-instated since the operations are performed by user virtual address. This patch also removes a stale comment on the switch_mm() function. Cc: Will Deacon <will.deacon@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Kees Cook <keescook@chromium.org> Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> |
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| probes | ||
| vdso | ||
| .gitignore | ||
| acpi.c | ||
| acpi_numa.c | ||
| acpi_parking_protocol.c | ||
| alternative.c | ||
| arm64ksyms.c | ||
| armv8_deprecated.c | ||
| asm-offsets.c | ||
| cacheinfo.c | ||
| cpu-reset.h | ||
| cpu-reset.S | ||
| cpu_errata.c | ||
| cpu_ops.c | ||
| cpufeature.c | ||
| cpuidle.c | ||
| cpuinfo.c | ||
| debug-monitors.c | ||
| efi-entry.S | ||
| efi.c | ||
| entry-fpsimd.S | ||
| entry-ftrace.S | ||
| entry.S | ||
| entry32.S | ||
| fpsimd.c | ||
| ftrace.c | ||
| head.S | ||
| hibernate-asm.S | ||
| hibernate.c | ||
| hw_breakpoint.c | ||
| hyp-stub.S | ||
| image.h | ||
| insn.c | ||
| io.c | ||
| irq.c | ||
| jump_label.c | ||
| kaslr.c | ||
| kgdb.c | ||
| kuser32.S | ||
| machine_kexec.c | ||
| Makefile | ||
| module-plts.c | ||
| module.c | ||
| module.lds | ||
| paravirt.c | ||
| pci.c | ||
| perf_callchain.c | ||
| perf_event.c | ||
| perf_regs.c | ||
| process.c | ||
| psci.c | ||
| ptrace.c | ||
| relocate_kernel.S | ||
| return_address.c | ||
| setup.c | ||
| signal.c | ||
| signal32.c | ||
| sleep.S | ||
| smccc-call.S | ||
| smp.c | ||
| smp_spin_table.c | ||
| stacktrace.c | ||
| suspend.c | ||
| sys.c | ||
| sys32.c | ||
| sys_compat.c | ||
| time.c | ||
| topology.c | ||
| trace-events-emulation.h | ||
| traps.c | ||
| vdso.c | ||
| vmlinux.lds.S | ||