Message ID | 20210518094725.7701-17-will@kernel.org (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | Add support for 32-bit tasks on asymmetric AArch32 systems | expand |
On Tue, May 18, 2021 at 10:47:20AM +0100, Will Deacon wrote: > Provide an implementation of task_cpu_possible_mask() so that we can > prevent 64-bit-only cores being added to the 'cpus_mask' for compat > tasks on systems with mismatched 32-bit support at EL0, > > Signed-off-by: Will Deacon <will@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h index d3cef9133539..bb9b7510f334 100644 --- a/arch/arm64/include/asm/mmu_context.h +++ b/arch/arm64/include/asm/mmu_context.h @@ -231,6 +231,19 @@ switch_mm(struct mm_struct *prev, struct mm_struct *next, update_saved_ttbr0(tsk, next); } +static inline const struct cpumask * +task_cpu_possible_mask(struct task_struct *p) +{ + if (!static_branch_unlikely(&arm64_mismatched_32bit_el0)) + return cpu_possible_mask; + + if (!is_compat_thread(task_thread_info(p))) + return cpu_possible_mask; + + return system_32bit_el0_cpumask(); +} +#define task_cpu_possible_mask task_cpu_possible_mask + void verify_cpu_asid_bits(void); void post_ttbr_update_workaround(void);
Provide an implementation of task_cpu_possible_mask() so that we can prevent 64-bit-only cores being added to the 'cpus_mask' for compat tasks on systems with mismatched 32-bit support at EL0, Signed-off-by: Will Deacon <will@kernel.org> --- arch/arm64/include/asm/mmu_context.h | 13 +++++++++++++ 1 file changed, 13 insertions(+)