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| author | Marc Zyngier <marc.zyngier@arm.com> | 2018-09-27 19:15:33 +0300 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2018-10-01 15:36:03 +0300 |
| commit | 32a3e635fb0ecc1b197d54f710e76c6481cf19f0 (patch) | |
| tree | abcec37734e52a8c3fd693c3631ba8f7a24732ef /arch/arm64/kernel/traps.c | |
| parent | 50de013d22e4e112d7b0778a0e7d032f16c46778 (diff) | |
| download | linux-32a3e635fb0ecc1b197d54f710e76c6481cf19f0.tar.xz | |
arm64: compat: Add CNTFRQ trap handler
Just like CNTVCT, we need to handle userspace trapping into the
kernel if we're decided that the timer wasn't fit for purpose...
64bit userspace is already dealt with, but we're missing the
equivalent compat handling.
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/kernel/traps.c')
| -rw-r--r-- | arch/arm64/kernel/traps.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 3602b900ff1c..58134a97928f 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -625,7 +625,20 @@ static void arm64_compat_skip_faulting_instruction(struct pt_regs *regs, arm64_skip_faulting_instruction(regs, sz); } +static void compat_cntfrq_read_handler(unsigned int esr, struct pt_regs *regs) +{ + int reg = (esr & ESR_ELx_CP15_32_ISS_RT_MASK) >> ESR_ELx_CP15_32_ISS_RT_SHIFT; + + pt_regs_write_reg(regs, reg, arch_timer_get_rate()); + arm64_compat_skip_faulting_instruction(regs, 4); +} + static struct sys64_hook cp15_32_hooks[] = { + { + .esr_mask = ESR_ELx_CP15_32_ISS_SYS_MASK, + .esr_val = ESR_ELx_CP15_32_ISS_SYS_CNTFRQ, + .handler = compat_cntfrq_read_handler, + }, {}, }; |