diff options
| author | Marc Zyngier <maz@kernel.org> | 2022-06-30 17:04:53 +0100 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2022-07-01 15:22:51 +0100 |
| commit | b65e411d6cc2f12a728cabe66b930c63c527a340 (patch) | |
| tree | b6a307dc0e11c1201da9e3ed852b5d737dad30a6 /arch/arm64/kernel/head.S | |
| parent | 7ddb0c3df7881206dcd8339c8dabf0318a781f91 (diff) | |
arm64: Save state of HCR_EL2.E2H before switch to EL1
As we're about to switch the way E2H-stuck CPUs boot, save
the boot CPU E2H state as a flag tied to the boot mode
that can then be checked by the idreg override code.
This allows us to replace the is_kernel_in_hyp_mode() check
with a simple comparison with this state, even when running
at EL1. Note that this flag isn't saved in __boot_cpu_mode,
and is only kept in a register in the assembly code.
Use with caution.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220630160500.1536744-3-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/kernel/head.S')
| -rw-r--r-- | arch/arm64/kernel/head.S | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 6feac4ee105a..73eb7c96a245 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -457,6 +457,7 @@ SYM_FUNC_START_LOCAL(__primary_switched) bl kasan_early_init #endif mov x0, x22 // pass FDT address in x0 + mov x1, x20 // pass the full boot status bl init_feature_override // Parse cpu feature overrides mov x0, x20 bl finalise_el2 // Prefer VHE if possible @@ -479,8 +480,9 @@ SYM_FUNC_END(__primary_switched) * Since we cannot always rely on ERET synchronizing writes to sysregs (e.g. if * SCTLR_ELx.EOS is clear), we place an ISB prior to ERET. * - * Returns either BOOT_CPU_MODE_EL1 or BOOT_CPU_MODE_EL2 in w0 if - * booted in EL1 or EL2 respectively. + * Returns either BOOT_CPU_MODE_EL1 or BOOT_CPU_MODE_EL2 in x0 if + * booted in EL1 or EL2 respectively, with the top 32 bits containing + * potential context flags. These flags are *not* stored in __boot_cpu_mode. */ SYM_FUNC_START(init_kernel_el) mrs x0, CurrentEL @@ -545,6 +547,7 @@ __cpu_stick_to_vhe: mov x0, #HVC_FINALISE_EL2 hvc #0 mov x0, #BOOT_CPU_MODE_EL2 + orr x0, x0, #BOOT_CPU_FLAG_E2H ret SYM_FUNC_END(init_kernel_el) |