[PATCH V2 5/9] arm64: exception: handle instruction abort at current EL
From: Marc Zyngier <hidden>
Date: 2016-04-06 15:36:53
Also in:
linux-acpi, linux-efi, lkml
On 06/04/16 16:12, Tyler Baicar wrote:
quoted hunk ↗ jump to hunk
Add a handler for instruction aborts at the current EL (ESR_ELx_EC_IABT_CUR) so they are no longer handled in el1_inv. This allows firmware first handling for possible SEA (Synchronous External Abort) caused instruction abort at current EL. Signed-off-by: Tyler Baicar <redacted> Signed-off-by: Naveen Kaje <redacted> --- arch/arm64/kernel/entry.S | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+)diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 12e8d2b..f257856 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S@@ -336,6 +336,8 @@ el1_sync: lsr x24, x1, #ESR_ELx_EC_SHIFT // exception class cmp x24, #ESR_ELx_EC_DABT_CUR // data abort in EL1 b.eq el1_da + cmp x24, #ESR_ELx_EC_IABT_CUR // instruction abort in EL1 + b.eq el1_ia cmp x24, #ESR_ELx_EC_SYS64 // configurable trap b.eq el1_undef cmp x24, #ESR_ELx_EC_SP_ALIGN // stack alignment exception@@ -363,6 +365,23 @@ el1_da: // disable interrupts before pulling preserved data off the stack disable_irq kernel_exit 1 +el1_ia: + /* + * Instruction abort handling + */ + mrs x0, far_el1 + enable_dbg + // re-enable interrupts if they were enabled in the aborted context + tbnz x23, #7, 1f // PSR_I_BIT + enable_irq +1: + orr x1, x1, #1 << 24 // use reserved ISS bit for instruction aborts + mov x2, sp // struct pt_regs + bl do_mem_abort + + // disable interrupts before pulling preserved data off the stack + disable_irq + kernel_exit 1 el1_sp_pc: /* * Stack or PC alignment exception handling
What happens if you were running at EL2 when this faults gets injected? It looks like KVM needs something similar, doesn't it? Thanks, M. -- Jazz is not dead. It just smells funny...