diff options
| author | Kalesh Singh <kaleshsingh@google.com> | 2022-07-26 00:37:40 -0700 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2022-07-26 10:49:05 +0100 |
| commit | 548ec3336f323db56260b312c232ab37285f0284 (patch) | |
| tree | 5df07e5749b888bc368e4b078c5801f1260c5188 | |
| parent | 051ece6758cc10c2a6f1700ffe86d23fbb0b2553 (diff) | |
KVM: arm64: On stack overflow switch to hyp overflow_stack
On hyp stack overflow switch to 16-byte aligned secondary stack.
This provides us stack space to better handle overflows; and is
used in a subsequent patch to dump the hypervisor stacktrace.
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220726073750.3219117-8-kaleshsingh@google.com
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/host.S | 9 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/stacktrace.c | 11 |
3 files changed, 14 insertions, 8 deletions
diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile index f9fe4dc21b1f..524e7dad5739 100644 --- a/arch/arm64/kvm/hyp/nvhe/Makefile +++ b/arch/arm64/kvm/hyp/nvhe/Makefile @@ -14,7 +14,7 @@ lib-objs := $(addprefix ../../../lib/, $(lib-objs)) obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o \ hyp-main.o hyp-smp.o psci-relay.o early_alloc.o page_alloc.o \ - cache.o setup.o mm.o mem_protect.o sys_regs.o pkvm.o + cache.o setup.o mm.o mem_protect.o sys_regs.o pkvm.o stacktrace.o obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \ ../fpsimd.o ../hyp-entry.o ../exception.o ../pgtable.o obj-$(CONFIG_DEBUG_LIST) += list_debug.o diff --git a/arch/arm64/kvm/hyp/nvhe/host.S b/arch/arm64/kvm/hyp/nvhe/host.S index ea6a397b64a6..b6c0188c4b35 100644 --- a/arch/arm64/kvm/hyp/nvhe/host.S +++ b/arch/arm64/kvm/hyp/nvhe/host.S @@ -177,13 +177,8 @@ SYM_FUNC_END(__host_hvc) b hyp_panic .L__hyp_sp_overflow\@: - /* - * Reset SP to the top of the stack, to allow handling the hyp_panic. - * This corrupts the stack but is ok, since we won't be attempting - * any unwinding here. - */ - ldr_this_cpu x0, kvm_init_params + NVHE_INIT_STACK_HYP_VA, x1 - mov sp, x0 + /* Switch to the overflow stack */ + adr_this_cpu sp, overflow_stack + OVERFLOW_STACK_SIZE, x0 b hyp_panic_bad_stack ASM_BUG() diff --git a/arch/arm64/kvm/hyp/nvhe/stacktrace.c b/arch/arm64/kvm/hyp/nvhe/stacktrace.c new file mode 100644 index 000000000000..a3d5b34e1249 --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/stacktrace.c @@ -0,0 +1,11 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * KVM nVHE hypervisor stack tracing support. + * + * Copyright (C) 2022 Google LLC + */ +#include <asm/memory.h> +#include <asm/percpu.h> + +DEFINE_PER_CPU(unsigned long [OVERFLOW_STACK_SIZE/sizeof(long)], overflow_stack) + __aligned(16); |