lkml.org 
[lkml]   [2018]   [May]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] arm64: kvm: use -fno-jump-tables with clang
Date
Starting with LLVM r308050, clang generates a jump table with EL1
virtual addresses in __init_stage2_translation, which results in a
kernel panic when booting at EL2:

Kernel panic - not syncing: HYP panic:
PS:800003c9 PC:ffff0000089e6fd8 ESR:86000004
FAR:ffff0000089e6fd8 HPFAR:0000000009825000 PAR:0000000000000000
VCPU:000804fc20001221

CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.14.0-rc7-dirty #3
Hardware name: ARM Juno development board (r1) (DT)
Call trace:
[<ffff000008088ea4>] dump_backtrace+0x0/0x34c
[<ffff000008089208>] show_stack+0x18/0x20
[<ffff0000089c73ec>] dump_stack+0xc4/0xfc
[<ffff0000080c8e1c>] panic+0x138/0x2b4
[<ffff0000080c8ce4>] panic+0x0/0x2b4
SMP: stopping secondary CPUs
SMP: failed to stop secondary CPUs 0-3,5
Kernel Offset: disabled
CPU features: 0x002086
Memory Limit: none
---[ end Kernel panic - not syncing: HYP panic:
PS:800003c9 PC:ffff0000089e6fd8 ESR:86000004
FAR:ffff0000089e6fd8 HPFAR:0000000009825000 PAR:0000000000000000
VCPU:000804fc20001221

This change adds -fno-jump-tables to arm64/hyp to work around the
bug.

Suggested-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
---
arch/arm64/kvm/hyp/Makefile | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/arm64/kvm/hyp/Makefile b/arch/arm64/kvm/hyp/Makefile
index 4313f74753332..745b3255e7832 100644
--- a/arch/arm64/kvm/hyp/Makefile
+++ b/arch/arm64/kvm/hyp/Makefile
@@ -5,6 +5,10 @@

ccflags-y += -fno-stack-protector -DDISABLE_BRANCH_PROFILING

+ifeq ($(cc-name),clang)
+ccflags-y += -fno-jump-tables
+endif
+
KVM=../../../../virt/kvm

obj-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/hyp/vgic-v3-sr.o
--
2.17.0.441.gb46fe60e1d-goog
\
 
 \ /
  Last update: 2018-05-18 19:02    [W:0.156 / U:0.012 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site