On Thu, Nov 01, 2018 at 09:18:02PM -0400, David Long wrote:
On 10/31/18 9:56 AM, David Long wrote:
From: "David A. Long" dave.long@linaro.org
V4.9 backport of spectre patches from Russell M. King's spectre branch. Patches not yet in upstream are excluded.
Marc Zyngier (2): ARM: KVM: invalidate BTB on guest exit for Cortex-A12/A17 ARM: KVM: invalidate icache on guest exit for Cortex-A15
Russell King (22): ARM: add more CPU part numbers for Cortex and Brahma B15 CPUs ARM: bugs: prepare processor bug infrastructure ARM: bugs: hook processor bug checking into SMP and suspend paths ARM: bugs: add support for per-processor bug checking ARM: spectre: add Kconfig symbol for CPUs vulnerable to Spectre ARM: spectre-v2: harden branch predictor on context switches ARM: spectre-v2: add Cortex A8 and A15 validation of the IBE bit ARM: spectre-v2: harden user aborts in kernel space ARM: spectre-v2: add firmware based hardening ARM: spectre-v2: warn about incorrect context switching functions ARM: spectre-v2: KVM: invalidate icache on guest exit for Brahma B15 ARM: KVM: Add SMCCC_ARCH_WORKAROUND_1 fast handling ARM: KVM: report support for SMCCC_ARCH_WORKAROUND_1 ARM: spectre-v1: add speculation barrier (csdb) macros ARM: spectre-v1: add array_index_mask_nospec() implementation ARM: spectre-v1: fix syscall entry ARM: signal: copy registers using __copy_from_user() ARM: vfp: use __copy_from_user() when restoring VFP state ARM: oabi-compat: copy semops using __copy_from_user() ARM: use __inttype() in get_user() ARM: spectre-v1: use get_user() for __get_user() ARM: spectre-v1: mitigate user accesses
arch/arm/include/asm/assembler.h | 12 ++ arch/arm/include/asm/barrier.h | 32 ++++++ arch/arm/include/asm/bugs.h | 6 +- arch/arm/include/asm/cp15.h | 3 + arch/arm/include/asm/cputype.h | 8 ++ arch/arm/include/asm/kvm_asm.h | 2 - arch/arm/include/asm/kvm_host.h | 14 ++- arch/arm/include/asm/kvm_mmu.h | 23 +++- arch/arm/include/asm/proc-fns.h | 4 + arch/arm/include/asm/system_misc.h | 15 +++ arch/arm/include/asm/thread_info.h | 4 +- arch/arm/include/asm/uaccess.h | 26 +++-- arch/arm/kernel/Makefile | 1 + arch/arm/kernel/bugs.c | 18 +++ arch/arm/kernel/entry-common.S | 18 ++- arch/arm/kernel/entry-header.S | 25 +++++ arch/arm/kernel/signal.c | 55 ++++----- arch/arm/kernel/smp.c | 4 + arch/arm/kernel/suspend.c | 2 + arch/arm/kernel/sys_oabi-compat.c | 8 +- arch/arm/kvm/hyp/hyp-entry.S | 110 +++++++++++++++++- arch/arm/lib/copy_from_user.S | 9 ++ arch/arm/mm/Kconfig | 23 ++++ arch/arm/mm/Makefile | 2 +- arch/arm/mm/fault.c | 3 + arch/arm/mm/proc-macros.S | 3 +- arch/arm/mm/proc-v7-2level.S | 6 - arch/arm/mm/proc-v7-bugs.c | 174 +++++++++++++++++++++++++++++ arch/arm/mm/proc-v7.S | 154 +++++++++++++++++++------ arch/arm/vfp/vfpmodule.c | 17 ++- 30 files changed, 674 insertions(+), 107 deletions(-) create mode 100644 arch/arm/kernel/bugs.c create mode 100644 arch/arm/mm/proc-v7-bugs.c
kvm-unit-test'ing of this results in a hypervisor panic that doesn't happen without the patches. This needs to be figured out before it is accepted into stable. Looks like a V2 will be needed. Clearly kernelci testing alone is not sufficient when dealing with kvm changes.
I've discovered in the last few days that kernelci boot testing is next to useless - it bases its pass/fail result on whether it gets to a shell prompt, which can happen even if the kernel hits a BUG() or warning that doesn't prevent the system getting to a shell prompt.
For example, see:
01:08:40.181846 [ 9.309984] Unable to handle kernel paging request at virtual address e7fddef0
which is the kernel hitting a BUG() in:
https://storage.kernelci.org/rmk/to-build/v4.16-38-g9fa10446d304/arm/multi_v...
and that results in a "pass" result for that boot test.
So, don't believe a "pass" result from kernelci at the moment, it's meaningless in determining whether anything has broken. The only way around this is to manually read each and every boot log, which is tedious, or run your own tests on local systems.
I've reported this to info@kernelci.org earlier this week, and am waiting for a response.