TencentOS-kernel/include
Daniel Thompson 0faaef8771 kgdb: Fix spurious true from in_dbg_master()
[ Upstream commit 3fec4aecb311995189217e64d725cfe84a568de3 ]

Currently there is a small window where a badly timed migration could
cause in_dbg_master() to spuriously return true. Specifically if we
migrate to a new core after reading the processor id and the previous
core takes a breakpoint then we will evaluate true if we read
kgdb_active before we get the IPI to bring us to halt.

Fix this by checking irqs_disabled() first. Interrupts are always
disabled when we are executing the kgdb trap so this is an acceptable
prerequisite. This also allows us to replace raw_smp_processor_id()
with smp_processor_id() since the short circuit logic will prevent
warnings from PREEMPT_DEBUG.

Fixes: dcc7871128e9 ("kgdb: core changes to support kdb")
Suggested-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200506164223.2875760-1-daniel.thompson@linaro.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:29:29 +08:00
..
acpi x86: ACPI: fix CPU hotplug deadlock 2021-03-16 16:26:37 +08:00
asm-generic bpf: Support llvm-objcopy for vmlinux BTF 2021-03-16 16:28:55 +08:00
clocksource Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
crypto Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
drm drm/bridge: analogix_dp: Split bind() into probe() and real bind() 2021-03-16 16:27:24 +08:00
dt-bindings Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
keys KEYS: Don't write out to userspace while holding key semaphore 2021-03-16 16:26:42 +08:00
kvm Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
linux kgdb: Fix spurious true from in_dbg_master() 2021-03-16 16:29:29 +08:00
math-emu Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
media media: rc: add keymap for Videostrong KII Pro 2021-03-16 16:25:54 +08:00
misc Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
net dccp: Fix possible memleak in dccp_init and dccp_fini 2021-03-16 16:29:07 +08:00
pcmcia Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
ras Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
rdma RDMA/core: Fix double destruction of uobject 2021-03-16 16:28:36 +08:00
scsi Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
soc Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
sound ALSA: hda: Manage concurrent reg access more properly 2021-03-16 16:28:13 +08:00
target scsi: target: fix hang when multiple threads try to destroy the same iscsi session 2021-03-16 16:26:27 +08:00
trace rxrpc: Trace discarded ACKs 2021-03-16 16:28:21 +08:00
uapi x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exit 2021-03-16 16:29:22 +08:00
vdso Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
video Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
xen Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00