diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2020-10-27 10:15:05 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2020-10-27 23:15:23 +0100 |
| commit | 2a9baf5ad4884108b3c6d56a50e8105ccf8a4ee7 (patch) | |
| tree | bc9ec3a80992bfac570f35708959deb34210848b /arch/x86/kernel/smp.c | |
| parent | ed8780e3f2ecc82645342d070c6b4e530532e680 (diff) | |
x86/debug: Fix BTF handling
The SDM states that #DB clears DEBUGCTLMSR_BTF, this means that when the
bit is set for userspace (TIF_BLOCKSTEP) and a kernel #DB happens first,
the BTF bit meant for userspace execution is lost.
Have the kernel #DB handler restore the BTF bit when it was requested
for userspace.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Kyle Huey <me@kylehuey.com>
Link: https://lore.kernel.org/r/20201027093607.956147736@infradead.org
Diffstat (limited to 'arch/x86/kernel/smp.c')
0 files changed, 0 insertions, 0 deletions