diff options
| author | Michael Neuling <mikey@neuling.org> | 2018-05-18 11:37:42 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2018-05-18 16:05:15 +1000 |
| commit | faf37c44a105f3608115785f17cbbf3500f8bc71 (patch) | |
| tree | 5d7a9292192cb0936af35357aa5f007640b95f85 /arch/powerpc/kernel/dt_cpu_ftrs.c | |
| parent | c1d2a31397ec51f0370f6bd17b19b39152c263cb (diff) | |
powerpc/64s: Clear PCR on boot
Clear the PCR (Processor Compatibility Register) on boot to ensure we
are not running in a compatibility mode.
We've seen this cause problems when a crash (and kdump) occurs while
running compat mode guests. The kdump kernel then runs with the PCR
set and causes problems. The symptom in the kdump kernel (also seen in
petitboot after fast-reboot) is early userspace programs taking
sigills on newer instructions (seen in libc).
Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: stable@vger.kernel.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/kernel/dt_cpu_ftrs.c')
| -rw-r--r-- | arch/powerpc/kernel/dt_cpu_ftrs.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/dt_cpu_ftrs.c b/arch/powerpc/kernel/dt_cpu_ftrs.c index 8ab51f6ca03a..c904477abaf3 100644 --- a/arch/powerpc/kernel/dt_cpu_ftrs.c +++ b/arch/powerpc/kernel/dt_cpu_ftrs.c @@ -101,6 +101,7 @@ static void __restore_cpu_cpufeatures(void) if (hv_mode) { mtspr(SPRN_LPID, 0); mtspr(SPRN_HFSCR, system_registers.hfscr); + mtspr(SPRN_PCR, 0); } mtspr(SPRN_FSCR, system_registers.fscr); |