On Wed, Sep 07, 2022 at 04:50:38PM +1000, Michael Ellerman wrote: > As reported[1] by Nathan, the recently added plpks driver will crash if > it's built into the kernel and booted on a non-pseries machine, eg > powernv: > > kernel BUG at arch/powerpc/kernel/syscall.c:39! > Oops: Exception in kernel mode, sig: 5 [#1] > LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV > ... > NIP system_call_exception+0x90/0x3d0 > LR system_call_common+0xec/0x250 > Call Trace: > 0xc0000000035c3e10 (unreliable) > system_call_common+0xec/0x250 > --- interrupt: c00 at plpar_hcall+0x38/0x60 > NIP: c0000000000e4300 LR: c00000000202945c CTR: 0000000000000000 > REGS: c0000000035c3e80 TRAP: 0c00 Not tainted (6.0.0-rc4) > MSR: 9000000002009033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE> CR: 28000284 XER: > 00000000 > ... > NIP plpar_hcall+0x38/0x60 > LR pseries_plpks_init+0x64/0x23c > --- interrupt: c00 > > On powernv Linux is the hypervisor, so a hypercall just ends up going to > the syscall path, which BUGs if the syscall (hypercall) didn't come from > userspace. > > The fix is simply to not probe the plpks driver on non-pseries machines. > > [1] > https://lore.kernel.org/linuxppc-dev/Yxe06fbq18Wv9y3W@dev-arch.thelio-3990X/ > > Fixes: 2454a7af0f2a ("powerpc/pseries: define driver for Platform KeyStore") > Reported-by: Nathan Chancellor <nat...@kernel.org> > Signed-off-by: Michael Ellerman <m...@ellerman.id.au>
Tested-by: Nathan Chancellor <nat...@kernel.org> Thanks! > --- > arch/powerpc/platforms/pseries/plpks.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/platforms/pseries/plpks.c > b/arch/powerpc/platforms/pseries/plpks.c > index 52aaa2894606..f4b5b5a64db3 100644 > --- a/arch/powerpc/platforms/pseries/plpks.c > +++ b/arch/powerpc/platforms/pseries/plpks.c > @@ -17,6 +17,7 @@ > #include <linux/string.h> > #include <linux/types.h> > #include <asm/hvcall.h> > +#include <asm/machdep.h> > > #include "plpks.h" > > @@ -457,4 +458,4 @@ static __init int pseries_plpks_init(void) > > return rc; > } > -arch_initcall(pseries_plpks_init); > +machine_arch_initcall(pseries, pseries_plpks_init); > -- > 2.37.2 >
