| Message ID | 20220308135047.478297-5-npiggin@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | powerpc/rtas: various cleanups and improvements | expand |
On 08/03/2022, 14:50:37, Nicholas Piggin wrote: > Disable MSR[EE] in C code rather than asm. > > Signed-off-by: Nicholas Piggin <npiggin@gmail.com> FWIW, Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> > --- > arch/powerpc/kernel/rtas.c | 4 ++++ > arch/powerpc/kernel/rtas_entry.S | 17 +---------------- > 2 files changed, 5 insertions(+), 16 deletions(-) > > diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c > index 733e6ef36758..6b5892d6a56b 100644 > --- a/arch/powerpc/kernel/rtas.c > +++ b/arch/powerpc/kernel/rtas.c > @@ -49,6 +49,10 @@ void enter_rtas(unsigned long); > > static inline void do_enter_rtas(unsigned long args) > { > + BUG_ON(!irqs_disabled()); > + > + hard_irq_disable(); /* Ensure MSR[EE] is disabled on PPC64 */ > + > enter_rtas(args); > > srr_regs_clobbered(); /* rtas uses SRRs, invalidate */ > diff --git a/arch/powerpc/kernel/rtas_entry.S b/arch/powerpc/kernel/rtas_entry.S > index 6fa10eb49a9c..45fa661c2ff6 100644 > --- a/arch/powerpc/kernel/rtas_entry.S > +++ b/arch/powerpc/kernel/rtas_entry.S > @@ -24,8 +24,6 @@ _GLOBAL(enter_rtas) > lwz r4,RTASBASE(r4) > mfmsr r9 > stw r9,8(r1) > - LOAD_REG_IMMEDIATE(r0,MSR_KERNEL) > - mtmsr r0 /* disable interrupts so SRR0/1 don't get trashed */ > li r9,MSR_KERNEL & ~(MSR_IR|MSR_DR) > mtlr r6 > stw r1, THREAD + RTAS_SP(r2) > @@ -87,20 +85,7 @@ _GLOBAL(enter_rtas) > li r0,0 > mtcr r0 > > -#ifdef CONFIG_BUG > - /* There is no way it is acceptable to get here with interrupts enabled, > - * check it with the asm equivalent of WARN_ON > - */ > - lbz r0,PACAIRQSOFTMASK(r13) > -1: tdeqi r0,IRQS_ENABLED > - EMIT_WARN_ENTRY 1b,__FILE__,__LINE__,BUGFLAG_WARNING > -#endif > - > - /* Hard-disable interrupts */ > mfmsr r6 > - rldicl r7,r6,48,1 > - rotldi r7,r7,16 > - mtmsrd r7,1 > > /* Unfortunately, the stack pointer and the MSR are also clobbered, > * so they are saved in the PACA which allows us to restore > @@ -124,7 +109,7 @@ _GLOBAL(enter_rtas) > andc r6,r0,r9 > > __enter_rtas: > - sync /* disable interrupts so SRR0/1 */ > + sync /* disable RI so SRR0/1 */ > mtmsrd r0 /* don't get trashed */ > > LOAD_REG_ADDR(r4, rtas)
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c index 733e6ef36758..6b5892d6a56b 100644 --- a/arch/powerpc/kernel/rtas.c +++ b/arch/powerpc/kernel/rtas.c @@ -49,6 +49,10 @@ void enter_rtas(unsigned long); static inline void do_enter_rtas(unsigned long args) { + BUG_ON(!irqs_disabled()); + + hard_irq_disable(); /* Ensure MSR[EE] is disabled on PPC64 */ + enter_rtas(args); srr_regs_clobbered(); /* rtas uses SRRs, invalidate */ diff --git a/arch/powerpc/kernel/rtas_entry.S b/arch/powerpc/kernel/rtas_entry.S index 6fa10eb49a9c..45fa661c2ff6 100644 --- a/arch/powerpc/kernel/rtas_entry.S +++ b/arch/powerpc/kernel/rtas_entry.S @@ -24,8 +24,6 @@ _GLOBAL(enter_rtas) lwz r4,RTASBASE(r4) mfmsr r9 stw r9,8(r1) - LOAD_REG_IMMEDIATE(r0,MSR_KERNEL) - mtmsr r0 /* disable interrupts so SRR0/1 don't get trashed */ li r9,MSR_KERNEL & ~(MSR_IR|MSR_DR) mtlr r6 stw r1, THREAD + RTAS_SP(r2) @@ -87,20 +85,7 @@ _GLOBAL(enter_rtas) li r0,0 mtcr r0 -#ifdef CONFIG_BUG - /* There is no way it is acceptable to get here with interrupts enabled, - * check it with the asm equivalent of WARN_ON - */ - lbz r0,PACAIRQSOFTMASK(r13) -1: tdeqi r0,IRQS_ENABLED - EMIT_WARN_ENTRY 1b,__FILE__,__LINE__,BUGFLAG_WARNING -#endif - - /* Hard-disable interrupts */ mfmsr r6 - rldicl r7,r6,48,1 - rotldi r7,r7,16 - mtmsrd r7,1 /* Unfortunately, the stack pointer and the MSR are also clobbered, * so they are saved in the PACA which allows us to restore @@ -124,7 +109,7 @@ _GLOBAL(enter_rtas) andc r6,r0,r9 __enter_rtas: - sync /* disable interrupts so SRR0/1 */ + sync /* disable RI so SRR0/1 */ mtmsrd r0 /* don't get trashed */ LOAD_REG_ADDR(r4, rtas)
Disable MSR[EE] in C code rather than asm. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- arch/powerpc/kernel/rtas.c | 4 ++++ arch/powerpc/kernel/rtas_entry.S | 17 +---------------- 2 files changed, 5 insertions(+), 16 deletions(-)