Re: [PATCH 1/3] powerpc/64s: Mask NIP before checking against SRR0

2021-12-26 Thread Michael Ellerman
On Wed, 22 Dec 2021 00:50:59 +1100, Michael Ellerman wrote: > When CONFIG_PPC_RFI_SRR_DEBUG=y we check that NIP and SRR0 match when > returning from interrupts. This can trigger falsely if NIP has either of > its two low bits set via sigreturn or ptrace, while SRR0 has its low two > bits masked in

Re: [PATCH 1/3] powerpc/64s: Mask NIP before checking against SRR0

2021-12-22 Thread Sachin Sant
> On 21-Dec-2021, at 7:20 PM, Michael Ellerman wrote: > > When CONFIG_PPC_RFI_SRR_DEBUG=y we check that NIP and SRR0 match when > returning from interrupts. This can trigger falsely if NIP has either of > its two low bits set via sigreturn or ptrace, while SRR0 has its low two > bits masked in

[PATCH 1/3] powerpc/64s: Mask NIP before checking against SRR0

2021-12-21 Thread Michael Ellerman
When CONFIG_PPC_RFI_SRR_DEBUG=y we check that NIP and SRR0 match when returning from interrupts. This can trigger falsely if NIP has either of its two low bits set via sigreturn or ptrace, while SRR0 has its low two bits masked in hardware. As a quick fix make sure to mask the low bits before doin