From: Nicholas Piggin Date: Tue, 25 Feb 2020 17:35:31 +0000 (+1000) Subject: powerpc/64s/exception: Soft NMI interrupt should not use ret_from_except X-Git-Tag: v5.10.7~2835^2~49 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=71c3b05a8083d8774ca66c89672d29d7bf33813e;p=platform%2Fkernel%2Flinux-rpi.git powerpc/64s/exception: Soft NMI interrupt should not use ret_from_except The soft NMI handler does not reconcile interrupt state, so it should not return via the normal ret_from_except path. Return like other NMIs, using the EXCEPTION_RESTORE_REGS macro. This becomes important when the scv interrupt is implemented, which must handle soft-masked interrupts that have r13 set to something other than the PACA -- returning to kernel in this case must restore r13. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200225173541.1549955-23-npiggin@gmail.com --- diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 3ddabac..d75df22 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -2731,6 +2731,7 @@ EXC_VIRT_NONE(0x5800, 0x100) INT_DEFINE_BEGIN(soft_nmi) IVEC=0x900 ISTACK=0 + IRECONCILE=0 /* Soft-NMI may fire under local_irq_disable */ INT_DEFINE_END(soft_nmi) /* @@ -2749,9 +2750,36 @@ EXC_COMMON_BEGIN(soft_nmi_common) subi r1,r1,INT_FRAME_SIZE __GEN_COMMON_BODY soft_nmi bl save_nvgprs + + /* + * Set IRQS_ALL_DISABLED and save PACAIRQHAPPENED (see + * system_reset_common) + */ + li r10,IRQS_ALL_DISABLED + stb r10,PACAIRQSOFTMASK(r13) + lbz r10,PACAIRQHAPPENED(r13) + std r10,_DAR(r1) + ori r10,r10,PACA_IRQ_HARD_DIS + stb r10,PACAIRQHAPPENED(r13) + addi r3,r1,STACK_FRAME_OVERHEAD bl soft_nmi_interrupt - b ret_from_except + + /* Clear MSR_RI before setting SRR0 and SRR1. */ + li r9,0 + mtmsrd r9,1 + + /* + * Restore soft mask settings. + */ + ld r10,_DAR(r1) + stb r10,PACAIRQHAPPENED(r13) + ld r10,SOFTE(r1) + stb r10,PACAIRQSOFTMASK(r13) + + kuap_restore_amr r10 + EXCEPTION_RESTORE_REGS hsrr=0 + RFI_TO_KERNEL #endif /* CONFIG_PPC_WATCHDOG */