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Message-ID: <20260602100358.GQ3102624@noisy.programming.kicks-ass.net> References: <7904105b-9dfa-4efd-a5ef-bc0276ed255d@linux.ibm.com> <2f8c3d75-de2c-48bf-bd05-46b816d55c69@linux.ibm.com> <20260601095601.GN3102624@noisy.programming.kicks-ass.net> <37e69c39-564b-4ca9-bb27-1b99faab540c@linux.ibm.com> <20260602081845.GX3126523@noisy.programming.kicks-ass.net> X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Tue, Jun 02, 2026 at 03:26:11PM +0530, Shrikanth Hegde wrote: > > I would suggest trying something a little more focussed like so: > > > > diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c > > index 806c74e0d5ab..b002c179415c 100644 > > --- a/arch/powerpc/mm/fault.c > > +++ b/arch/powerpc/mm/fault.c > > @@ -589,6 +589,7 @@ static __always_inline void __do_page_fault(struct pt_regs *regs) > > err = ___do_page_fault(regs, regs->dar, regs->dsisr); > > if (unlikely(err)) > > bad_page_fault(regs, err); > > + local_irq_disable(); > > } > > DEFINE_INTERRUPT_HANDLER(do_page_fault) > > > > Since only ___do_page_fault() will enable interrupts, you only need to > > disable them again on its return path. > > > > Seems there are more... > > do_program_check (called by program_check_exception, emulation_assist_interrupt) > alignment_exception > SPEFloatingPointException > facility_unavailable_exception > > > Many looks like it can recover only if hit in userspace. > Hence i though it would make sense to put it under arch_interrupt_exit_prepare > which is called just before irqentry_exit. Ah, fair enough.