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Soft lockup was observed >>> when doing this for large HugeTLB memory area in our customer's workload >>> (~300GB memory): >> AFAICT this is a bug fix. The hugetlb path should be doing a >> cond_resched() like the base page code does. >> >> It is not MTE specific. If other processing takes a long time in the loop >> (setting up terabyte size mappings for hugetlb for example) then the >> softlockup could also be triggered on non MTE workloads. > Yeah, with MTE set_huge_pte_at() isn't just setting a pte but also > clearing the tags. So it can take considerable time. > > The fix is indeed not related to MTE, so I don't think the Fixes tag > should mention MTE (but I'm fine with a cc stable). Let's say we change > a hugetlb from RW to RX and have to do cache maintenance, we'd trigger a > similar soft lockup, depending on how fast the system is. > > Reviewed-by: Catalin Marinas Thank you. Yes, I agree this should be not MTE specific although it was triggered by MTE in certain workload. I will remove the fix tag and make the commit message more generic. Yang