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charset=utf-8 Content-Disposition: inline In-Reply-To: <20260122034017.505589-1-longman@redhat.com> X-Rspamd-Server: rspam11 X-Stat-Signature: km9wdxtjt83x1tf339ehidj5t3d1r19r X-Rspam-User: X-Rspamd-Queue-Id: 3B04C8000B X-HE-Tag: 1769068750-842756 X-HE-Meta: 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 Pz/JTvKa nEIs703S42CAcS8qlLJ98ErdIXcq3C+WUvSH8NnjYLFdA1hujItlfalBcSSuUbXuyZ1Wy4GleMNdNXycdyzjKoJOpdqj1GKxoyq/KbEBUP4kjQIdiE/P1CNOa+9RQLFa3NerM9i8ZQra+/Skr14Q3uxIclU9dlzps7jaHmQSYV0O6wl/PcHn4kVHlEXMGXQv6nnbORmY0XE8B+P3RZJsH02KR9cUmQCMTli57Nkz+a/5qY1Yq7fqecGtjtWoShQDLNhh7uF/E8UXBbjnGABdla6KXKKn5P5mfhr12YhqqP9eI+T2x+RnL3V1PZGw3l6GW+mmITbaby9wn0LgwibPoMuTqqw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2026-01-21 22:40:17 [-0500], Waiman Long wrote: > --- a/mm/mm_init.c > +++ b/mm/mm_init.c > @@ -2085,7 +2086,12 @@ deferred_init_memmap_chunk(unsigned long start_pfn, unsigned long end_pfn, > > spfn = chunk_end; > > - if (irqs_disabled()) > + /* > + * pgdat_resize_lock() only disables irqs in non-RT > + * kernels but implies rcu_read_lock() in a PREEMPT_RT > + * kernel. > + */ > + if (irqs_disabled() || rcu_preempt_depth()) > touch_nmi_watchdog(); > else > cond_resched(); What about (as suggested in the previous mail) diff --git a/mm/mm_init.c b/mm/mm_init.c index fc2a6f1e518f1..0b283fd48b282 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -2059,7 +2059,7 @@ static unsigned long __init deferred_init_pages(struct zone *zone, */ static unsigned long __init deferred_init_memmap_chunk(unsigned long start_pfn, unsigned long end_pfn, - struct zone *zone) + struct zone *zone, bool may_schedule) { int nid = zone_to_nid(zone); unsigned long nr_pages = 0; @@ -2085,10 +2085,10 @@ deferred_init_memmap_chunk(unsigned long start_pfn, unsigned long end_pfn, spfn = chunk_end; - if (irqs_disabled()) - touch_nmi_watchdog(); - else + if (may_schedule) cond_resched(); + else + touch_nmi_watchdog(); } } @@ -2101,7 +2101,7 @@ deferred_init_memmap_job(unsigned long start_pfn, unsigned long end_pfn, { struct zone *zone = arg; - deferred_init_memmap_chunk(start_pfn, end_pfn, zone); + deferred_init_memmap_chunk(start_pfn, end_pfn, zone, true); } static unsigned int __init @@ -2216,7 +2216,7 @@ bool __init deferred_grow_zone(struct zone *zone, unsigned int order) for (spfn = first_deferred_pfn, epfn = SECTION_ALIGN_UP(spfn + 1); nr_pages < nr_pages_needed && spfn < zone_end_pfn(zone); spfn = epfn, epfn += PAGES_PER_SECTION) { - nr_pages += deferred_init_memmap_chunk(spfn, epfn, zone); + nr_pages += deferred_init_memmap_chunk(spfn, epfn, zone, false); } /* Sebastian