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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 9D970C0005 X-Stat-Signature: dw6to7apsf3wzu5k6w5czp59c7smo8mr X-Rspam-User: X-Rspamd-Server: rspam05 X-HE-Tag: 1773026815-553222 X-HE-Meta: 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 q1nxkGbg 1jCam5Vd0miXpyNoedkbNZNqPScvcAylVC4P469n8D5x777Y5+VVpD6qDSHtt8WnsB0z3noC5mjoYL1pJAa+uBF/p1fH2xVV2mv/jiMFnhaoxrIaXRlmYjTtCjQ6o4DOT+fzMFkz6dlFxuX/0YNi78JUgESskPELAxzWVfEXDWlOzw9EgWtFldQ8QRzKJQK+4Nw8SlOavYTO9aneOgXcIc5Tpc+OPrxgay/O6OR3JzeB4VPki+OdRsVS0weoFLS6eFHPUknNMiFIP59FFYkTtu4yn2Fc78s8YDHez9SDnFyPOfRG3TKsfJsaBxNL9IXCMhqtrthCAhfJMA6pWhYN1hI5SyignrWlnCuhikBQ3OPQKxRHT5qY1UAs1YNNM88yvEm6E0fJn9bU5TDvXJgh8ucv4osFqjYpswwATBV0EM1fbtdSXjSSaq0sKW0w5ZfGqWm6jhYUqENnjKzQbEvA++RpnukSzoYZSdI3q Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 27/02/26 11:57 AM, Anshuman Khandual wrote: > Replace raw READ_ONCE() dereferences of pgtable entries with corresponding > standard page table accessors pxdp_get() in perf_get_pgtable_size(). These > accessors default to READ_ONCE() on platforms that don't override them. So > there is no functional change on such platforms. > > However arm64 platform is being extended to support 128 bit page tables via > a new architecture feature i.e FEAT_D128 in which case READ_ONCE() will not > provide required single copy atomic access for 128 bit page table entries. > Although pxdp_get() accessors can later be overridden on arm64 platform to > extend required single copy atomicity support on 128 bit entries. > > Cc: Andrew Morton > Cc: David Hildenbrand > Cc: Peter Zijlstra > Cc: Ingo Molnar > Cc: Arnaldo Carvalho de Melo > Cc: Namhyung Kim > Cc: linux-perf-users@vger.kernel.org > Cc: linux-mm@kvack.org > Cc: linux-kernel@vger.kernel.org > Acked-by: Peter Zijlstra (Intel) > Signed-off-by: Anshuman Khandual > --- > This patch applies both on v7.0-rc1 and mm-unstable. > > Part of the D128 series but independent. Hence could be considered on its own. > > https://lore.kernel.org/all/20260224051153.3150613-5-anshuman.khandual@arm.com/ > > Collected Peter's tag from an off list conversation. > > kernel/events/core.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/kernel/events/core.c b/kernel/events/core.c > index ac70d68217b6..4ee151cd2c6d 100644 > --- a/kernel/events/core.c > +++ b/kernel/events/core.c > @@ -8422,7 +8422,7 @@ static u64 perf_get_pgtable_size(struct mm_struct *mm, unsigned long addr) > pte_t *ptep, pte; > > pgdp = pgd_offset(mm, addr); > - pgd = READ_ONCE(*pgdp); > + pgd = pgdp_get(pgdp); > if (pgd_none(pgd)) > return 0; > > @@ -8430,7 +8430,7 @@ static u64 perf_get_pgtable_size(struct mm_struct *mm, unsigned long addr) > return pgd_leaf_size(pgd); > > p4dp = p4d_offset_lockless(pgdp, pgd, addr); > - p4d = READ_ONCE(*p4dp); > + p4d = p4dp_get(p4dp); > if (!p4d_present(p4d)) > return 0; > > @@ -8438,7 +8438,7 @@ static u64 perf_get_pgtable_size(struct mm_struct *mm, unsigned long addr) > return p4d_leaf_size(p4d); > > pudp = pud_offset_lockless(p4dp, p4d, addr); > - pud = READ_ONCE(*pudp); > + pud = pudp_get(pudp); > if (!pud_present(pud)) > return 0; > Don't see this patch in next-20260306. Is not this being picked for testing ?