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charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: DC6D940005 X-Stat-Signature: ngh13jxzn89p7da6e8mr5mzkqfh3yiju X-HE-Tag: 1759732105-898929 X-HE-Meta: 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 AYGOmi1A bBM++sm1U4ceKUT2PpWehcw7xZ58kM8nxBvfXo7+z1j1o52pe2Xjiab80RRaz1LQXpM2eIG2Sg+u3cpwHe6q4BOX+Z8A+BanY87MLaGxUWUSFkLanRnYNwiETa7DZ8umes3hlqSI3tnPBmWoRZrWtBi1OkqkgJvCmkX5WZ1KIkAZyMkiUbog9HN5CsZVjq7ls6Gg2vD/cs5OT4P+Ix4LdzWg7YbZP6fVKBscepmS4vdvZwuV6VK4RvJJQoG5h0F3QmaNk6emmL+PK1HLDr4iDqQ74sDpqVwjrfIOXgWiTls2u0OAyhDBcmgsn3qP+imATDPuT0dviy/EFguq4poJEjBt0Cm1t5cF2f9EnICnHYBf0a+f+9hL6k9f+mjYouRS/ENVu/tERD0h6Kq8= 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 06/10/25 11:37 AM, Dev Jain wrote: > > On 06/10/25 11:22 am, Anshuman Khandual wrote: >> Replace READ_ONCE() with a standard page table accessor i.e pudp_get() that >> anyways defaults into READ_ONCE() in cases where platform does not override >> >> Cc: Andrew Morton >> Cc: David Hildenbrand >> Cc: linux-mm@kvack.org >> Cc: linux-kernel@vger.kernel.org >> Signed-off-by: Anshuman Khandual >> --- >>   mm/mapping_dirty_helpers.c | 2 +- >>   1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/mm/mapping_dirty_helpers.c b/mm/mapping_dirty_helpers.c >> index c193de6cb23a..737c407f4081 100644 >> --- a/mm/mapping_dirty_helpers.c >> +++ b/mm/mapping_dirty_helpers.c >> @@ -149,7 +149,7 @@ static int wp_clean_pud_entry(pud_t *pud, unsigned long addr, unsigned long end, >>                     struct mm_walk *walk) >>   { >>   #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD >> -    pud_t pudval = READ_ONCE(*pud); >> +    pud_t pudval = pudp_get(pud); >>         /* Do not split a huge pud */ >>       if (pud_trans_huge(pudval)) { > > Talking about mm, why not also make changes for these READ_ONCE accesses > in gup, hmm, memory, mprotect, sparse-vmemmap? > Right, could replace all mm/ READ_ONCE() for pxdp pointers with the pgtable helpers but that will create too much code churn in a single patch. Thought of doing these replacements per file will be much more contained which is easy both for review and testing.