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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Stat-Signature: a8h87xeho4cn79cwj3tr8cefs9n18jz6 X-Rspam-User: X-Rspamd-Queue-Id: AFD6640006 X-Rspamd-Server: rspam08 X-HE-Tag: 1742530919-489427 X-HE-Meta: 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 8jsYQipa M3Tn/sqm/NE8Vvsm/0PMRgQAjSFZqjBBbbL96McaRNgklNEiS6/+RfQgpNtDU55SK2DnnoD5OlCieeokqDxbmh6BgIt4bHHgfiXTpuHWVEA2VMHKkry5ejmwFocOOaQCcKAY9rhgRFUNNSTf3y9CVA7gqQ3rhcsU90uhFXEXLlQ5ou94uQFzRHjuqJZNHZ277U23Y63UdkHaJQTtqZWGGZyURPHAIgSoKnELJuQVMOISXOfCONxgr6zEV/rw+NYvUyo4NZcFGZVQhrQTJq4cSpasOVvoGdfvmJqi8LI2BUjegV5dFcW2pWESvfA== 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 3/21/25 00:04, Peter Xu wrote: > Keith Busch observed some incorrect macros defined in arm64 code [1]. > > It turns out the two lines should never be needed and won't be exposed to > anyone, because aarch64 doesn't select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD, > hence ARCH_SUPPORTS_PUD_PFNMAP is always N. The only archs that support > THP PUDs so far are x86 and powerpc. Correct. > > Instead of fixing the lines (with no way to test it..), remove the two > lines that are in reality dead code, to avoid confusing readers. Agreed. Because ARCH_SUPPORTS_PUD_PFNMAP is always N and hence these lines are never reachable. So removing these lines will be preferred than fixing. > > Fixes tag is attached to reflect where the wrong macros were introduced, > but explicitly not copying stable, because there's no real issue to be > fixed. So it's only about removing the dead code so far. Makes sense. > > [1] https://lore.kernel.org/all/Z9tDjOk-JdV_fCY4@kbusch-mbp.dhcp.thefacebook.com/#t > > Cc: Alex Williamson > Cc: Donald Dutile > Cc: Catalin Marinas > Cc: Will Deacon > Fixes: 3e509c9b03f9 ("mm/arm64: support large pfn mappings") The commit ID checks out. > Reported-by: Keith Busch > Signed-off-by: Peter Xu > --- > arch/arm64/include/asm/pgtable.h | 5 ----- > 1 file changed, 5 deletions(-) > > diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h > index 0b2a2ad1b9e8..15211f74b035 100644 > --- a/arch/arm64/include/asm/pgtable.h > +++ b/arch/arm64/include/asm/pgtable.h > @@ -620,11 +620,6 @@ static inline pmd_t pmd_mkspecial(pmd_t pmd) > #define pud_pfn(pud) ((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT) > #define pfn_pud(pfn,prot) __pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)) > > -#ifdef CONFIG_ARCH_SUPPORTS_PUD_PFNMAP > -#define pud_special(pte) pte_special(pud_pte(pud)) > -#define pud_mkspecial(pte) pte_pud(pte_mkspecial(pud_pte(pud))) > -#endif > - > #define pmd_pgprot pmd_pgprot > static inline pgprot_t pmd_pgprot(pmd_t pmd) > { LGTM Reviewed-by: Anshuman Khandual