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charset=us-ascii Content-Disposition: inline In-Reply-To: <20251114182956.GD2566209@ax162> X-Rspamd-Queue-Id: 0D67A40017 X-Rspamd-Server: rspam07 X-Stat-Signature: y5mxb4qqahfsjmioaek31dupiabpou8q X-Rspam-User: X-HE-Tag: 1763146493-331413 X-HE-Meta: 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 P0apBphO 2R5bN2oysggN6Z4XlaRgY52DoR06+50tHTdB/5TlACrdtM9DOAhyRYjRHdWCHw14Us+mC07ZG5Sr4WLyhn1w5lSTDt7rvF4WkOTesHr8+svn4JKdKCyEXOUMRu7XzVci2Kc+XUi/nNLunsB0dajkaijmzRruRZk/LoE4rPsrCBkYYd0xLJP92MqN2HbkLvr7ukMGcyHhQKTsqAY4thDHc+hdpsBdkvdILOsIM4sjbmUlserhh04T+DuW4kbnUvLey/HiM 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 Fri, Nov 14, 2025 at 11:29:56AM -0700, Nathan Chancellor wrote: > > >> mm/util.c:1263:16: warning: implicit conversion from 'unsigned long long' to 'unsigned long' changes value from 17179869184 to 0 [-Wconstant-conversion] > > 1263 | if (ps->idx < MAX_FOLIO_NR_PAGES) { > > | ^~~~~~~~~~~~~~~~~~ > > include/linux/mm.h:2104:36: note: expanded from macro 'MAX_FOLIO_NR_PAGES' > > 2104 | #define MAX_FOLIO_NR_PAGES (1UL << MAX_FOLIO_ORDER) > > | ^~~~~~~~~~~~~~~ > > include/linux/mm.h:2095:36: note: expanded from macro 'MAX_FOLIO_ORDER' > > 2095 | #define MAX_FOLIO_ORDER get_order(SZ_16G) > > | ~~~~~~~~~ ^~~~~~ > > include/linux/sizes.h:56:19: note: expanded from macro 'SZ_16G' > > 56 | #define SZ_16G _AC(0x400000000, ULL) > > | ^~~~~~~~~~~~~~~~~~~~~ Clearly this is a 32-bit build, since otherwise a conversion from "unsigned long long" to "unsigned long" is a NOP. But 32-bit cannot support 16GB folios! I say this is a bug in powerpc32's config. #if !defined(CONFIG_ARCH_HAS_GIGANTIC_PAGE) #define MAX_FOLIO_ORDER MAX_PAGE_ORDER ... #else #define MAX_FOLIO_ORDER PUD_ORDER (PUD_ORDER is 16GB, so I think this will be what's being picked up) but the only place the mentions ARCH_HAS_GIGANTIC_PAGE is pretty clearly dependent on 64bit ... config PPC_RADIX_MMU bool "Radix MMU Support" depends on PPC_BOOK3S_64 select ARCH_HAS_GIGANTIC_PAGE so I'm a bit stuck about how this comes to be. Adding the PPC people for thoughts.