From 551d44200152cb26f75d2ef990aeb6185b7e37fd Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 23 Feb 2026 09:33:08 -0800 Subject: default_gfp(): avoid using the "newfangled" __VA_OPT__ trick The default_gfp() helper that I added is not wrong, but it turns out that it causes unnecessary headaches for 'sparse' which doesn't support the use of __VA_OPT__ (introduced in C++20 and C23, and supported by gcc and clang for a long time). We do already use __VA_OPT__ in some other cases in the kernel (drm/xe and btrfs), but it has been fairly limited. Now it triggers for pretty much everything, and sparse ends up not working at all. We can use the traditional gcc ',##__VA_ARGS__' syntax instead: it may not be the "C standard" way and is slightly less natural in this context, but it is the traditional model for this and avoids the sparse problem. Reported-and-tested-by: Ricardo Ribalda Reported-and-tested-by: Richard Fitzgerald Reported-by: Ben Dooks Fixes: e19e1b480ac7 ("add default_gfp() helper macro and use it in the new *alloc_obj() helpers") Signed-off-by: Linus Torvalds --- include/linux/gfp.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/gfp.h') diff --git a/include/linux/gfp.h b/include/linux/gfp.h index 2b30a0529d48..90536b2bc42e 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -14,8 +14,8 @@ struct vm_area_struct; struct mempolicy; /* Helper macro to avoid gfp flags if they are the default one */ -#define __default_gfp(a,...) a -#define default_gfp(...) __default_gfp(__VA_ARGS__ __VA_OPT__(,) GFP_KERNEL) +#define __default_gfp(a,b,...) b +#define default_gfp(...) __default_gfp(,##__VA_ARGS__,GFP_KERNEL) /* Convert GFP flags to their corresponding migrate type */ #define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE) -- cgit v1.2.3 From eb9549346f7578eda3755683ac2cfb4d94c0675f Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 16 Feb 2026 13:17:44 +0100 Subject: mm: change vma_alloc_folio_noprof() macro to inline function In a few rare configurations with extra warnings eanbled, the new drm_pagemap_migrate_populate_ram_pfn() calls vma_alloc_folio_noprof() but that does not use all the arguments, leading to a harmless warning: drivers/gpu/drm/drm_pagemap.c: In function 'drm_pagemap_migrate_populate_ram_pfn': drivers/gpu/drm/drm_pagemap.c:701:63: error: parameter 'addr' set but not used [-Werror=unused-but-set-parameter=] 701 | unsigned long addr) | ~~~~~~~~~~~~~~^~~~ Replace the macro with an inline function so the compiler can see how the argument would be used, but is still able to optimize out the assignments. Link: https://lkml.kernel.org/r/20260216121751.2378374-1-arnd@kernel.org Signed-off-by: Arnd Bergmann Reviewed-by: Lorenzo Stoakes Acked-by: Zi Yan Reviewed-by: Suren Baghdasaryan Cc: Alexei Starovoitov Cc: Brendan Jackman Cc: David Hildenbrand Cc: Johannes Weiner Cc: Joshua Hahn Cc: Kefeng Wang Cc: Liam Howlett Cc: Michal Hocko Cc: Mike Rapoport Cc: Shakeel Butt Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- include/linux/gfp.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'include/linux/gfp.h') diff --git a/include/linux/gfp.h b/include/linux/gfp.h index 2b30a0529d48..f82d74a77cad 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -339,8 +339,11 @@ static inline struct folio *folio_alloc_mpol_noprof(gfp_t gfp, unsigned int orde { return folio_alloc_noprof(gfp, order); } -#define vma_alloc_folio_noprof(gfp, order, vma, addr) \ - folio_alloc_noprof(gfp, order) +static inline struct folio *vma_alloc_folio_noprof(gfp_t gfp, int order, + struct vm_area_struct *vma, unsigned long addr) +{ + return folio_alloc_noprof(gfp, order); +} #endif #define alloc_pages(...) alloc_hooks(alloc_pages_noprof(__VA_ARGS__)) -- cgit v1.2.3