From nobody Mon Apr 6 11:51:27 2026 Received: from mail-wm1-f73.google.com (mail-wm1-f73.google.com [209.85.128.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0E7D73E8C78 for ; Thu, 19 Mar 2026 16:08:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773936509; cv=none; b=FjQacA7lXEp5gjvGEJzNa/NzlzQbNRI+4zQVi4vrUktymzIeO2FXWoXl2n2EUnLt7kpPJlcjJLOl0TT7lbsJZgVrIVRADFeuqHCOBde/8iYqsS5i66LbxnPxEcJDkTgsFFrM5h/gXDH2xahckaJYtaWghbRz2tl5phyPm6EpTvw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773936509; c=relaxed/simple; bh=XMTHvLWdfwNKpLz73ivbyRPP8+gRpnHYOPqNhF56S+4=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=P2FPcsHlhbJWeQGDf8ylYBlDg5IIR+whwo3vLIFSzSjObQ2QxJiS1F3hm9KV15LxwdX9XXVjCnwES4uTs16HDIfSmgwZ2gqNZyiw8f+zPpJwSMd/f79qNK01OxU7R+U/iF6xNve5pM6z/51I+yGUULqecfzOjfJY/3PARzkIZqY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jackmanb.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=VyP4+KDc; arc=none smtp.client-ip=209.85.128.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--jackmanb.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="VyP4+KDc" Received: by mail-wm1-f73.google.com with SMTP id 5b1f17b1804b1-486fc42c83aso5869335e9.0 for ; Thu, 19 Mar 2026 09:08:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1773936506; x=1774541306; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=rjopGIRqFFR8FL/MLwWIQbXbXtXyPbnj+84kMxSBPQ8=; b=VyP4+KDchURjC2GHIB6ZK84H5zBm9dWOpV4bnrOZ0olS2Oay+b606ytXPdLZUhw32b ieUdgF72RypA4nP8p0PSl7vVSFgWVEJ4uefjeaShS2gXUSFJbtEV/EnIHeqN1hxf2zNl e58tXOvCSZulh3HzGufSwWdkZQYOhANghIG72RppLgfHtTHIj9AC5a1olzyrq6gNEmc1 0dpZ6EzfKs/eg5guQk/GCAcUHZjACurkwe6Mt2GoGnzsJtr9pOdk5l2Z28wTtYxuQADP 2ebUqPRYk2n8YGisp9cHK3WzTN4dX8Qx9+aK3sKQLsmN2suDXrLvqG2zHWdjhci8bfGX vH0Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1773936506; x=1774541306; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=rjopGIRqFFR8FL/MLwWIQbXbXtXyPbnj+84kMxSBPQ8=; b=RsBCELvGZ8BA9g6ZIJG4ZJwh/fjNx1R4OBFOloXwN3bE5fOCZrd6pv1jlx5avfCfvz mLR+50+rXsL4swXouhADE3ot4rjAg5RrdNCywZtZb4e5wXAv7+bQHDgyp6X3fyDazVFG MNKYEoey9LtMDsiHxkzhG+C8Lm6CNEhkNKD25WKekJiLPRjfO8NZujxPCbK9V682udFY AoN4bIFvmN7qTYsperBM1wXmV3copcuNcX+2hkJdADnfYyf4PnJ+1wd8tUJdsiiKLA+c PBGWtp5/paUoqPfaDGnlEcOYTrX1acMOdgI0SVErs7/Ot+z2zQgxiC/O/sYRBbvEv5Ow +qKA== X-Gm-Message-State: AOJu0YzUDqZDsLC77LMKii4HdCbhEdbx6izzi1/w9M2kQIHmJ/LNtOM+ XgL5KlrPg2KmD/p0T+XNvM0qFWE+xtObsC2K5rVzcMoBKDarnbGevMJBqZwgYSG34eWl1Abi9VN RTjgTPikI06TXZg== X-Received: from wmjq10.prod.google.com ([2002:a7b:ce8a:0:b0:485:2cf0:2668]) (user=jackmanb job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:810c:b0:477:b642:9dc1 with SMTP id 5b1f17b1804b1-486f4475342mr130632885e9.20.1773936506286; Thu, 19 Mar 2026 09:08:26 -0700 (PDT) Date: Thu, 19 Mar 2026 16:03:28 +0000 In-Reply-To: <20260319-gfp64-v1-0-2c73b8d42b7f@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260319-gfp64-v1-0-2c73b8d42b7f@google.com> X-Mailer: b4 0.14.3 Message-ID: <20260319-gfp64-v1-5-2c73b8d42b7f@google.com> Subject: [PATCH 5/5] mm: Change gfp_t to unsigned long From: Brendan Jackman To: Andrew Morton , Michal Hocko , David Rientjes , Shakeel Butt , Vlastimil Babka , Suren Baghdasaryan , Brendan Jackman , Johannes Weiner , Zi Yan , Harry Yoo , Hao Li , Christoph Lameter , Roman Gushchin , Uladzislau Rezki Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable GFP flag bits are starting to get scarce. There are upcoming features that can tolerate being 64-bit only, which offers a simple way to escape GFP bit scarcity: just make gfp_t 64 bits on 64 bit systems. Update mm-internal printk formats to use %lx - external format strings have already been decoupled from the size of gfp_t. Also lib/test_lockup.c which uses the arg in a module_param_unsafe() invocation where gfp_t doesn't work. Some care needs to be taken here with code that converts between ALLOC_* flags and GFP flags since the former are still unsigned int. The current code is fine but just to be safe, add a BUILD_BUG_ON() for each GFP flag that gets converted this way. Signed-off-by: Brendan Jackman --- include/linux/types.h | 2 +- lib/test_lockup.c | 2 +- mm/oom_kill.c | 2 +- mm/page_alloc.c | 5 ++++- mm/page_owner.c | 4 ++-- mm/slab_common.c | 2 +- mm/slub.c | 2 +- mm/vmalloc.c | 2 +- 8 files changed, 12 insertions(+), 9 deletions(-) diff --git a/include/linux/types.h b/include/linux/types.h index 7e71d260763c7..a8490c1381f99 100644 --- a/include/linux/types.h +++ b/include/linux/types.h @@ -160,7 +160,7 @@ typedef u64 dma_addr_t; typedef u32 dma_addr_t; #endif =20 -typedef unsigned int __bitwise gfp_t; +typedef unsigned long __bitwise gfp_t; typedef unsigned int __bitwise slab_flags_t; typedef unsigned int __bitwise fmode_t; =20 diff --git a/lib/test_lockup.c b/lib/test_lockup.c index c3fd87d6c2dd0..7adc03ac0b39d 100644 --- a/lib/test_lockup.c +++ b/lib/test_lockup.c @@ -130,7 +130,7 @@ module_param(alloc_pages_order, uint, 0400); MODULE_PARM_DESC(alloc_pages_order, "page order to allocate"); =20 static gfp_t alloc_pages_gfp =3D GFP_KERNEL; -module_param_unsafe(alloc_pages_gfp, uint, 0400); +module_param_unsafe(alloc_pages_gfp, unsigned long, 0400); MODULE_PARM_DESC(alloc_pages_gfp, "allocate pages with this gfp_mask, defa= ult GFP_KERNEL"); =20 static bool alloc_pages_atomic; diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 5c6c95c169ee8..272ecce090f75 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -458,7 +458,7 @@ static void dump_oom_victim(struct oom_control *oc, str= uct task_struct *victim) =20 static void dump_header(struct oom_control *oc) { - pr_warn("%s invoked oom-killer: gfp_mask=3D%#x(%pGg), order=3D%d, oom_sco= re_adj=3D%d\n", + pr_warn("%s invoked oom-killer: gfp_mask=3D%#lx(%pGg), order=3D%d, oom_sc= ore_adj=3D%d\n", current->comm, oc->gfp_mask, &oc->gfp_mask, oc->order, current->signal->oom_score_adj); if (!IS_ENABLED(CONFIG_COMPACTION) && oc->order) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 2d4b6f1a554ed..f0b9e8a950ee7 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -4036,7 +4036,7 @@ void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask,= const char *fmt, ...) va_start(args, fmt); vaf.fmt =3D fmt; vaf.va =3D &args; - pr_warn("%s: %pV, mode:%#x(%pGg), nodemask=3D%*pbl", + pr_warn("%s: %pV, mode:%#lx(%pGg), nodemask=3D%*pbl", current->comm, &vaf, gfp_mask, &gfp_mask, nodemask_pr_args(nodemask)); va_end(args); @@ -4504,6 +4504,9 @@ gfp_to_alloc_flags(gfp_t gfp_mask, unsigned int order) */ BUILD_BUG_ON(__GFP_HIGH !=3D (__force gfp_t) ALLOC_MIN_RESERVE); BUILD_BUG_ON(__GFP_KSWAPD_RECLAIM !=3D (__force gfp_t) ALLOC_KSWAPD); + /* Alloc flags are unsigned int, gfp_t may be larger. */ + BUILD_BUG_ON(___GFP_HIGH_BIT >=3D BITS_PER_TYPE(typeof(alloc_flags))); + BUILD_BUG_ON(___GFP_KSWAPD_RECLAIM_BIT >=3D BITS_PER_TYPE(typeof(alloc_fl= ags))); =20 /* * The caller may dip into page reserves a bit more if the caller diff --git a/mm/page_owner.c b/mm/page_owner.c index 8178e0be557f8..70afbdb945b1e 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -558,7 +558,7 @@ print_page_owner(char __user *buf, size_t count, unsign= ed long pfn, return -ENOMEM; =20 ret =3D scnprintf(kbuf, count, - "Page allocated via order %u, mask %#x(%pGg), pid %d, tgid %d (%s), ts = %llu ns\n", + "Page allocated via order %u, mask %#lx(%pGg), pid %d, tgid %d (%s), ts= %llu ns\n", page_owner->order, page_owner->gfp_mask, &page_owner->gfp_mask, page_owner->pid, page_owner->tgid, page_owner->comm, @@ -630,7 +630,7 @@ void __dump_page_owner(const struct page *page) else pr_alert("page_owner tracks the page as freed\n"); =20 - pr_alert("page last allocated via order %u, migratetype %s, gfp_mask %#x(= %pGg), pid %d, tgid %d (%s), ts %llu, free_ts %llu\n", + pr_alert("page last allocated via order %u, migratetype %s, gfp_mask %#lx= (%pGg), pid %d, tgid %d (%s), ts %llu, free_ts %llu\n", page_owner->order, migratetype_names[mt], gfp_mask, &gfp_mask, page_owner->pid, page_owner->tgid, page_owner->comm, page_owner->ts_nsec, page_owner->free_ts_nsec); diff --git a/mm/slab_common.c b/mm/slab_common.c index d5a70a831a2a5..548e0d0f9aab3 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -1028,7 +1028,7 @@ gfp_t kmalloc_fix_flags(gfp_t flags) gfp_t invalid_mask =3D flags & GFP_SLAB_BUG_MASK; =20 flags &=3D ~GFP_SLAB_BUG_MASK; - pr_warn("Unexpected gfp: %#x (%pGg). Fixing up to gfp: %#x (%pGg). Fix yo= ur code!\n", + pr_warn("Unexpected gfp: %#lx (%pGg). Fixing up to gfp: %#lx (%pGg). Fix = your code!\n", invalid_mask, &invalid_mask, flags, &flags); dump_stack(); =20 diff --git a/mm/slub.c b/mm/slub.c index 2b2d33cc735cb..083f4e9de3ecb 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -4235,7 +4235,7 @@ slab_out_of_memory(struct kmem_cache *s, gfp_t gfpfla= gs, int nid) if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slub_oom_rs)) return; =20 - pr_warn("SLUB: Unable to allocate memory on CPU %u (of node %d) on node %= d, gfp=3D%#x(%pGg)\n", + pr_warn("SLUB: Unable to allocate memory on CPU %u (of node %d) on node %= d, gfp=3D%#lx(%pGg)\n", cpu, cpu_to_node(cpu), nid, gfpflags, &gfpflags); pr_warn(" cache: %s, object size: %u, buffer size: %u, default order: %u= , min order: %u\n", s->name, s->object_size, s->size, oo_order(s->oo), diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 61caa55a44027..e353e281fa95d 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -3949,7 +3949,7 @@ static gfp_t vmalloc_fix_flags(gfp_t flags) gfp_t invalid_mask =3D flags & ~GFP_VMALLOC_SUPPORTED; =20 flags &=3D GFP_VMALLOC_SUPPORTED; - WARN_ONCE(1, "Unexpected gfp: %#x (%pGg). Fixing up to gfp: %#x (%pGg). F= ix your code!\n", + WARN_ONCE(1, "Unexpected gfp: %#lx (%pGg). Fixing up to gfp: %#lx (%pGg).= Fix your code!\n", invalid_mask, &invalid_mask, flags, &flags); return flags; } --=20 2.51.2