From nobody Tue Feb 10 03:44:53 2026 Received: from mail-wr1-f74.google.com (mail-wr1-f74.google.com [209.85.221.74]) (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 4E3452253EC for ; Fri, 10 Jan 2025 18:41:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.74 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736534513; cv=none; b=BtaaF95vND7cy+zJic+KPSi5rtIqtOsm0RwvAxZJ7btRqP4kMs1BSp9YKx+/fxUdLj5n0nciaGmH4tV4SdJbhakzONu25YyksT2cCNSc51rlVaPXuIR2llbABl4GMG5h5Wu9gz+Y4aaljfBerJ982I251uKoQdIrUJOaEzzKJCo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736534513; c=relaxed/simple; bh=4d7pidGbvdIp8iHsT7YACeXpM+11EgA5LY+ovyRSffk=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=ICDWdlvuVFA1lLPsF3pGltTstupdPQnZE8LYkIIq3FIloudcMt9UKB/gfo1AoDPk3FIjHpYfhYFq+F1iZyrr47ZW/KhDEzCv47rXDDPsr+Fig2yIlP6inDujHczWRaxwxk08SI8p/8V3+7QB29yiXEuIMqRxJbZS2qJ5fSeJ4R8= 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=x/fetZE9; arc=none smtp.client-ip=209.85.221.74 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="x/fetZE9" Received: by mail-wr1-f74.google.com with SMTP id ffacd0b85a97d-386333ea577so964911f8f.1 for ; Fri, 10 Jan 2025 10:41:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1736534486; x=1737139286; 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=+fqV4f6s/Eo+EZ+PE2OCyE0kBm/vfnsLcFKRz+1otrE=; b=x/fetZE9fqENNHA/TK7J3oNSgvGr+mTjENc36PJ4rqxoixGMSS2It48gQWpx5s1gLQ Q1bsI0nE5oPMsCrnK07kvVUSVDiVdcnQz0NDggu7QBOA49tfKncNEEKcZ+tcwl35q1iB ZW7Tq5/dKeWJMGEMwbIsEwh8eqNEPfjCaU15NIF/lDZc/wXJB2vS5oM+kKLEbmWg4eTH FDOIZ8zuvDv/Sit/wd2xrxF+AyAShMGCcD3ko6RY2pPVMsItRF+lXGxNuvVyg5XVlQBO 8Nlrte9RJKZ5VdXMsskcV/p46JPYnucaAu8MnqMqBS0QbQzJ2h+yOejkpfafbu2lbMQe STZA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1736534486; x=1737139286; 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=+fqV4f6s/Eo+EZ+PE2OCyE0kBm/vfnsLcFKRz+1otrE=; b=UWqfV1JC+TYq3S+eBqWQy8kO5WcoKoFBoYo+okKhEdtVkhSinMebKL2fIcY001jAT9 fWEQso3haq/fXQA8x2QoPKf49BLBEGtRnInOg9PBaCsl1bo0hvjJ8xQ10MDPv1a3gvSP otJt8Fyg8WJowAp31v1dpk5fxmlOIe0HY5meSg9nhDXn8khCGw4z2iKSvhwLZccp15LG C0a5XLmdq4zMg+g13LuNQA3wOU0loSM2SBjNPiCaE6msg3HrZyyVOTQg3INtUz2CcZvZ qEGIP4S7NR578djO0BBbLoPBQEpT9H0vy+uww0HkPSju+1oDqZWtPKPvaPRJE1nviama ih0w== X-Forwarded-Encrypted: i=1; AJvYcCVviRtBUsvqY4HhMBGC4JLw2RlzvROdbl65ZgQKbZpVNRJ2NmgScgorJirqlHBvFxxQwHgFEZmgT4rGC4g=@vger.kernel.org X-Gm-Message-State: AOJu0YyQjWPS/3dFXiRZknvDNJrbYXeBAHF2ogqhO1+4Gh/CSHlc70r/ 3f/04X+xSCn0grLAA0dtZXyk5FTSe5xFxV7p0qH8WYraitlDZaK+iFqjb0s6nChwvAcrDmD8zij IMXhTPrhKug== X-Google-Smtp-Source: AGHT+IFgJUpClA++DtJe4xQ45Yc9kKsVSyJCXKqF0cxpPlCBfuMButRzIe/JLM7ynzshFcOsnG5hhjluySNsEA== X-Received: from wrbeh5.prod.google.com ([2002:a05:6000:4105:b0:382:4235:c487]) (user=jackmanb job=prod-delivery.src-stubby-dispatcher) by 2002:adf:8b5b:0:b0:38a:88bc:aea4 with SMTP id ffacd0b85a97d-38a88bcaebfmr7355114f8f.30.1736534486264; Fri, 10 Jan 2025 10:41:26 -0800 (PST) Date: Fri, 10 Jan 2025 18:40:44 +0000 In-Reply-To: <20250110-asi-rfc-v2-v2-0-8419288bc805@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250110-asi-rfc-v2-v2-0-8419288bc805@google.com> X-Mailer: b4 0.15-dev Message-ID: <20250110-asi-rfc-v2-v2-18-8419288bc805@google.com> Subject: [PATCH RFC v2 18/29] mm: asi: Map dynamic percpu memory as nonsensitive From: Brendan Jackman To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Andy Lutomirski , Peter Zijlstra , Richard Henderson , Matt Turner , Vineet Gupta , Russell King , Catalin Marinas , Will Deacon , Guo Ren , Brian Cain , Huacai Chen , WANG Xuerui , Geert Uytterhoeven , Michal Simek , Thomas Bogendoerfer , Dinh Nguyen , Jonas Bonn , Stefan Kristiansson , Stafford Horne , "James E.J. Bottomley" , Helge Deller , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Naveen N Rao , Madhavan Srinivasan , Paul Walmsley , Palmer Dabbelt , Albert Ou , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Yoshinori Sato , Rich Felker , John Paul Adrian Glaubitz , "David S. Miller" , Andreas Larsson , Richard Weinberger , Anton Ivanov , Johannes Berg , Chris Zankel , Max Filippov , Arnd Bergmann , Andrew Morton , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Uladzislau Rezki , Christoph Hellwig , Masami Hiramatsu , Mathieu Desnoyers , Mike Rapoport , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , Dennis Zhou , Tejun Heo , Christoph Lameter , Sean Christopherson , Paolo Bonzini , Ard Biesheuvel , Josh Poimboeuf , Pawan Gupta Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, loongarch@lists.linux.dev, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-openrisc@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, kvm@vger.kernel.org, linux-efi@vger.kernel.org, Brendan Jackman , Reiji Watanabe , Junaid Shahid Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable From: Reiji Watanabe Currently, all dynamic percpu memory is implicitly (and unintentionally) treated as sensitive memory. Unconditionally map pages for dynamically allocated percpu memory as global nonsensitive memory, other than pages that are allocated for pcpu_{first,reserved}_chunk during early boot via memblock allocator (these will be taken care by the following patch). We don't support sensitive percpu memory allocation yet. Co-developed-by: Junaid Shahid Signed-off-by: Junaid Shahid Signed-off-by: Reiji Watanabe Signed-off-by: Brendan Jackman WIP: Drop VM_SENSITIVE checks from percpu code --- mm/percpu-vm.c | 50 ++++++++++++++++++++++++++++++++++++++++++++------ mm/percpu.c | 4 ++-- 2 files changed, 46 insertions(+), 8 deletions(-) diff --git a/mm/percpu-vm.c b/mm/percpu-vm.c index cd69caf6aa8d8eded2395eb4bc4051b78ec6aa33..2935d7fbac41548819a94dcc605= 66bd18cde819a 100644 --- a/mm/percpu-vm.c +++ b/mm/percpu-vm.c @@ -132,11 +132,20 @@ static void pcpu_pre_unmap_flush(struct pcpu_chunk *c= hunk, pcpu_chunk_addr(chunk, pcpu_high_unit_cpu, page_end)); } =20 -static void __pcpu_unmap_pages(unsigned long addr, int nr_pages) +static void ___pcpu_unmap_pages(unsigned long addr, int nr_pages) { vunmap_range_noflush(addr, addr + (nr_pages << PAGE_SHIFT)); } =20 +static void __pcpu_unmap_pages(unsigned long addr, int nr_pages, + unsigned long vm_flags) +{ + unsigned long size =3D nr_pages << PAGE_SHIFT; + + asi_unmap(ASI_GLOBAL_NONSENSITIVE, (void *)addr, size); + ___pcpu_unmap_pages(addr, nr_pages); +} + /** * pcpu_unmap_pages - unmap pages out of a pcpu_chunk * @chunk: chunk of interest @@ -153,6 +162,8 @@ static void __pcpu_unmap_pages(unsigned long addr, int = nr_pages) static void pcpu_unmap_pages(struct pcpu_chunk *chunk, struct page **pages, int page_start, int page_end) { + struct vm_struct **vms =3D (struct vm_struct **)chunk->data; + unsigned long vm_flags =3D vms ? vms[0]->flags : VM_ALLOC; unsigned int cpu; int i; =20 @@ -165,7 +176,7 @@ static void pcpu_unmap_pages(struct pcpu_chunk *chunk, pages[pcpu_page_idx(cpu, i)] =3D page; } __pcpu_unmap_pages(pcpu_chunk_addr(chunk, cpu, page_start), - page_end - page_start); + page_end - page_start, vm_flags); } } =20 @@ -190,13 +201,38 @@ static void pcpu_post_unmap_tlb_flush(struct pcpu_chu= nk *chunk, pcpu_chunk_addr(chunk, pcpu_high_unit_cpu, page_end)); } =20 -static int __pcpu_map_pages(unsigned long addr, struct page **pages, - int nr_pages) +/* + * __pcpu_map_pages() should not be called during the percpu initializatio= n, + * as asi_map() depends on the page allocator (which isn't available yet + * during percpu initialization). Instead, ___pcpu_map_pages() can be used + * during the percpu initialization. But, any pages that are mapped with + * ___pcpu_map_pages() will be treated as sensitive memory, unless + * they are explicitly mapped with asi_map() later. + */ +static int ___pcpu_map_pages(unsigned long addr, struct page **pages, + int nr_pages) { return vmap_pages_range_noflush(addr, addr + (nr_pages << PAGE_SHIFT), PAGE_KERNEL, pages, PAGE_SHIFT); } =20 +static int __pcpu_map_pages(unsigned long addr, struct page **pages, + int nr_pages, unsigned long vm_flags) +{ + unsigned long size =3D nr_pages << PAGE_SHIFT; + int err; + + err =3D ___pcpu_map_pages(addr, pages, nr_pages); + if (err) + return err; + + /* + * If this fails, pcpu_map_pages()->__pcpu_unmap_pages() will call + * asi_unmap() and clean up any partial mappings. + */ + return asi_map(ASI_GLOBAL_NONSENSITIVE, (void *)addr, size); +} + /** * pcpu_map_pages - map pages into a pcpu_chunk * @chunk: chunk of interest @@ -214,13 +250,15 @@ static int __pcpu_map_pages(unsigned long addr, struc= t page **pages, static int pcpu_map_pages(struct pcpu_chunk *chunk, struct page **pages, int page_start, int page_end) { + struct vm_struct **vms =3D (struct vm_struct **)chunk->data; + unsigned long vm_flags =3D vms ? vms[0]->flags : VM_ALLOC; unsigned int cpu, tcpu; int i, err; =20 for_each_possible_cpu(cpu) { err =3D __pcpu_map_pages(pcpu_chunk_addr(chunk, cpu, page_start), &pages[pcpu_page_idx(cpu, page_start)], - page_end - page_start); + page_end - page_start, vm_flags); if (err < 0) goto err; =20 @@ -232,7 +270,7 @@ static int pcpu_map_pages(struct pcpu_chunk *chunk, err: for_each_possible_cpu(tcpu) { __pcpu_unmap_pages(pcpu_chunk_addr(chunk, tcpu, page_start), - page_end - page_start); + page_end - page_start, vm_flags); if (tcpu =3D=3D cpu) break; } diff --git a/mm/percpu.c b/mm/percpu.c index da21680ff294cb53dfb42bf0d3b3bbd2654d2cfa..c2d913c579bf07892957ac7f601= a6a71defadc4b 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -3273,8 +3273,8 @@ int __init pcpu_page_first_chunk(size_t reserved_size= , pcpu_fc_cpu_to_node_fn_t pcpu_populate_pte(unit_addr + (i << PAGE_SHIFT)); =20 /* pte already populated, the following shouldn't fail */ - rc =3D __pcpu_map_pages(unit_addr, &pages[unit * unit_pages], - unit_pages); + rc =3D ___pcpu_map_pages(unit_addr, &pages[unit * unit_pages], + unit_pages); if (rc < 0) panic("failed to map percpu area, err=3D%d\n", rc); =20 --=20 2.47.1.613.gc27f4b7a9f-goog