From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) (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 DD1FB3B993B for ; Mon, 20 Jul 2026 17:15:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.70 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784567731; cv=none; b=lDCYZrGqz9QnC2gDrZLVQpxwW24ESayHutKR9b2wBRX0GDP2dSRR41aMxHEB7XsF5pduChCmb7xVlj1eqkhm5T699JcpUVhyy5p4iRPLu3yi8+6syn9zB+8z3BiiIpjUz8DZDB95OErgj60kktdHMOPvvkKGcdrUwgyh52aYqAA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784567731; c=relaxed/simple; bh=p1muMmj/qKCzGdg0wYvbAabYSjWJ8IMl7J2O+YS+1TQ=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=Gzjz8kqHasoC5ry4dK9LQwKgqplHBaKX4hrdhHNPxEavJLFkh4EGmtf3yH40DDFI8OpEkFddI9WqeIrpj0xmzBYqNl1eoZ29Kt3uXB3i5gaIaIGAoL0LgUWfWiHdSSLwkd27CL7x8ze1JYsupyXekkmGvmbNyXir2VT9ANtxqow= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--vdonnefort.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=W0sv6wKW; arc=none smtp.client-ip=209.85.208.70 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--vdonnefort.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="W0sv6wKW" Received: by mail-ed1-f70.google.com with SMTP id 4fb4d7f45d1cf-69c033344cdso5170799a12.2 for ; Mon, 20 Jul 2026 10:15:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1784567724; x=1785172524; darn=lists.linux.dev; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:from:to:cc:subject:date:message-id:reply-to :content-type; bh=coQ8Sg2Gg4wBmuVDYw7iK7AOHNH8rxxYYghY3YcY7oQ=; b=W0sv6wKWoc3pklUn1diTd4eC4biqyF0+cxnvpy5ZjWz0q21Q7KY+XH1yGXmCP0OMg3 apX5Yqvz3EamTn20aybXEa1t0lb+lBMtV2cV9DG8ZTjP2fWfTNxxvskqs3WDHb0tlUBx FnOJ4S9/QpLgjRZytwhK44zfH707EkjmQTcM/3wsiHmZJD+AVTjpQDtODGGC/2Vg9MCm 5KQzWo43wfavTXnE/Yg2szmzGzXhafXCtSIrLbN6Ytjx4uvHRRzl/zaKKZESOZJsicdk vxTx7iY6S55Y9QmF0UH1RGpDjJ/F8Z0perLF5bTXExLf/HWlkfd2dPmCeG64OTMSnyeQ waRQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784567724; x=1785172524; h=content-type: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:content-type; bh=coQ8Sg2Gg4wBmuVDYw7iK7AOHNH8rxxYYghY3YcY7oQ=; b=LkVnRBaWTqpl05Zr70z2kNKTga75IDpGhNKQ501tRE/pT6bAk5JbxxDlv4g1BeIzBO nvwmb7i2wfodUYUXXoDIsYkntUSz7azFbKfkKjDwlshH1upd4wefTaGnyIEMLhjm7gCq 7fUqBosNj09ZmYfUIP0DkjjbBuTewv+dfpgkzAO9EKr/pcsuIXIDLNTZZySAmc5swran LePHSEG31+/DyUUexyTpR6e8hQAG/F6VX6zHyyypmzSYoSYdBeU08+MmZoO4ucpWE3Cd XjyLir0yfEcFSPBEfvUf+Id5i6HQXU164+VqkqivvaaHB30HHtztPPZi3xO8RiFwRrP+ C/pA== X-Forwarded-Encrypted: i=1; AHgh+RpwIa2aWEiW2AZ5LSfBUsa1YESYJJ1MyIf596gb8BSpuPDQvWnVJZNMi6ChJ9df0ZDri/Vmhxw=@lists.linux.dev X-Gm-Message-State: AOJu0YxOZrTLoihjbAK2PBjnhF4tvvfqv6qvBvfqXkGI45khTJQ22Ak8 YGvGPZL6ZTmu6CyogsqvmBhlXj6qAAhMgkYLYYbsQcWkkH//YJ2YahmgybmkrSrbmCqmbEO3MiW 7qYdBIzSiGr2lovyw8ai7Uw== X-Received: from edev9-n1.prod.google.com ([2002:a05:6402:a2c9:10b0:698:ad4b:abf5]) (user=vdonnefort job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6402:4409:b0:69a:9355:d1c6 with SMTP id 4fb4d7f45d1cf-69e653279b9mr5624442a12.42.1784567723872; Mon, 20 Jul 2026 10:15:23 -0700 (PDT) Date: Mon, 20 Jul 2026 18:15:01 +0100 In-Reply-To: <20260720171513.1415357-1-vdonnefort@google.com> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260720171513.1415357-1-vdonnefort@google.com> X-Mailer: git-send-email 2.55.0.229.g6434b31f56-goog Message-ID: <20260720171513.1415357-6-vdonnefort@google.com> Subject: [PATCH v3 05/17] KVM: arm64: Allow kvm_hyp_memcache usage outside of stage-2 From: Vincent Donnefort To: maz@kernel.org, oupton@kernel.org, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org Cc: joey.gouly@arm.com, seiden@linux.ibm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, kernel-team@android.com, tabba@google.com, qperret@google.com, Vincent Donnefort , Fuad Tabba Content-Type: text/plain; charset="UTF-8" Although currently limited to guest stage-2 page-table allocations, struct kvm_hyp_memcache is a useful primitive for passing a list of discontiguous pages between host and hypervisor. Introduce init_hyp_memcache() to initialise a generic hyp memcache, and init_hyp_stage2_memcache() for stage-2 specific memcaches. The generic initialiser will be used to top up the upcoming pKVM heap allocator. Note that the generic kvm_hyp_memcache does not account for the allocated memory. This is expected: donations to the heap allocator are shared and recycled, they cannot be accounted for a specific VM. Signed-off-by: Vincent Donnefort Reviewed-by: Fuad Tabba diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index bae2c4f92ef5..caea8e9986d1 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -91,9 +91,22 @@ struct kvm_hyp_memcache { struct pkvm_mapping *mapping; /* only used from EL1 */ #define HYP_MEMCACHE_ACCOUNT_STAGE2 BIT(1) +#define HYP_MEMCACHE_ACCOUNT_KMEMCG BIT(2) unsigned long flags; }; +static inline void init_hyp_memcache(struct kvm_hyp_memcache *mc) +{ + memset(mc, 0, sizeof(*mc)); + mc->mapping = ZERO_SIZE_PTR; /* Prevent allocation, solely useful for stage2 memcache */ +} + +static inline void init_hyp_stage2_memcache(struct kvm_hyp_memcache *mc) +{ + memset(mc, 0, sizeof(*mc)); + mc->flags = HYP_MEMCACHE_ACCOUNT_STAGE2 | HYP_MEMCACHE_ACCOUNT_KMEMCG; +} + static inline void push_hyp_memcache(struct kvm_hyp_memcache *mc, phys_addr_t *p, phys_addr_t (*to_pa)(void *virt)) diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 6c941aaa10c6..1e37f2f56c68 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1160,8 +1160,10 @@ static void *hyp_mc_alloc_fn(void *mc) { struct kvm_hyp_memcache *memcache = mc; void *addr; + gfp_t gfp; - addr = (void *)__get_free_page(GFP_KERNEL_ACCOUNT); + gfp = memcache->flags & HYP_MEMCACHE_ACCOUNT_KMEMCG ? GFP_KERNEL_ACCOUNT : GFP_KERNEL; + addr = (void *)__get_free_page(gfp); if (addr && memcache->flags & HYP_MEMCACHE_ACCOUNT_STAGE2) kvm_account_pgtable_pages(addr, 1); diff --git a/arch/arm64/kvm/pkvm.c b/arch/arm64/kvm/pkvm.c index 428723b1b0f5..d2681da0b629 100644 --- a/arch/arm64/kvm/pkvm.c +++ b/arch/arm64/kvm/pkvm.c @@ -111,7 +111,7 @@ static int __pkvm_create_hyp_vcpu(struct kvm_vcpu *vcpu) void *hyp_vcpu; int ret; - vcpu->arch.pkvm_memcache.flags |= HYP_MEMCACHE_ACCOUNT_STAGE2; + init_hyp_stage2_memcache(&vcpu->arch.pkvm_memcache); hyp_vcpu = alloc_pages_exact(hyp_vcpu_sz, GFP_KERNEL_ACCOUNT); if (!hyp_vcpu) @@ -172,7 +172,7 @@ static int __pkvm_create_hyp_vm(struct kvm *kvm) goto free_vm; kvm->arch.pkvm.is_created = true; - kvm->arch.pkvm.stage2_teardown_mc.flags |= HYP_MEMCACHE_ACCOUNT_STAGE2; + init_hyp_stage2_memcache(&kvm->arch.pkvm.stage2_teardown_mc); kvm_account_pgtable_pages(pgd, pgd_sz / PAGE_SIZE); return 0; -- 2.55.0.229.g6434b31f56-goog