From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8C3F35D8E4; Mon, 11 Mar 2024 18:37:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710182269; cv=none; b=npsCq2+N2FcvudEHyHb+MazXxbiOSTTL7TTJF8zazQuvwEBraGLHxWExMvLIw1P27wTOuby6Hg0Fs5fkBJBeOsUP2EtYvjBodErfyFdbRE5FImmfhxvYv1rP4m8CEmZd4o9d8Qcc4eRTOoAutuoR7dvmfVaxfiMb9068kjohtLs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710182269; c=relaxed/simple; bh=JMIrqkXSyJesx8styDYE/rwVLPhnB+Uu7VY6ykF1GMM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rCT2YWL52ApZWSYu6c9hm5kRGpOjGTwXPp9RiACokoXl40zrhI3EGLW5DnFd2gllCEXr1Juxt4VJ1634EtHLekvdMDTAUjA+SkSOcUBwU0e2shY7YaClfEYm0l5OW8UuShlJ54Vy7xbRFydd0qJeODffaDokWgCwopozN1TQcvM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ejTwuR/b; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ejTwuR/b" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 995B8C43601; Mon, 11 Mar 2024 18:37:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1710182269; bh=JMIrqkXSyJesx8styDYE/rwVLPhnB+Uu7VY6ykF1GMM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ejTwuR/bC5NXUyJxFNffxz1T3iA/KGAhFGxeY1aO36raXS0/ibKLUR87AwWLE5in7 VXGPUqxKD8S3IobYFaGLp1JwUJyM9Vn0kbj6JhQ5eVuE6usUfP5FTz9zGJGFoor7b0 nrJoOcjY3Tk54KPheNegGc2YdCa2Ja1rnpsgErEAS8k4zGxsF0aqt+g9O28ieROn/c AQGU05qjkmwWYEVrFDUsTOWs541fPthFpdGb6Kp1nGjObVUwN9ZyCcBAYPn/LQJD37 HBvYee1gSz5TqGqnSnUkf1xdDktkrupmHdQEaVH+zBFp8Ypq0mRanx6RH5o1Buqy/S c3Q/DfhYQtZvw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Michael Kelley , "Kirill A . Shutemov" , Rick Edgecombe , Wei Liu , Sasha Levin , kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org, dave.hansen@linux.intel.com, luto@kernel.org, peterz@infradead.org, devel@linuxdriverproject.org Subject: [PATCH AUTOSEL 6.6 03/12] x86/hyperv: Use slow_virt_to_phys() in page transition hypervisor callback Date: Mon, 11 Mar 2024 14:37:17 -0400 Message-ID: <20240311183727.328187-3-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240311183727.328187-1-sashal@kernel.org> References: <20240311183727.328187-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.6.21 Content-Transfer-Encoding: 8bit From: Michael Kelley [ Upstream commit 9fef276f9f416a1e85eb48d3bd38e6018a220bf5 ] In preparation for temporarily marking pages not present during a transition between encrypted and decrypted, use slow_virt_to_phys() in the hypervisor callback. As long as the PFN is correct, slow_virt_to_phys() works even if the leaf PTE is not present. The existing functions that depend on vmalloc_to_page() all require that the leaf PTE be marked present, so they don't work. Update the comments for slow_virt_to_phys() to note this broader usage and the requirement to work even if the PTE is not marked present. Signed-off-by: Michael Kelley Acked-by: Kirill A. Shutemov Reviewed-by: Rick Edgecombe Link: https://lore.kernel.org/r/20240116022008.1023398-2-mhklinux@outlook.com Signed-off-by: Wei Liu Message-ID: <20240116022008.1023398-2-mhklinux@outlook.com> Signed-off-by: Sasha Levin --- arch/x86/hyperv/ivm.c | 12 +++++++++++- arch/x86/mm/pat/set_memory.c | 12 ++++++++---- 2 files changed, 19 insertions(+), 5 deletions(-) diff --git a/arch/x86/hyperv/ivm.c b/arch/x86/hyperv/ivm.c index 8c6bf07f7d2b8..4bf3805aa8ab5 100644 --- a/arch/x86/hyperv/ivm.c +++ b/arch/x86/hyperv/ivm.c @@ -515,6 +515,8 @@ static bool hv_vtom_set_host_visibility(unsigned long kbuffer, int pagecount, bo enum hv_mem_host_visibility visibility = enc ? VMBUS_PAGE_NOT_VISIBLE : VMBUS_PAGE_VISIBLE_READ_WRITE; u64 *pfn_array; + phys_addr_t paddr; + void *vaddr; int ret = 0; bool result = true; int i, pfn; @@ -524,7 +526,15 @@ static bool hv_vtom_set_host_visibility(unsigned long kbuffer, int pagecount, bo return false; for (i = 0, pfn = 0; i < pagecount; i++) { - pfn_array[pfn] = virt_to_hvpfn((void *)kbuffer + i * HV_HYP_PAGE_SIZE); + /* + * Use slow_virt_to_phys() because the PRESENT bit has been + * temporarily cleared in the PTEs. slow_virt_to_phys() works + * without the PRESENT bit while virt_to_hvpfn() or similar + * does not. + */ + vaddr = (void *)kbuffer + (i * HV_HYP_PAGE_SIZE); + paddr = slow_virt_to_phys(vaddr); + pfn_array[pfn] = paddr >> HV_HYP_PAGE_SHIFT; pfn++; if (pfn == HV_MAX_MODIFY_GPA_REP_COUNT || i == pagecount - 1) { diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c index bda9f129835e9..355dc8f5cb7dd 100644 --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -755,10 +755,14 @@ pmd_t *lookup_pmd_address(unsigned long address) * areas on 32-bit NUMA systems. The percpu areas can * end up in this kind of memory, for instance. * - * This could be optimized, but it is only intended to be - * used at initialization time, and keeping it - * unoptimized should increase the testing coverage for - * the more obscure platforms. + * Note that as long as the PTEs are well-formed with correct PFNs, this + * works without checking the PRESENT bit in the leaf PTE. This is unlike + * the similar vmalloc_to_page() and derivatives. Callers may depend on + * this behavior. + * + * This could be optimized, but it is only used in paths that are not perf + * sensitive, and keeping it unoptimized should increase the testing coverage + * for the more obscure platforms. */ phys_addr_t slow_virt_to_phys(void *__virt_addr) { -- 2.43.0