From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 2B30E279904; Mon, 14 Jul 2025 22:15:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752531354; cv=none; b=HBtilVLdXU04om/85cxWugFnMHhthK8PKR3j8CmKz2Dr+vSknmM83arFUvNfnAy0OVCoATZ7KLjral0nhT3l3xW9QRxicl+pRXoK9GjGmwn987eMSEq/BuZcvMmBr23UwrT5GyeDRx5BG7CdiYeXPZSPDyxzCPWP4U45YsGWYig= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752531354; c=relaxed/simple; bh=dumwlVQAuaRbcn1p/IF4QNNVcpVnsy76a7SVLjV8Q3o=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=HkVDGH4qSwo313a1SgI+NZB9ETBsChtZh7ZvfFoLUtsDmodHiiV5CXz/G2j5yZ7FIWxMPZdKb0bQodO6bjc2KU0w47ue9hqCuwrqKv48uBSuSWlQP3nummFW7Ctg1ueSCp0IOytgzDtwXefaFi4g7wLMR578FObSxoeTmp54ZWo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=qc//hMsk; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="qc//hMsk" Received: from romank-3650.corp.microsoft.com (unknown [131.107.160.188]) by linux.microsoft.com (Postfix) with ESMTPSA id 3727B201A4CD; Mon, 14 Jul 2025 15:15:50 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 3727B201A4CD DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1752531350; bh=42IHhrO4islY3PvMR+vhbbQVAyXFdhkMLiuZuOP40Cg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qc//hMskvHvj8KLR89RpfUaEbmkkZGUIf8gaOC7XYOXh5/9hyBBP3jbi8m285N1jz mwzXPdYcyzVN65THd0VRgoxt8y0bCyVUoIBb9wqzM8JrZx8dQubWVO1IKu+4/a33UQ raUdHqkePqBkkxL5NvpfH9N0W3IN45QbFr8P3e1s= From: Roman Kisel To: alok.a.tiwari@oracle.com, arnd@arndb.de, bp@alien8.de, corbet@lwn.net, dave.hansen@linux.intel.com, decui@microsoft.com, haiyangz@microsoft.com, hpa@zytor.com, kys@microsoft.com, mhklinux@outlook.com, mingo@redhat.com, rdunlap@infradead.org, tglx@linutronix.de, Tianyu.Lan@microsoft.com, wei.liu@kernel.org, linux-arch@vger.kernel.org, linux-coco@lists.linux.dev, linux-doc@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org Cc: apais@microsoft.com, benhill@microsoft.com, bperkins@microsoft.com, sunilmut@microsoft.com Subject: [PATCH hyperv-next v4 12/16] Drivers: hv: Allocate encrypted buffers when requested Date: Mon, 14 Jul 2025 15:15:41 -0700 Message-ID: <20250714221545.5615-13-romank@linux.microsoft.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250714221545.5615-1-romank@linux.microsoft.com> References: <20250714221545.5615-1-romank@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Confidential VMBus is built around using buffers not shared with the host. Support allocating encrypted buffers when requested. Signed-off-by: Roman Kisel --- drivers/hv/channel.c | 49 +++++++++++++++++++++++---------------- drivers/hv/hyperv_vmbus.h | 3 ++- drivers/hv/ring_buffer.c | 5 ++-- 3 files changed, 34 insertions(+), 23 deletions(-) diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c index 35f26fa1ffe7..051eeba800f2 100644 --- a/drivers/hv/channel.c +++ b/drivers/hv/channel.c @@ -443,20 +443,23 @@ static int __vmbus_establish_gpadl(struct vmbus_channel *channel, return ret; } - /* - * Set the "decrypted" flag to true for the set_memory_decrypted() - * success case. In the failure case, the encryption state of the - * memory is unknown. Leave "decrypted" as true to ensure the - * memory will be leaked instead of going back on the free list. - */ - gpadl->decrypted = true; - ret = set_memory_decrypted((unsigned long)kbuffer, - PFN_UP(size)); - if (ret) { - dev_warn(&channel->device_obj->device, - "Failed to set host visibility for new GPADL %d.\n", - ret); - return ret; + gpadl->decrypted = !((channel->co_external_memory && type == HV_GPADL_BUFFER) || + (channel->co_ring_buffer && type == HV_GPADL_RING)); + if (gpadl->decrypted) { + /* + * The "decrypted" flag being true assumes that set_memory_decrypted() succeeds. + * But if it fails, the encryption state of the memory is unknown. In that case, + * leave "decrypted" as true to ensure the memory is leaked instead of going back + * on the free list. + */ + ret = set_memory_decrypted((unsigned long)kbuffer, + PFN_UP(size)); + if (ret) { + dev_warn(&channel->device_obj->device, + "Failed to set host visibility for new GPADL %d.\n", + ret); + return ret; + } } init_completion(&msginfo->waitevent); @@ -544,8 +547,10 @@ static int __vmbus_establish_gpadl(struct vmbus_channel *channel, * left as true so the memory is leaked instead of being * put back on the free list. */ - if (!set_memory_encrypted((unsigned long)kbuffer, PFN_UP(size))) - gpadl->decrypted = false; + if (gpadl->decrypted) { + if (!set_memory_encrypted((unsigned long)kbuffer, PFN_UP(size))) + gpadl->decrypted = false; + } } return ret; @@ -676,12 +681,13 @@ static int __vmbus_open(struct vmbus_channel *newchannel, goto error_clean_ring; err = hv_ringbuffer_init(&newchannel->outbound, - page, send_pages, 0); + page, send_pages, 0, newchannel->co_ring_buffer); if (err) goto error_free_gpadl; err = hv_ringbuffer_init(&newchannel->inbound, &page[send_pages], - recv_pages, newchannel->max_pkt_size); + recv_pages, newchannel->max_pkt_size, + newchannel->co_ring_buffer); if (err) goto error_free_gpadl; @@ -862,8 +868,11 @@ int vmbus_teardown_gpadl(struct vmbus_channel *channel, struct vmbus_gpadl *gpad kfree(info); - ret = set_memory_encrypted((unsigned long)gpadl->buffer, - PFN_UP(gpadl->size)); + if (gpadl->decrypted) + ret = set_memory_encrypted((unsigned long)gpadl->buffer, + PFN_UP(gpadl->size)); + else + ret = 0; if (ret) pr_warn("Fail to set mem host visibility in GPADL teardown %d.\n", ret); diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h index 2873703d08a9..beae68a70939 100644 --- a/drivers/hv/hyperv_vmbus.h +++ b/drivers/hv/hyperv_vmbus.h @@ -200,7 +200,8 @@ extern int hv_synic_cleanup(unsigned int cpu); void hv_ringbuffer_pre_init(struct vmbus_channel *channel); int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info, - struct page *pages, u32 pagecnt, u32 max_pkt_size); + struct page *pages, u32 pagecnt, u32 max_pkt_size, + bool confidential); void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info); diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c index 3c9b02471760..05c2cd42fc75 100644 --- a/drivers/hv/ring_buffer.c +++ b/drivers/hv/ring_buffer.c @@ -183,7 +183,8 @@ void hv_ringbuffer_pre_init(struct vmbus_channel *channel) /* Initialize the ring buffer. */ int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info, - struct page *pages, u32 page_cnt, u32 max_pkt_size) + struct page *pages, u32 page_cnt, u32 max_pkt_size, + bool confidential) { struct page **pages_wraparound; int i; @@ -207,7 +208,7 @@ int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info, ring_info->ring_buffer = (struct hv_ring_buffer *) vmap(pages_wraparound, page_cnt * 2 - 1, VM_MAP, - pgprot_decrypted(PAGE_KERNEL)); + confidential ? PAGE_KERNEL : pgprot_decrypted(PAGE_KERNEL)); kfree(pages_wraparound); if (!ring_info->ring_buffer) -- 2.43.0