patch 'vhost: fix guest to host physical address mapping' has been queued to stable release 20.11.5

[luca.boccassi at gmail.com]

Hi,

FYI, your patch has been queued to stable release 20.11.5

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 02/20/22. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/bluca/dpdk-stable

This queued commit can be viewed at:
https://github.com/bluca/dpdk-stable/commit/0e63db20225d30607facb5db741edd543e0d3bdf

Thanks.

Luca Boccassi

---
>From 0e63db20225d30607facb5db741edd543e0d3bdf Mon Sep 17 00:00:00 2001
From: Yuan Wang <yuanx.wang at intel.com>
Date: Mon, 17 Jan 2022 16:20:27 +0000
Subject: [PATCH] vhost: fix guest to host physical address mapping

[ upstream commit 8b764f460f168505b9335bdbd0e0fead8edbc188 ]

Async copy fails when looking up hpa in the gpa to hpa mapping table.
This happens because the gpa is matched exactly in the merged
mapping table, and the merge loses the mapping entries.
A new range comparison method is introduced to solve this issue.

Fixes: 6563cf92380a ("vhost: fix async copy on multi-page buffers")

Signed-off-by: Yuan Wang <yuanx.wang at intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin at redhat.com>
---
 lib/librte_vhost/vhost.h | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index 984c7a6f5f..36d6fdabd8 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -565,6 +565,20 @@ static __rte_always_inline int guest_page_addrcmp(const void *p1,
 	return 0;
 }
 
+static __rte_always_inline int guest_page_rangecmp(const void *p1, const void *p2)
+{
+	const struct guest_page *page1 = (const struct guest_page *)p1;
+	const struct guest_page *page2 = (const struct guest_page *)p2;
+
+	if (page1->guest_phys_addr >= page2->guest_phys_addr) {
+		if (page1->guest_phys_addr < page2->guest_phys_addr + page2->size)
+			return 0;
+		else
+			return 1;
+	} else
+		return -1;
+}
+
 static __rte_always_inline rte_iova_t
 gpa_to_first_hpa(struct virtio_net *dev, uint64_t gpa,
 	uint64_t gpa_size, uint64_t *hpa_size)
@@ -575,9 +589,9 @@ gpa_to_first_hpa(struct virtio_net *dev, uint64_t gpa,
 
 	*hpa_size = gpa_size;
 	if (dev->nr_guest_pages >= VHOST_BINARY_SEARCH_THRESH) {
-		key.guest_phys_addr = gpa & ~(dev->guest_pages[0].size - 1);
+		key.guest_phys_addr = gpa;
 		page = bsearch(&key, dev->guest_pages, dev->nr_guest_pages,
-			       sizeof(struct guest_page), guest_page_addrcmp);
+			       sizeof(struct guest_page), guest_page_rangecmp);
 		if (page) {
 			if (gpa + gpa_size <=
 					page->guest_phys_addr + page->size) {
-- 
2.30.2

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2022-02-18 12:37:41.516949670 +0000
+++ 0095-vhost-fix-guest-to-host-physical-address-mapping.patch	2022-02-18 12:37:37.826794957 +0000
@@ -1 +1 @@
-From 8b764f460f168505b9335bdbd0e0fead8edbc188 Mon Sep 17 00:00:00 2001
+From 0e63db20225d30607facb5db741edd543e0d3bdf Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit 8b764f460f168505b9335bdbd0e0fead8edbc188 ]
+
@@ -12 +13,0 @@
-Cc: stable at dpdk.org
@@ -17 +18 @@
- lib/vhost/vhost.h | 18 ++++++++++++++++--
+ lib/librte_vhost/vhost.h | 18 ++++++++++++++++--
@@ -20,5 +21,5 @@
-diff --git a/lib/vhost/vhost.h b/lib/vhost/vhost.h
-index 7085e0885c..b3f0c1d07c 100644
---- a/lib/vhost/vhost.h
-+++ b/lib/vhost/vhost.h
-@@ -587,6 +587,20 @@ static __rte_always_inline int guest_page_addrcmp(const void *p1,
+diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
+index 984c7a6f5f..36d6fdabd8 100644
+--- a/lib/librte_vhost/vhost.h
++++ b/lib/librte_vhost/vhost.h
+@@ -565,6 +565,20 @@ static __rte_always_inline int guest_page_addrcmp(const void *p1,
@@ -45 +46 @@
-@@ -597,9 +611,9 @@ gpa_to_first_hpa(struct virtio_net *dev, uint64_t gpa,
+@@ -575,9 +589,9 @@ gpa_to_first_hpa(struct virtio_net *dev, uint64_t gpa,