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* Mon Sep 09 2019 Danilo Cesar Lemes de Paula <ddepaula@redhat.com> - 4.1.0-8.el8 

- kvm-migration-Do-not-re-read-the-clock-on-pre_save-in-ca.patch [bz#1747836]
- kvm-ehci-fix-queue-dev-null-ptr-dereference.patch [bz#1746790]
- kvm-spapr-Use-SHUTDOWN_CAUSE_SUBSYSTEM_RESET-for-CAS-reb.patch [bz#1743477]
- kvm-file-posix-Handle-undetectable-alignment.patch [bz#1749134]
- kvm-block-posix-Always-allocate-the-first-block.patch [bz#1749134]
- kvm-iotests-Test-allocate_first_block-with-O_DIRECT.patch [bz#1749134]
- Resolves: bz#1743477
  (Since bd94bc06479a "spapr: change default interrupt mode to 'dual'", QEMU resets the machine to select the appropriate interrupt controller. And -no-reboot prevents that.)
- Resolves: bz#1746790
  (qemu core dump while migrate from RHEL7.6 to RHEL8.1)
- Resolves: bz#1747836
  (Call traces after guest migration due to incorrect handling of the timebase)
- Resolves: bz#1749134
  (I/O error when virtio-blk disk is backed by a raw image on 4k disk)
This commit is contained in:
Danilo C. L. de Paula 2019-09-09 19:17:47 +01:00
parent 1442ce8243
commit 1523562e21
7 changed files with 864 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

386
kvm-block-posix-Always-allocate-the-first-block.patch Normal file
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@ -0,0 +1,386 @@
From 58dc8ae23325384b0d9494d203254dc2f6a99255 Mon Sep 17 00:00:00 2001
From: Max Reitz <mreitz@redhat.com>
Date: Mon, 9 Sep 2019 07:38:21 +0100
Subject: [PATCH 5/6] block: posix: Always allocate the first block
RH-Author: Max Reitz <mreitz@redhat.com>
Message-id: <20190909073822.26191-3-mreitz@redhat.com>
Patchwork-id: 90333
O-Subject: [RHEL-AV-8.1.0 qemu-kvm PATCH 2/3] block: posix: Always allocate the first block
Bugzilla: 1749134
RH-Acked-by: David Hildenbrand <david@redhat.com>
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Kevin Wolf <kwolf@redhat.com>
From: Nir Soffer <nirsof@gmail.com>
When creating an image with preallocation "off" or "falloc", the first
block of the image is typically not allocated. When using Gluster
storage backed by XFS filesystem, reading this block using direct I/O
succeeds regardless of request length, fooling alignment detection.
In this case we fallback to a safe value (4096) instead of the optimal
value (512), which may lead to unneeded data copying when aligning
requests. Allocating the first block avoids the fallback.
Since we allocate the first block even with preallocation=off, we no
longer create images with zero disk size:
$ ./qemu-img create -f raw test.raw 1g
Formatting 'test.raw', fmt=raw size=1073741824
$ ls -lhs test.raw
4.0K -rw-r--r--. 1 nsoffer nsoffer 1.0G Aug 16 23:48 test.raw
And converting the image requires additional cluster:
$ ./qemu-img measure -f raw -O qcow2 test.raw
required size: 458752
fully allocated size: 1074135040
When using format like vmdk with multiple files per image, we allocate
one block per file:
$ ./qemu-img create -f vmdk -o subformat=twoGbMaxExtentFlat test.vmdk 4g
Formatting 'test.vmdk', fmt=vmdk size=4294967296 compat6=off hwversion=undefined subformat=twoGbMaxExtentFlat
$ ls -lhs test*.vmdk
4.0K -rw-r--r--. 1 nsoffer nsoffer 2.0G Aug 27 03:23 test-f001.vmdk
4.0K -rw-r--r--. 1 nsoffer nsoffer 2.0G Aug 27 03:23 test-f002.vmdk
4.0K -rw-r--r--. 1 nsoffer nsoffer 353 Aug 27 03:23 test.vmdk
I did quick performance test for copying disks with qemu-img convert to
new raw target image to Gluster storage with sector size of 512 bytes:
for i in $(seq 10); do
rm -f dst.raw
sleep 10
time ./qemu-img convert -f raw -O raw -t none -T none src.raw dst.raw
done
Here is a table comparing the total time spent:
Type Before(s) After(s) Diff(%)
---------------------------------------
real 530.028 469.123 -11.4
user 17.204 10.768 -37.4
sys 17.881 7.011 -60.7
We can see very clear improvement in CPU usage.
Signed-off-by: Nir Soffer <nsoffer@redhat.com>
Message-id: 20190827010528.8818-2-nsoffer@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
(cherry picked from commit 3a20013fbb26d2a1bd11ef148eefdb1508783787)
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
---
block/file-posix.c | 51 ++++++++++++++++++++++++++++++++++++++++
tests/qemu-iotests/059.out | 2 +-
tests/qemu-iotests/150.out | 11 ---------
tests/qemu-iotests/150.out.qcow2 | 11 +++++++++
tests/qemu-iotests/150.out.raw | 12 ++++++++++
tests/qemu-iotests/175 | 19 ++++++++++-----
tests/qemu-iotests/175.out | 8 +++----
tests/qemu-iotests/178.out.qcow2 | 4 ++--
tests/qemu-iotests/221.out | 12 ++++++----
tests/qemu-iotests/253.out | 12 ++++++----
10 files changed, 110 insertions(+), 32 deletions(-)
delete mode 100644 tests/qemu-iotests/150.out
create mode 100644 tests/qemu-iotests/150.out.qcow2
create mode 100644 tests/qemu-iotests/150.out.raw
diff --git a/block/file-posix.c b/block/file-posix.c
index b8b4dad..8ea9889 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -1749,6 +1749,43 @@ static int handle_aiocb_discard(void *opaque)
return ret;
}
+/*
+ * Help alignment probing by allocating the first block.
+ *
+ * When reading with direct I/O from unallocated area on Gluster backed by XFS,
+ * reading succeeds regardless of request length. In this case we fallback to
+ * safe alignment which is not optimal. Allocating the first block avoids this
+ * fallback.
+ *
+ * fd may be opened with O_DIRECT, but we don't know the buffer alignment or
+ * request alignment, so we use safe values.
+ *
+ * Returns: 0 on success, -errno on failure. Since this is an optimization,
+ * caller may ignore failures.
+ */
+static int allocate_first_block(int fd, size_t max_size)
+{
+ size_t write_size = (max_size < MAX_BLOCKSIZE)
+ ? BDRV_SECTOR_SIZE
+ : MAX_BLOCKSIZE;
+ size_t max_align = MAX(MAX_BLOCKSIZE, getpagesize());
+ void *buf;
+ ssize_t n;
+ int ret;
+
+ buf = qemu_memalign(max_align, write_size);
+ memset(buf, 0, write_size);
+
+ do {
+ n = pwrite(fd, buf, write_size, 0);
+ } while (n == -1 && errno == EINTR);
+
+ ret = (n == -1) ? -errno : 0;
+
+ qemu_vfree(buf);
+ return ret;
+}
+
static int handle_aiocb_truncate(void *opaque)
{
RawPosixAIOData *aiocb = opaque;
@@ -1788,6 +1825,17 @@ static int handle_aiocb_truncate(void *opaque)
/* posix_fallocate() doesn't set errno. */
error_setg_errno(errp, -result,
"Could not preallocate new data");
+ } else if (current_length == 0) {
+ /*
+ * posix_fallocate() uses fallocate() if the filesystem
+ * supports it, or fallback to manually writing zeroes. If
+ * fallocate() was used, unaligned reads from the fallocated
+ * area in raw_probe_alignment() will succeed, hence we need to
+ * allocate the first block.
+ *
+ * Optimize future alignment probing; ignore failures.
+ */
+ allocate_first_block(fd, offset);
}
} else {
result = 0;
@@ -1849,6 +1897,9 @@ static int handle_aiocb_truncate(void *opaque)
if (ftruncate(fd, offset) != 0) {
result = -errno;
error_setg_errno(errp, -result, "Could not resize file");
+ } else if (current_length == 0 && offset > current_length) {
+ /* Optimize future alignment probing; ignore failures. */
+ allocate_first_block(fd, offset);
}
return result;
default:
diff --git a/tests/qemu-iotests/059.out b/tests/qemu-iotests/059.out
index 4fab42a..fe3f861 100644
--- a/tests/qemu-iotests/059.out
+++ b/tests/qemu-iotests/059.out
@@ -27,7 +27,7 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824000 subformat=twoGbMax
image: TEST_DIR/t.vmdk
file format: vmdk
virtual size: 0.977 TiB (1073741824000 bytes)
-disk size: 16 KiB
+disk size: 1.97 MiB
Format specific information:
cid: XXXXXXXX
parent cid: XXXXXXXX
diff --git a/tests/qemu-iotests/150.out b/tests/qemu-iotests/150.out
deleted file mode 100644
index 2a54e8d..0000000
--- a/tests/qemu-iotests/150.out
+++ /dev/null
@@ -1,11 +0,0 @@
-QA output created by 150
-
-=== Mapping sparse conversion ===
-
-Offset Length File
-
-=== Mapping non-sparse conversion ===
-
-Offset Length File
-0 0x100000 TEST_DIR/t.IMGFMT
-*** done
diff --git a/tests/qemu-iotests/150.out.qcow2 b/tests/qemu-iotests/150.out.qcow2
new file mode 100644
index 0000000..2a54e8d
--- /dev/null
+++ b/tests/qemu-iotests/150.out.qcow2
@@ -0,0 +1,11 @@
+QA output created by 150
+
+=== Mapping sparse conversion ===
+
+Offset Length File
+
+=== Mapping non-sparse conversion ===
+
+Offset Length File
+0 0x100000 TEST_DIR/t.IMGFMT
+*** done
diff --git a/tests/qemu-iotests/150.out.raw b/tests/qemu-iotests/150.out.raw
new file mode 100644
index 0000000..3cdc772
--- /dev/null
+++ b/tests/qemu-iotests/150.out.raw
@@ -0,0 +1,12 @@
+QA output created by 150
+
+=== Mapping sparse conversion ===
+
+Offset Length File
+0 0x1000 TEST_DIR/t.IMGFMT
+
+=== Mapping non-sparse conversion ===
+
+Offset Length File
+0 0x100000 TEST_DIR/t.IMGFMT
+*** done
diff --git a/tests/qemu-iotests/175 b/tests/qemu-iotests/175
index 51e62c8..7ba28b3 100755
--- a/tests/qemu-iotests/175
+++ b/tests/qemu-iotests/175
@@ -37,14 +37,16 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
# the file size. This function hides the resulting difference in the
# stat -c '%b' output.
# Parameter 1: Number of blocks an empty file occupies
-# Parameter 2: Image size in bytes
+# Parameter 2: Minimal number of blocks in an image
+# Parameter 3: Image size in bytes
_filter_blocks()
{
extra_blocks=$1
- img_size=$2
+ min_blocks=$2
+ img_size=$3
- sed -e "s/blocks=$extra_blocks\\(\$\\|[^0-9]\\)/nothing allocated/" \
- -e "s/blocks=$((extra_blocks + img_size / 512))\\(\$\\|[^0-9]\\)/everything allocated/"
+ sed -e "s/blocks=$min_blocks\\(\$\\|[^0-9]\\)/min allocation/" \
+ -e "s/blocks=$((extra_blocks + img_size / 512))\\(\$\\|[^0-9]\\)/max allocation/"
}
# get standard environment, filters and checks
@@ -60,16 +62,21 @@ size=$((1 * 1024 * 1024))
touch "$TEST_DIR/empty"
extra_blocks=$(stat -c '%b' "$TEST_DIR/empty")
+# We always write the first byte; check how many blocks this filesystem
+# allocates to match empty image alloation.
+printf "\0" > "$TEST_DIR/empty"
+min_blocks=$(stat -c '%b' "$TEST_DIR/empty")
+
echo
echo "== creating image with default preallocation =="
_make_test_img $size | _filter_imgfmt
-stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $size
+stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $min_blocks $size
for mode in off full falloc; do
echo
echo "== creating image with preallocation $mode =="
IMGOPTS=preallocation=$mode _make_test_img $size | _filter_imgfmt
- stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $size
+ stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $min_blocks $size
done
# success, all done
diff --git a/tests/qemu-iotests/175.out b/tests/qemu-iotests/175.out
index 6d9a5ed..263e521 100644
--- a/tests/qemu-iotests/175.out
+++ b/tests/qemu-iotests/175.out
@@ -2,17 +2,17 @@ QA output created by 175
== creating image with default preallocation ==
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576
-size=1048576, nothing allocated
+size=1048576, min allocation
== creating image with preallocation off ==
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 preallocation=off
-size=1048576, nothing allocated
+size=1048576, min allocation
== creating image with preallocation full ==
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 preallocation=full
-size=1048576, everything allocated
+size=1048576, max allocation
== creating image with preallocation falloc ==
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 preallocation=falloc
-size=1048576, everything allocated
+size=1048576, max allocation
*** done
diff --git a/tests/qemu-iotests/178.out.qcow2 b/tests/qemu-iotests/178.out.qcow2
index 55a8dc9..9e7d8c4 100644
--- a/tests/qemu-iotests/178.out.qcow2
+++ b/tests/qemu-iotests/178.out.qcow2
@@ -101,7 +101,7 @@ converted image file size in bytes: 196608
== raw input image with data (human) ==
Formatting 'TEST_DIR/t.qcow2', fmt=IMGFMT size=1073741824
-required size: 393216
+required size: 458752
fully allocated size: 1074135040
wrote 512/512 bytes at offset 512
512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
@@ -257,7 +257,7 @@ converted image file size in bytes: 196608
Formatting 'TEST_DIR/t.qcow2', fmt=IMGFMT size=1073741824
{
- "required": 393216,
+ "required": 458752,
"fully-allocated": 1074135040
}
wrote 512/512 bytes at offset 512
diff --git a/tests/qemu-iotests/221.out b/tests/qemu-iotests/221.out
index 9f9dd52..dca024a 100644
--- a/tests/qemu-iotests/221.out
+++ b/tests/qemu-iotests/221.out
@@ -3,14 +3,18 @@ QA output created by 221
=== Check mapping of unaligned raw image ===
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=65537
-[{ "start": 0, "length": 66048, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
-[{ "start": 0, "length": 66048, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 61952, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 61952, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
wrote 1/1 bytes at offset 65536
1 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-[{ "start": 0, "length": 65536, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 61440, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
{ "start": 65536, "length": 1, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
{ "start": 65537, "length": 511, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
-[{ "start": 0, "length": 65536, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 61440, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
{ "start": 65536, "length": 1, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
{ "start": 65537, "length": 511, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
*** done
diff --git a/tests/qemu-iotests/253.out b/tests/qemu-iotests/253.out
index 607c0ba..3d08b30 100644
--- a/tests/qemu-iotests/253.out
+++ b/tests/qemu-iotests/253.out
@@ -3,12 +3,16 @@ QA output created by 253
=== Check mapping of unaligned raw image ===
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048575
-[{ "start": 0, "length": 1048576, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
-[{ "start": 0, "length": 1048576, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 1044480, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 1044480, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
wrote 65535/65535 bytes at offset 983040
63.999 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-[{ "start": 0, "length": 983040, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 978944, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
{ "start": 983040, "length": 65536, "depth": 0, "zero": false, "data": true, "offset": OFFSET}]
-[{ "start": 0, "length": 983040, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 978944, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
{ "start": 983040, "length": 65536, "depth": 0, "zero": false, "data": true, "offset": OFFSET}]
*** done
--
1.8.3.1

50
kvm-ehci-fix-queue-dev-null-ptr-dereference.patch Normal file
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@ -0,0 +1,50 @@
From 0b38614471dbc44b87a1d2449e602df50c3ff535 Mon Sep 17 00:00:00 2001
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Date: Thu, 5 Sep 2019 08:50:37 +0100
Subject: [PATCH 2/6] ehci: fix queue->dev null ptr dereference
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
RH-Author: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: <20190905085037.5648-2-dgilbert@redhat.com>
Patchwork-id: 90288
O-Subject: [RHEL-AV-8.1 qemu-kvm PATCH 1/1] ehci: fix queue->dev null ptr dereference
Bugzilla: 1746790
RH-Acked-by: Peter Xu <peterx@redhat.com>
RH-Acked-by: Philippe Mathieu-Daudé <philmd@redhat.com>
RH-Acked-by: Juan Quintela <quintela@redhat.com>
From: Gerd Hoffmann <kraxel@redhat.com>
In case we don't have a device for an active queue, just skip
processing the queue (same we do for inactive queues) and log
a guest bug.
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Message-id: 20190821085319.13711-1-kraxel@redhat.com
(cherry picked from commit 1be344b7ad25d572dadeee46d80f0103354352b2)
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
---
hw/usb/hcd-ehci.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c
index 62dab05..5f089f3 100644
--- a/hw/usb/hcd-ehci.c
+++ b/hw/usb/hcd-ehci.c
@@ -1834,6 +1834,9 @@ static int ehci_state_fetchqtd(EHCIQueue *q)
ehci_set_state(q->ehci, q->async, EST_EXECUTING);
break;
}
+ } else if (q->dev == NULL) {
+ ehci_trace_guest_bug(q->ehci, "no device attached to queue");
+ ehci_set_state(q->ehci, q->async, EST_HORIZONTALQH);
} else {
p = ehci_alloc_packet(q);
p->qtdaddr = q->qtdaddr;
--
1.8.3.1

129
kvm-file-posix-Handle-undetectable-alignment.patch Normal file
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@ -0,0 +1,129 @@
From 790cebc2a1d8de8d93b2a2a0ef19e31c767f4f1c Mon Sep 17 00:00:00 2001
From: Max Reitz <mreitz@redhat.com>
Date: Mon, 9 Sep 2019 07:38:20 +0100
Subject: [PATCH 4/6] file-posix: Handle undetectable alignment
RH-Author: Max Reitz <mreitz@redhat.com>
Message-id: <20190909073822.26191-2-mreitz@redhat.com>
Patchwork-id: 90332
O-Subject: [RHEL-AV-8.1.0 qemu-kvm PATCH 1/3] file-posix: Handle undetectable alignment
Bugzilla: 1749134
RH-Acked-by: David Hildenbrand <david@redhat.com>
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Kevin Wolf <kwolf@redhat.com>
From: Nir Soffer <nirsof@gmail.com>
In some cases buf_align or request_alignment cannot be detected:
1. With Gluster, buf_align cannot be detected since the actual I/O is
done on Gluster server, and qemu buffer alignment does not matter.
Since we don't have alignment requirement, buf_align=1 is the best
value.
2. With local XFS filesystem, buf_align cannot be detected if reading
from unallocated area. In this we must align the buffer, but we don't
know what is the correct size. Using the wrong alignment results in
I/O error.
3. With Gluster backed by XFS, request_alignment cannot be detected if
reading from unallocated area. In this case we need to use the
correct alignment, and failing to do so results in I/O errors.
4. With NFS, the server does not use direct I/O, so both buf_align cannot
be detected. In this case we don't need any alignment so we can use
buf_align=1 and request_alignment=1.
These cases seems to work when storage sector size is 512 bytes, because
the current code starts checking align=512. If the check succeeds
because alignment cannot be detected we use 512. But this does not work
for storage with 4k sector size.
To determine if we can detect the alignment, we probe first with
align=1. If probing succeeds, maybe there are no alignment requirement
(cases 1, 4) or we are probing unallocated area (cases 2, 3). Since we
don't have any way to tell, we treat this as undetectable alignment. If
probing with align=1 fails with EINVAL, but probing with one of the
expected alignments succeeds, we know that we found a working alignment.
Practically the alignment requirements are the same for buffer
alignment, buffer length, and offset in file. So in case we cannot
detect buf_align, we can use request alignment. If we cannot detect
request alignment, we can fallback to a safe value. To use this logic,
we probe first request alignment instead of buf_align.
Here is a table showing the behaviour with current code (the value in
parenthesis is the optimal value).
Case Sector buf_align (opt) request_alignment (opt) result
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
---
block/file-posix.c | 36 +++++++++++++++++++++++++-----------
1 file changed, 25 insertions(+), 11 deletions(-)
diff --git a/block/file-posix.c b/block/file-posix.c
index 4479cc7..b8b4dad 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -323,6 +323,7 @@ static void raw_probe_alignment(BlockDriverState *bs, int fd, Error **errp)
BDRVRawState *s = bs->opaque;
char *buf;
size_t max_align = MAX(MAX_BLOCKSIZE, getpagesize());
+ size_t alignments[] = {1, 512, 1024, 2048, 4096};
/* For SCSI generic devices the alignment is not really used.
With buffered I/O, we don't have any restrictions. */
@@ -349,25 +350,38 @@ static void raw_probe_alignment(BlockDriverState *bs, int fd, Error **errp)
}
#endif
- /* If we could not get the sizes so far, we can only guess them */
- if (!s->buf_align) {
+ /*
+ * If we could not get the sizes so far, we can only guess them. First try
+ * to detect request alignment, since it is more likely to succeed. Then
+ * try to detect buf_align, which cannot be detected in some cases (e.g.
+ * Gluster). If buf_align cannot be detected, we fallback to the value of
+ * request_alignment.
+ */
+
+ if (!bs->bl.request_alignment) {
+ int i;
size_t align;
- buf = qemu_memalign(max_align, 2 * max_align);
- for (align = 512; align <= max_align; align <<= 1) {
- if (raw_is_io_aligned(fd, buf + align, max_align)) {
- s->buf_align = align;
+ buf = qemu_memalign(max_align, max_align);
+ for (i = 0; i < ARRAY_SIZE(alignments); i++) {
+ align = alignments[i];
+ if (raw_is_io_aligned(fd, buf, align)) {
+ /* Fallback to safe value. */
+ bs->bl.request_alignment = (align != 1) ? align : max_align;
break;
}
}
qemu_vfree(buf);
}
- if (!bs->bl.request_alignment) {
+ if (!s->buf_align) {
+ int i;
size_t align;
- buf = qemu_memalign(s->buf_align, max_align);
- for (align = 512; align <= max_align; align <<= 1) {
- if (raw_is_io_aligned(fd, buf, align)) {
- bs->bl.request_alignment = align;
+ buf = qemu_memalign(max_align, 2 * max_align);
+ for (i = 0; i < ARRAY_SIZE(alignments); i++) {
+ align = alignments[i];
+ if (raw_is_io_aligned(fd, buf + align, max_align)) {
+ /* Fallback to request_aligment. */
+ s->buf_align = (align != 1) ? align : bs->bl.request_alignment;
break;
}
}
--
1.8.3.1

109
kvm-iotests-Test-allocate_first_block-with-O_DIRECT.patch Normal file
View File

@ -0,0 +1,109 @@
From b261b31812a3e89a9104fb33bb2339b1742ac494 Mon Sep 17 00:00:00 2001
From: Max Reitz <mreitz@redhat.com>
Date: Mon, 9 Sep 2019 07:38:22 +0100
Subject: [PATCH 6/6] iotests: Test allocate_first_block() with O_DIRECT
RH-Author: Max Reitz <mreitz@redhat.com>
Message-id: <20190909073822.26191-4-mreitz@redhat.com>
Patchwork-id: 90334
O-Subject: [RHEL-AV-8.1.0 qemu-kvm PATCH 3/3] iotests: Test allocate_first_block() with O_DIRECT
Bugzilla: 1749134
RH-Acked-by: David Hildenbrand <david@redhat.com>
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Kevin Wolf <kwolf@redhat.com>
From: Nir Soffer <nirsof@gmail.com>
Using block_resize we can test allocate_first_block() with file
descriptor opened with O_DIRECT, ensuring that it works for any size
larger than 4096 bytes.
Testing smaller sizes is tricky as the result depends on the filesystem
used for testing. For example on NFS any size will work since O_DIRECT
does not require any alignment.
Signed-off-by: Nir Soffer <nsoffer@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190827010528.8818-3-nsoffer@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
(cherry picked from commit 7e3dc2ba9a11862d4e1a08325b9165f27a1b1e7c)
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
---
tests/qemu-iotests/175 | 28 ++++++++++++++++++++++++++++
tests/qemu-iotests/175.out | 8 ++++++++
2 files changed, 36 insertions(+)
diff --git a/tests/qemu-iotests/175 b/tests/qemu-iotests/175
index 7ba28b3..55db280 100755
--- a/tests/qemu-iotests/175
+++ b/tests/qemu-iotests/175
@@ -49,6 +49,23 @@ _filter_blocks()
-e "s/blocks=$((extra_blocks + img_size / 512))\\(\$\\|[^0-9]\\)/max allocation/"
}
+# Resize image using block_resize.
+# Parameter 1: image path
+# Parameter 2: new size
+_block_resize()
+{
+ local path=$1
+ local size=$2
+
+ $QEMU -qmp stdio -nographic -nodefaults \
+ -blockdev file,node-name=file,filename=$path,cache.direct=on \
+ <<EOF
+{'execute': 'qmp_capabilities'}
+{'execute': 'block_resize', 'arguments': {'node-name': 'file', 'size': $size}}
+{'execute': 'quit'}
+EOF
+}
+
# get standard environment, filters and checks
. ./common.rc
. ./common.filter
@@ -57,6 +74,9 @@ _supported_fmt raw
_supported_proto file
_supported_os Linux
+_default_cache_mode none
+_supported_cache_modes none directsync
+
size=$((1 * 1024 * 1024))
touch "$TEST_DIR/empty"
@@ -79,6 +99,14 @@ for mode in off full falloc; do
stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $min_blocks $size
done
+for new_size in 4096 1048576; do
+ echo
+ echo "== resize empty image with block_resize =="
+ _make_test_img 0 | _filter_imgfmt
+ _block_resize $TEST_IMG $new_size >/dev/null
+ stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $min_blocks $new_size
+done
+
# success, all done
echo "*** done"
rm -f $seq.full
diff --git a/tests/qemu-iotests/175.out b/tests/qemu-iotests/175.out
index 263e521..39c2ee0 100644
--- a/tests/qemu-iotests/175.out
+++ b/tests/qemu-iotests/175.out
@@ -15,4 +15,12 @@ size=1048576, max allocation
== creating image with preallocation falloc ==
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 preallocation=falloc
size=1048576, max allocation
+
+== resize empty image with block_resize ==
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=0
+size=4096, min allocation
+
+== resize empty image with block_resize ==
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=0
+size=1048576, min allocation
*** done
--
1.8.3.1

101
kvm-migration-Do-not-re-read-the-clock-on-pre_save-in-ca.patch Normal file
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@ -0,0 +1,101 @@
From 8b0a69f11052d271ef49db0051d79e7f1a6102be Mon Sep 17 00:00:00 2001
From: David Gibson <dgibson@redhat.com>
Date: Mon, 2 Sep 2019 04:20:32 +0100
Subject: [PATCH 1/6] migration: Do not re-read the clock on pre_save in case
of paused guest
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
RH-Author: David Gibson <dgibson@redhat.com>
Message-id: <20190902042032.25987-1-dgibson@redhat.com>
Patchwork-id: 90226
O-Subject: [RHEL-AV-8.1.0 qemu-kvm PATCH] migration: Do not re-read the clock on pre_save in case of paused guest
Bugzilla: 1747836
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Philippe Mathieu-Daudé <philmd@redhat.com>
RH-Acked-by: Laurent Vivier <lvivier@redhat.com>
From: "Maxiwell S. Garcia" <maxiwell@linux.ibm.com>
Re-read the timebase before migrate was ported from x86 commit:
6053a86fe7bd: kvmclock: reduce kvmclock difference on migration
The clock move makes the guest knows about the paused time between
the stop and migrate commands. This is an issue in an already-paused
VM because some side effects, like process stalls, could happen
after migration.
So, this patch checks the runstate of guest in the pre_save handler and
do not re-reads the timebase in case of paused state (cold migration).
Signed-off-by: Maxiwell S. Garcia <maxiwell@linux.ibm.com>
Message-Id: <20190711194702.26598-1-maxiwell@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
(cherry picked from commit d14f33976282a8744ca1bf1d64e73996c145aa3f)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1747836
Branch: rhel8/rhel-av-8.1.0/master-4.1.0
Brew: https://brewweb.engineering.redhat.com/brew/taskinfo?taskID=23282250
Testing: Booted guest with this qemu
Signed-off-by: David Gibson <dgibson@redhat.com>
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
---
hw/ppc/ppc.c | 13 +++++++++----
target/ppc/cpu-qom.h | 1 +
2 files changed, 10 insertions(+), 4 deletions(-)
diff --git a/hw/ppc/ppc.c b/hw/ppc/ppc.c
index a9e508c..8572e45 100644
--- a/hw/ppc/ppc.c
+++ b/hw/ppc/ppc.c
@@ -1008,6 +1008,8 @@ static void timebase_save(PPCTimebase *tb)
* there is no need to update it from KVM here
*/
tb->guest_timebase = ticks + first_ppc_cpu->env.tb_env->tb_offset;
+
+ tb->runstate_paused = runstate_check(RUN_STATE_PAUSED);
}
static void timebase_load(PPCTimebase *tb)
@@ -1051,9 +1053,9 @@ void cpu_ppc_clock_vm_state_change(void *opaque, int running,
}
/*
- * When migrating, read the clock just before migration,
- * so that the guest clock counts during the events
- * between:
+ * When migrating a running guest, read the clock just
+ * before migration, so that the guest clock counts
+ * during the events between:
*
* * vm_stop()
* *
@@ -1068,7 +1070,10 @@ static int timebase_pre_save(void *opaque)
{
PPCTimebase *tb = opaque;
- timebase_save(tb);
+ /* guest_timebase won't be overridden in case of paused guest */
+ if (!tb->runstate_paused) {
+ timebase_save(tb);
+ }
return 0;
}
diff --git a/target/ppc/cpu-qom.h b/target/ppc/cpu-qom.h
index be9b4c3..5fbcdee 100644
--- a/target/ppc/cpu-qom.h
+++ b/target/ppc/cpu-qom.h
@@ -201,6 +201,7 @@ typedef struct PowerPCCPUClass {
typedef struct PPCTimebase {
uint64_t guest_timebase;
int64_t time_of_the_day_ns;
+ bool runstate_paused;
} PPCTimebase;
extern const struct VMStateDescription vmstate_ppc_timebase;
--
1.8.3.1

60
kvm-spapr-Use-SHUTDOWN_CAUSE_SUBSYSTEM_RESET-for-CAS-reb.patch Normal file
View File

@ -0,0 +1,60 @@
From c8d3479746b17fcdf56b8afb3eccdba2c14578e8 Mon Sep 17 00:00:00 2001
From: David Gibson <dgibson@redhat.com>
Date: Fri, 6 Sep 2019 03:58:36 +0100
Subject: [PATCH 3/6] spapr: Use SHUTDOWN_CAUSE_SUBSYSTEM_RESET for CAS reboots
RH-Author: David Gibson <dgibson@redhat.com>
Message-id: <20190906035836.23689-1-dgibson@redhat.com>
Patchwork-id: 90293
O-Subject: [RHEL-AV-8.1.0 qemu-kvm PATCH] spapr: Use SHUTDOWN_CAUSE_SUBSYSTEM_RESET for CAS reboots
Bugzilla: 1743477
RH-Acked-by: Laurent Vivier <lvivier@redhat.com>
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Danilo de Paula <ddepaula@redhat.com>
From: David Gibson <david@gibson.dropbear.id.au>
The sPAPR platform includes feature negotiation between the guest and
platform. That sometimes requires reconfiguring the virtual hardware, and
in some cases that is a complex enough process that we trigger a system
reset to handle it. That interacts badly with -no-reboot - we trigger the
reboot, -no-reboot means we exit and so the guest never gets to try again.
Eventually we want to get rid of CAS reboots entirely, since they're odd
and irritating for the user. But in the meantime we can fix the -no-reboot
problem by using SHUTDOWN_CAUSE_SUBSYSTEM_RESET which ignores -no-reboot
and seems to be designed for this sort of faux-reset for internal purposes
only.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
(cherry picked from commit 9146206eb26c1436c80a7c2ca1e4c5f86b27179d)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1743477
Brew: https://brewweb.engineering.redhat.com/brew/taskinfo?taskID=23395494
Branch: rhel-av-8.1.0/master-4.1.0
Testing: Started a guest and verified that -no-reboot no longer
prevents the CAS reboot to negotiate XIVE support from
completing
Signed-off-by: David Gibson <dgibson@redhat.com>
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
---
hw/ppc/spapr_hcall.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
index 6808d4c..687bb7b 100644
--- a/hw/ppc/spapr_hcall.c
+++ b/hw/ppc/spapr_hcall.c
@@ -1672,7 +1672,7 @@ static target_ulong h_client_architecture_support(PowerPCCPU *cpu,
spapr_ovec_cleanup(ov5_updates);
if (spapr->cas_reboot) {
- qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
+ qemu_system_reset_request(SHUTDOWN_CAUSE_SUBSYSTEM_RESET);
}
return H_SUCCESS;
--
1.8.3.1

30
qemu-kvm.spec
View File

@ -67,7 +67,7 @@ Obsoletes: %1-rhev
Summary: QEMU is a machine emulator and virtualizer
Name: qemu-kvm
Version: 4.1.0
Release: 7%{?dist}
Release: 8%{?dist}
# Epoch because we pushed a qemu-1.0 package. AIUI this can't ever be dropped
Epoch: 15
License: GPLv2 and GPLv2+ and CC-BY
@ -166,6 +166,18 @@ Patch41: kvm-multifd-Use-number-of-channels-as-listen-backlog.patch
Patch42: kvm-pseries-Fix-compat_pvr-on-reset.patch
# For bz#1744107 - Migration from P8(qemu4.1) to P9(qemu4.1), after migration, qemu crash on destination with error message "qemu-kvm: error while loading state for instance 0x1 of device 'cpu'"
Patch43: kvm-spapr-Set-compat-mode-in-spapr_core_plug.patch
# For bz#1747836 - Call traces after guest migration due to incorrect handling of the timebase
Patch44: kvm-migration-Do-not-re-read-the-clock-on-pre_save-in-ca.patch
# For bz#1746790 - qemu core dump while migrate from RHEL7.6 to RHEL8.1
Patch45: kvm-ehci-fix-queue-dev-null-ptr-dereference.patch
# For bz#1743477 - Since bd94bc06479a "spapr: change default interrupt mode to 'dual'", QEMU resets the machine to select the appropriate interrupt controller. And -no-reboot prevents that.
Patch46: kvm-spapr-Use-SHUTDOWN_CAUSE_SUBSYSTEM_RESET-for-CAS-reb.patch
# For bz#1749134 - I/O error when virtio-blk disk is backed by a raw image on 4k disk
Patch47: kvm-file-posix-Handle-undetectable-alignment.patch
# For bz#1749134 - I/O error when virtio-blk disk is backed by a raw image on 4k disk
Patch48: kvm-block-posix-Always-allocate-the-first-block.patch
# For bz#1749134 - I/O error when virtio-blk disk is backed by a raw image on 4k disk
Patch49: kvm-iotests-Test-allocate_first_block-with-O_DIRECT.patch
BuildRequires: wget
BuildRequires: rpm-build
@ -1107,6 +1119,22 @@ useradd -r -u 107 -g qemu -G kvm -d / -s /sbin/nologin \
%changelog
* Mon Sep 09 2019 Danilo Cesar Lemes de Paula <ddepaula@redhat.com> - 4.1.0-8.el8
- kvm-migration-Do-not-re-read-the-clock-on-pre_save-in-ca.patch [bz#1747836]
- kvm-ehci-fix-queue-dev-null-ptr-dereference.patch [bz#1746790]
- kvm-spapr-Use-SHUTDOWN_CAUSE_SUBSYSTEM_RESET-for-CAS-reb.patch [bz#1743477]
- kvm-file-posix-Handle-undetectable-alignment.patch [bz#1749134]
- kvm-block-posix-Always-allocate-the-first-block.patch [bz#1749134]
- kvm-iotests-Test-allocate_first_block-with-O_DIRECT.patch [bz#1749134]
- Resolves: bz#1743477
(Since bd94bc06479a "spapr: change default interrupt mode to 'dual'", QEMU resets the machine to select the appropriate interrupt controller. And -no-reboot prevents that.)
- Resolves: bz#1746790
(qemu core dump while migrate from RHEL7.6 to RHEL8.1)
- Resolves: bz#1747836
(Call traces after guest migration due to incorrect handling of the timebase)
- Resolves: bz#1749134
(I/O error when virtio-blk disk is backed by a raw image on 4k disk)
* Fri Sep 06 2019 Danilo Cesar Lemes de Paula <ddepaula@redhat.com> - 4.1.0-7.el8
- kvm-trace-Clarify-DTrace-SystemTap-help-message.patch [bz#1516220]
- kvm-socket-Add-backlog-parameter-to-socket_listen.patch [bz#1726898]