diff mbox series

[for-2.12] memfd: fix vhost-user-test on non-memfd capable host

Message ID 20180328121804.16203-1-marcandre.lureau@redhat.com
State New
Headers show
Series [for-2.12] memfd: fix vhost-user-test on non-memfd capable host | expand

Commit Message

Marc-André Lureau March 28, 2018, 12:18 p.m. UTC 
On RHEL7, memfd is not supported, and vhost-user-test fails:
TEST: tests/vhost-user-test... (pid=10248)
  /x86_64/vhost-user/migrate:
  qemu-system-x86_64: -object memory-backend-memfd,id=mem,size=2M,: failed to create memfd
FAIL

There is a qemu_memfd_check() to prevent running memfd path, but it
also checks for fallback implementation. Let's specialize
qemu_memfd_check() to check memfd only, while qemu_memfd_alloc_check()
checks for the qemu_memfd_alloc() API.

Reported-by: Miroslav Rezanina <mrezanin@redhat.com>
Tested-by: Miroslav Rezanina <mrezanin@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 include/qemu/memfd.h |  1 +
 hw/virtio/vhost.c    |  2 +-
 util/memfd.c         | 30 +++++++++++++++++++++++++++++-
 3 files changed, 31 insertions(+), 2 deletions(-)

Comments

no-reply@patchew.org March 31, 2018, 6:57 a.m. UTC | #1 
Hi,

This series failed docker-build@min-glib build test. Please find the testing commands and
their output below. If you have Docker installed, you can probably reproduce it
locally.

Type: series
Message-id: 20180328121804.16203-1-marcandre.lureau@redhat.com
Subject: [Qemu-devel] [PATCH for-2.12] memfd: fix vhost-user-test on non-memfd capable host

=== TEST SCRIPT BEGIN ===
#!/bin/bash
set -e
git submodule update --init dtc
# Let docker tests dump environment info
export SHOW_ENV=1
export J=8
time make docker-test-build@min-glib
=== TEST SCRIPT END ===

Updating 3c8cf5a9c21ff8782164d1def7f44bd888713384
Switched to a new branch 'test'
12b7026b1b memfd: fix vhost-user-test on non-memfd capable host

=== OUTPUT BEGIN ===
Submodule 'dtc' (git://git.qemu-project.org/dtc.git) registered for path 'dtc'
Cloning into '/var/tmp/patchew-tester-tmp-14znopuf/src/dtc'...
Submodule path 'dtc': checked out 'e54388015af1fb4bf04d0bca99caba1074d9cc42'
  BUILD   min-glib
make[1]: Entering directory '/var/tmp/patchew-tester-tmp-14znopuf/src'
  GEN     /var/tmp/patchew-tester-tmp-14znopuf/src/docker-src.2018-03-31-02.57.01.19306/qemu.tar
Cloning into '/var/tmp/patchew-tester-tmp-14znopuf/src/docker-src.2018-03-31-02.57.01.19306/qemu.tar.vroot'...
done.
Checking out files:  42% (2549/6066)   
Checking out files:  43% (2609/6066)   
Checking out files:  44% (2670/6066)   
Checking out files:  45% (2730/6066)   
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Checking out files: 100% (6066/6066)   
Checking out files: 100% (6066/6066), done.
Your branch is up-to-date with 'origin/test'.
Submodule 'dtc' (git://git.qemu-project.org/dtc.git) registered for path 'dtc'
Cloning into '/var/tmp/patchew-tester-tmp-14znopuf/src/docker-src.2018-03-31-02.57.01.19306/qemu.tar.vroot/dtc'...
Submodule path 'dtc': checked out 'e54388015af1fb4bf04d0bca99caba1074d9cc42'
Submodule 'ui/keycodemapdb' (git://git.qemu.org/keycodemapdb.git) registered for path 'ui/keycodemapdb'
Cloning into '/var/tmp/patchew-tester-tmp-14znopuf/src/docker-src.2018-03-31-02.57.01.19306/qemu.tar.vroot/ui/keycodemapdb'...
Submodule path 'ui/keycodemapdb': checked out '6b3d716e2b6472eb7189d3220552280ef3d832ce'
tar: /var/tmp/patchew-tester-tmp-14znopuf/src/docker-src.2018-03-31-02.57.01.19306/qemu.tar: Wrote only 2048 of 10240 bytes
tar: Error is not recoverable: exiting now
failed to create tar file
  COPY    RUNNER
    RUN test-build in qemu:min-glib 
tar: Unexpected EOF in archive
tar: Unexpected EOF in archive
tar: Error is not recoverable: exiting now
/var/tmp/qemu/run: line 32: prep_fail: command not found
Environment variables:
HOSTNAME=4b68edf62d68
MAKEFLAGS= -j8
J=8
CCACHE_DIR=/var/tmp/ccache
EXTRA_CONFIGURE_OPTS=
V=
SHOW_ENV=1
PATH=/usr/lib/ccache:/usr/lib64/ccache:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
PWD=/
TARGET_LIST=
SHLVL=1
HOME=/root
TEST_DIR=/tmp/qemu-test
FEATURES= dtc
DEBUG=
_=/usr/bin/env

Configure options:
--enable-werror --target-list=x86_64-softmmu,aarch64-softmmu --prefix=/tmp/qemu-test/install

ERROR: DTC (libfdt) version >= 1.4.2 not present.
       Please install the DTC (libfdt) devel package

Traceback (most recent call last):
  File "./tests/docker/docker.py", line 407, in <module>
    sys.exit(main())
  File "./tests/docker/docker.py", line 404, in main
    return args.cmdobj.run(args, argv)
  File "./tests/docker/docker.py", line 261, in run
    return Docker().run(argv, args.keep, quiet=args.quiet)
  File "./tests/docker/docker.py", line 229, in run
    quiet=quiet)
  File "./tests/docker/docker.py", line 147, in _do_check
    return subprocess.check_call(self._command + cmd, **kwargs)
  File "/usr/lib64/python2.7/subprocess.py", line 186, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['docker', 'run', '--label', 'com.qemu.instance.uuid=c4861cce34b011e8ac6652540069c830', '-u', '0', '--security-opt', 'seccomp=unconfined', '--rm', '--net=none', '-e', 'TARGET_LIST=', '-e', 'EXTRA_CONFIGURE_OPTS=', '-e', 'V=', '-e', 'J=8', '-e', 'DEBUG=', '-e', 'SHOW_ENV=1', '-e', 'CCACHE_DIR=/var/tmp/ccache', '-v', '/root/.cache/qemu-docker-ccache:/var/tmp/ccache:z', '-v', '/var/tmp/patchew-tester-tmp-14znopuf/src/docker-src.2018-03-31-02.57.01.19306:/var/tmp/qemu:z,ro', 'qemu:min-glib', '/var/tmp/qemu/run', 'test-build']' returned non-zero exit status 1
make[1]: *** [tests/docker/Makefile.include:129: docker-run] Error 1
make[1]: Leaving directory '/var/tmp/patchew-tester-tmp-14znopuf/src'
make: *** [tests/docker/Makefile.include:163: docker-run-test-build@min-glib] Error 2

real	0m48.962s
user	0m9.100s
sys	0m6.849s
=== OUTPUT END ===

Test command exited with code: 2


---
Email generated automatically by Patchew [http://patchew.org/].
Please send your feedback to patchew-devel@redhat.com
Marc-André Lureau April 4, 2018, 1:51 p.m. UTC | #2 
On Wed, Mar 28, 2018 at 2:18 PM, Marc-André Lureau
<marcandre.lureau@redhat.com> wrote:
> On RHEL7, memfd is not supported, and vhost-user-test fails:
> TEST: tests/vhost-user-test... (pid=10248)
>   /x86_64/vhost-user/migrate:
>   qemu-system-x86_64: -object memory-backend-memfd,id=mem,size=2M,: failed to create memfd
> FAIL
>
> There is a qemu_memfd_check() to prevent running memfd path, but it
> also checks for fallback implementation. Let's specialize
> qemu_memfd_check() to check memfd only, while qemu_memfd_alloc_check()
> checks for the qemu_memfd_alloc() API.
>
> Reported-by: Miroslav Rezanina <mrezanin@redhat.com>
> Tested-by: Miroslav Rezanina <mrezanin@redhat.com>
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

ping

> ---
>  include/qemu/memfd.h |  1 +
>  hw/virtio/vhost.c    |  2 +-
>  util/memfd.c         | 30 +++++++++++++++++++++++++++++-
>  3 files changed, 31 insertions(+), 2 deletions(-)
>
> diff --git a/include/qemu/memfd.h b/include/qemu/memfd.h
> index de10198ed6..49e79634da 100644
> --- a/include/qemu/memfd.h
> +++ b/include/qemu/memfd.h
> @@ -18,6 +18,7 @@
>
>  int qemu_memfd_create(const char *name, size_t size, bool hugetlb,
>                        uint64_t hugetlbsize, unsigned int seals, Error **errp);
> +bool qemu_memfd_alloc_check(void);
>  void *qemu_memfd_alloc(const char *name, size_t size, unsigned int seals,
>                         int *fd, Error **errp);
>  void qemu_memfd_free(void *ptr, size_t size, int fd);
> diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
> index 250f886acb..27c1ec5fe8 100644
> --- a/hw/virtio/vhost.c
> +++ b/hw/virtio/vhost.c
> @@ -1223,7 +1223,7 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
>          if (!(hdev->features & (0x1ULL << VHOST_F_LOG_ALL))) {
>              error_setg(&hdev->migration_blocker,
>                         "Migration disabled: vhost lacks VHOST_F_LOG_ALL feature.");
> -        } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_check()) {
> +        } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_alloc_check()) {
>              error_setg(&hdev->migration_blocker,
>                         "Migration disabled: failed to allocate shared memory");
>          }
> diff --git a/util/memfd.c b/util/memfd.c
> index 07d579ea7d..277f7211af 100644
> --- a/util/memfd.c
> +++ b/util/memfd.c
> @@ -173,7 +173,13 @@ enum {
>      MEMFD_TODO
>  };
>
> -bool qemu_memfd_check(void)
> +/**
> + * qemu_memfd_alloc_check():
> + *
> + * Check if qemu_memfd_alloc() can allocate, including using a
> + * fallback implementation when host doesn't support memfd.
> + */
> +bool qemu_memfd_alloc_check(void)
>  {
>      static int memfd_check = MEMFD_TODO;
>
> @@ -188,3 +194,25 @@ bool qemu_memfd_check(void)
>
>      return memfd_check == MEMFD_OK;
>  }
> +
> +/**
> + * qemu_memfd_check():
> + *
> + * Check if host supports memfd.
> + */
> +bool qemu_memfd_check(void)
> +{
> +    static int memfd_check = MEMFD_TODO;
> +
> +    if (memfd_check == MEMFD_TODO) {
> +        int mfd = memfd_create("test", 0);
> +        if (mfd >= 0) {
> +            memfd_check = MEMFD_OK;
> +            close(mfd);
> +        } else {
> +            memfd_check = MEMFD_KO;
> +        }
> +    }
> +
> +    return memfd_check == MEMFD_OK;
> +}
> --
> 2.17.0.rc1.1.g4c4f2b46a3
>
>
Miroslav Rezanina April 5, 2018, 3:56 a.m. UTC | #3 
On Wed, Mar 28, 2018 at 02:18:04PM +0200, Marc-André Lureau wrote:
> On RHEL7, memfd is not supported, and vhost-user-test fails:
> TEST: tests/vhost-user-test... (pid=10248)
>   /x86_64/vhost-user/migrate:
>   qemu-system-x86_64: -object memory-backend-memfd,id=mem,size=2M,: failed to create memfd
> FAIL
> 
> There is a qemu_memfd_check() to prevent running memfd path, but it
> also checks for fallback implementation. Let's specialize
> qemu_memfd_check() to check memfd only, while qemu_memfd_alloc_check()
> checks for the qemu_memfd_alloc() API.
> 
> Reported-by: Miroslav Rezanina <mrezanin@redhat.com>
> Tested-by: Miroslav Rezanina <mrezanin@redhat.com>
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---

Patch is solving failing build on RHEL 7. Needed in 2.12.

Tested-by: Miroslav Rezanina <mrezanin@redhat.com>

>  include/qemu/memfd.h |  1 +
>  hw/virtio/vhost.c    |  2 +-
>  util/memfd.c         | 30 +++++++++++++++++++++++++++++-
>  3 files changed, 31 insertions(+), 2 deletions(-)
> 
> diff --git a/include/qemu/memfd.h b/include/qemu/memfd.h
> index de10198ed6..49e79634da 100644
> --- a/include/qemu/memfd.h
> +++ b/include/qemu/memfd.h
> @@ -18,6 +18,7 @@
>  
>  int qemu_memfd_create(const char *name, size_t size, bool hugetlb,
>                        uint64_t hugetlbsize, unsigned int seals, Error **errp);
> +bool qemu_memfd_alloc_check(void);
>  void *qemu_memfd_alloc(const char *name, size_t size, unsigned int seals,
>                         int *fd, Error **errp);
>  void qemu_memfd_free(void *ptr, size_t size, int fd);
> diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
> index 250f886acb..27c1ec5fe8 100644
> --- a/hw/virtio/vhost.c
> +++ b/hw/virtio/vhost.c
> @@ -1223,7 +1223,7 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
>          if (!(hdev->features & (0x1ULL << VHOST_F_LOG_ALL))) {
>              error_setg(&hdev->migration_blocker,
>                         "Migration disabled: vhost lacks VHOST_F_LOG_ALL feature.");
> -        } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_check()) {
> +        } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_alloc_check()) {
>              error_setg(&hdev->migration_blocker,
>                         "Migration disabled: failed to allocate shared memory");
>          }
> diff --git a/util/memfd.c b/util/memfd.c
> index 07d579ea7d..277f7211af 100644
> --- a/util/memfd.c
> +++ b/util/memfd.c
> @@ -173,7 +173,13 @@ enum {
>      MEMFD_TODO
>  };
>  
> -bool qemu_memfd_check(void)
> +/**
> + * qemu_memfd_alloc_check():
> + *
> + * Check if qemu_memfd_alloc() can allocate, including using a
> + * fallback implementation when host doesn't support memfd.
> + */
> +bool qemu_memfd_alloc_check(void)
>  {
>      static int memfd_check = MEMFD_TODO;
>  
> @@ -188,3 +194,25 @@ bool qemu_memfd_check(void)
>  
>      return memfd_check == MEMFD_OK;
>  }
> +
> +/**
> + * qemu_memfd_check():
> + *
> + * Check if host supports memfd.
> + */
> +bool qemu_memfd_check(void)
> +{
> +    static int memfd_check = MEMFD_TODO;
> +
> +    if (memfd_check == MEMFD_TODO) {
> +        int mfd = memfd_create("test", 0);
> +        if (mfd >= 0) {
> +            memfd_check = MEMFD_OK;
> +            close(mfd);
> +        } else {
> +            memfd_check = MEMFD_KO;
> +        }
> +    }
> +
> +    return memfd_check == MEMFD_OK;
> +}
> -- 
> 2.17.0.rc1.1.g4c4f2b46a3
> 
>
Paolo Bonzini April 5, 2018, 3:26 p.m. UTC | #4 
On 28/03/2018 14:18, Marc-André Lureau wrote:
> On RHEL7, memfd is not supported, and vhost-user-test fails:
> TEST: tests/vhost-user-test... (pid=10248)
>   /x86_64/vhost-user/migrate:
>   qemu-system-x86_64: -object memory-backend-memfd,id=mem,size=2M,: failed to create memfd
> FAIL
> 
> There is a qemu_memfd_check() to prevent running memfd path, but it
> also checks for fallback implementation. Let's specialize
> qemu_memfd_check() to check memfd only, while qemu_memfd_alloc_check()
> checks for the qemu_memfd_alloc() API.
> 
> Reported-by: Miroslav Rezanina <mrezanin@redhat.com>
> Tested-by: Miroslav Rezanina <mrezanin@redhat.com>
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>  include/qemu/memfd.h |  1 +
>  hw/virtio/vhost.c    |  2 +-
>  util/memfd.c         | 30 +++++++++++++++++++++++++++++-
>  3 files changed, 31 insertions(+), 2 deletions(-)
> 
> diff --git a/include/qemu/memfd.h b/include/qemu/memfd.h
> index de10198ed6..49e79634da 100644
> --- a/include/qemu/memfd.h
> +++ b/include/qemu/memfd.h
> @@ -18,6 +18,7 @@
>  
>  int qemu_memfd_create(const char *name, size_t size, bool hugetlb,
>                        uint64_t hugetlbsize, unsigned int seals, Error **errp);
> +bool qemu_memfd_alloc_check(void);
>  void *qemu_memfd_alloc(const char *name, size_t size, unsigned int seals,
>                         int *fd, Error **errp);
>  void qemu_memfd_free(void *ptr, size_t size, int fd);
> diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
> index 250f886acb..27c1ec5fe8 100644
> --- a/hw/virtio/vhost.c
> +++ b/hw/virtio/vhost.c
> @@ -1223,7 +1223,7 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
>          if (!(hdev->features & (0x1ULL << VHOST_F_LOG_ALL))) {
>              error_setg(&hdev->migration_blocker,
>                         "Migration disabled: vhost lacks VHOST_F_LOG_ALL feature.");
> -        } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_check()) {
> +        } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_alloc_check()) {
>              error_setg(&hdev->migration_blocker,
>                         "Migration disabled: failed to allocate shared memory");
>          }
> diff --git a/util/memfd.c b/util/memfd.c
> index 07d579ea7d..277f7211af 100644
> --- a/util/memfd.c
> +++ b/util/memfd.c
> @@ -173,7 +173,13 @@ enum {
>      MEMFD_TODO
>  };
>  
> -bool qemu_memfd_check(void)
> +/**
> + * qemu_memfd_alloc_check():
> + *
> + * Check if qemu_memfd_alloc() can allocate, including using a
> + * fallback implementation when host doesn't support memfd.
> + */
> +bool qemu_memfd_alloc_check(void)
>  {
>      static int memfd_check = MEMFD_TODO;
>  
> @@ -188,3 +194,25 @@ bool qemu_memfd_check(void)
>  
>      return memfd_check == MEMFD_OK;
>  }
> +
> +/**
> + * qemu_memfd_check():
> + *
> + * Check if host supports memfd.
> + */
> +bool qemu_memfd_check(void)
> +{
> +    static int memfd_check = MEMFD_TODO;
> +
> +    if (memfd_check == MEMFD_TODO) {
> +        int mfd = memfd_create("test", 0);
> +        if (mfd >= 0) {
> +            memfd_check = MEMFD_OK;
> +            close(mfd);
> +        } else {
> +            memfd_check = MEMFD_KO;
> +        }
> +    }
> +
> +    return memfd_check == MEMFD_OK;
> +}
> 

Queued, thanks.

Paolo
diff mbox series

Patch

diff --git a/include/qemu/memfd.h b/include/qemu/memfd.h
index de10198ed6..49e79634da 100644
--- a/include/qemu/memfd.h
+++ b/include/qemu/memfd.h
@@ -18,6 +18,7 @@ 
 
 int qemu_memfd_create(const char *name, size_t size, bool hugetlb,
                       uint64_t hugetlbsize, unsigned int seals, Error **errp);
+bool qemu_memfd_alloc_check(void);
 void *qemu_memfd_alloc(const char *name, size_t size, unsigned int seals,
                        int *fd, Error **errp);
 void qemu_memfd_free(void *ptr, size_t size, int fd);
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index 250f886acb..27c1ec5fe8 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -1223,7 +1223,7 @@  int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
         if (!(hdev->features & (0x1ULL << VHOST_F_LOG_ALL))) {
             error_setg(&hdev->migration_blocker,
                        "Migration disabled: vhost lacks VHOST_F_LOG_ALL feature.");
-        } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_check()) {
+        } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_alloc_check()) {
             error_setg(&hdev->migration_blocker,
                        "Migration disabled: failed to allocate shared memory");
         }
diff --git a/util/memfd.c b/util/memfd.c
index 07d579ea7d..277f7211af 100644
--- a/util/memfd.c
+++ b/util/memfd.c
@@ -173,7 +173,13 @@  enum {
     MEMFD_TODO
 };
 
-bool qemu_memfd_check(void)
+/**
+ * qemu_memfd_alloc_check():
+ *
+ * Check if qemu_memfd_alloc() can allocate, including using a
+ * fallback implementation when host doesn't support memfd.
+ */
+bool qemu_memfd_alloc_check(void)
 {
     static int memfd_check = MEMFD_TODO;
 
@@ -188,3 +194,25 @@  bool qemu_memfd_check(void)
 
     return memfd_check == MEMFD_OK;
 }
+
+/**
+ * qemu_memfd_check():
+ *
+ * Check if host supports memfd.
+ */
+bool qemu_memfd_check(void)
+{
+    static int memfd_check = MEMFD_TODO;
+
+    if (memfd_check == MEMFD_TODO) {
+        int mfd = memfd_create("test", 0);
+        if (mfd >= 0) {
+            memfd_check = MEMFD_OK;
+            close(mfd);
+        } else {
+            memfd_check = MEMFD_KO;
+        }
+    }
+
+    return memfd_check == MEMFD_OK;
+}