184 lines
6.0 KiB
Diff
184 lines
6.0 KiB
Diff
|
From 1b9f228788eb2d7f50961241e28f7a9afadc62ab Mon Sep 17 00:00:00 2001
|
||
|
From: Stefan Hajnoczi <stefanha@redhat.com>
|
||
|
Date: Thu, 21 Mar 2019 10:56:08 +0000
|
||
|
Subject: [PATCH 7/9] hostmem-file: reject invalid pmem file sizes
|
||
|
|
||
|
RH-Author: Stefan Hajnoczi <stefanha@redhat.com>
|
||
|
Message-id: <20190321105608.29960-2-stefanha@redhat.com>
|
||
|
Patchwork-id: 85081
|
||
|
O-Subject: [RHEL-AV-8.0.1 qemu-kvm PATCH 1/1] hostmem-file: reject invalid pmem file sizes
|
||
|
Bugzilla: 1669053
|
||
|
RH-Acked-by: Eduardo Habkost <ehabkost@redhat.com>
|
||
|
RH-Acked-by: Pankaj Gupta <pagupta@redhat.com>
|
||
|
RH-Acked-by: Igor Mammedov <imammedo@redhat.com>
|
||
|
|
||
|
Guests started with NVDIMMs larger than the underlying host file produce
|
||
|
confusing errors inside the guest. This happens because the guest
|
||
|
accesses pages beyond the end of the file.
|
||
|
|
||
|
Check the pmem file size on startup and print a clear error message if
|
||
|
the size is invalid.
|
||
|
|
||
|
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1669053
|
||
|
Cc: Wei Yang <richardw.yang@linux.intel.com>
|
||
|
Cc: Zhang Yi <yi.z.zhang@linux.intel.com>
|
||
|
Cc: Eduardo Habkost <ehabkost@redhat.com>
|
||
|
Cc: Igor Mammedov <imammedo@redhat.com>
|
||
|
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
|
||
|
Message-Id: <20190214031004.32522-3-stefanha@redhat.com>
|
||
|
Reviewed-by: Wei Yang <richardw.yang@linux.intel.com>
|
||
|
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
|
||
|
Reviewed-by: Pankaj Gupta <pagupta@redhat.com>
|
||
|
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
|
||
|
(cherry picked from commit 314aec4a6e06844937f1677f6cba21981005f389)
|
||
|
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
|
||
|
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
|
||
|
---
|
||
|
backends/hostmem-file.c | 23 +++++++++++++++++++++
|
||
|
include/qemu/osdep.h | 13 ++++++++++++
|
||
|
util/oslib-posix.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++
|
||
|
util/oslib-win32.c | 5 +++++
|
||
|
4 files changed, 94 insertions(+)
|
||
|
|
||
|
diff --git a/backends/hostmem-file.c b/backends/hostmem-file.c
|
||
|
index 6630021..8d85d56 100644
|
||
|
--- a/backends/hostmem-file.c
|
||
|
+++ b/backends/hostmem-file.c
|
||
|
@@ -57,6 +57,29 @@ file_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
|
||
|
#ifndef CONFIG_POSIX
|
||
|
error_setg(errp, "-mem-path not supported on this host");
|
||
|
#else
|
||
|
+
|
||
|
+ /*
|
||
|
+ * Verify pmem file size since starting a guest with an incorrect size
|
||
|
+ * leads to confusing failures inside the guest.
|
||
|
+ */
|
||
|
+ if (fb->is_pmem) {
|
||
|
+ Error *local_err = NULL;
|
||
|
+ uint64_t size;
|
||
|
+
|
||
|
+ size = qemu_get_pmem_size(fb->mem_path, &local_err);
|
||
|
+ if (!size) {
|
||
|
+ error_propagate(errp, local_err);
|
||
|
+ return;
|
||
|
+ }
|
||
|
+
|
||
|
+ if (backend->size > size) {
|
||
|
+ error_setg(errp, "size property %" PRIu64 " is larger than "
|
||
|
+ "pmem file \"%s\" size %" PRIu64, backend->size,
|
||
|
+ fb->mem_path, size);
|
||
|
+ return;
|
||
|
+ }
|
||
|
+ }
|
||
|
+
|
||
|
backend->force_prealloc = mem_prealloc;
|
||
|
path = object_get_canonical_path(OBJECT(backend));
|
||
|
memory_region_init_ram_from_file(&backend->mr, OBJECT(backend),
|
||
|
diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h
|
||
|
index 3bf48bc..c68a85b 100644
|
||
|
--- a/include/qemu/osdep.h
|
||
|
+++ b/include/qemu/osdep.h
|
||
|
@@ -553,6 +553,19 @@ void os_mem_prealloc(int fd, char *area, size_t sz, int smp_cpus,
|
||
|
Error **errp);
|
||
|
|
||
|
/**
|
||
|
+ * qemu_get_pmem_size:
|
||
|
+ * @filename: path to a pmem file
|
||
|
+ * @errp: pointer to a NULL-initialized error object
|
||
|
+ *
|
||
|
+ * Determine the size of a persistent memory file. Besides supporting files on
|
||
|
+ * DAX file systems, this function also supports Linux devdax character
|
||
|
+ * devices.
|
||
|
+ *
|
||
|
+ * Returns: the size or 0 on failure
|
||
|
+ */
|
||
|
+uint64_t qemu_get_pmem_size(const char *filename, Error **errp);
|
||
|
+
|
||
|
+/**
|
||
|
* qemu_get_pid_name:
|
||
|
* @pid: pid of a process
|
||
|
*
|
||
|
diff --git a/util/oslib-posix.c b/util/oslib-posix.c
|
||
|
index 97b2f3b..b173fc0 100644
|
||
|
--- a/util/oslib-posix.c
|
||
|
+++ b/util/oslib-posix.c
|
||
|
@@ -496,6 +496,59 @@ void os_mem_prealloc(int fd, char *area, size_t memory, int smp_cpus,
|
||
|
}
|
||
|
}
|
||
|
|
||
|
+uint64_t qemu_get_pmem_size(const char *filename, Error **errp)
|
||
|
+{
|
||
|
+ struct stat st;
|
||
|
+
|
||
|
+ if (stat(filename, &st) < 0) {
|
||
|
+ error_setg(errp, "unable to stat pmem file \"%s\"", filename);
|
||
|
+ return 0;
|
||
|
+ }
|
||
|
+
|
||
|
+#if defined(__linux__)
|
||
|
+ /* Special handling for devdax character devices */
|
||
|
+ if (S_ISCHR(st.st_mode)) {
|
||
|
+ char *subsystem_path = NULL;
|
||
|
+ char *subsystem = NULL;
|
||
|
+ char *size_path = NULL;
|
||
|
+ char *size_str = NULL;
|
||
|
+ uint64_t ret = 0;
|
||
|
+
|
||
|
+ subsystem_path = g_strdup_printf("/sys/dev/char/%d:%d/subsystem",
|
||
|
+ major(st.st_rdev), minor(st.st_rdev));
|
||
|
+ subsystem = g_file_read_link(subsystem_path, NULL);
|
||
|
+ if (!subsystem) {
|
||
|
+ error_setg(errp, "unable to read subsystem for pmem file \"%s\"",
|
||
|
+ filename);
|
||
|
+ goto devdax_err;
|
||
|
+ }
|
||
|
+
|
||
|
+ if (!g_str_has_suffix(subsystem, "/dax")) {
|
||
|
+ error_setg(errp, "pmem file \"%s\" is not a dax device", filename);
|
||
|
+ goto devdax_err;
|
||
|
+ }
|
||
|
+
|
||
|
+ size_path = g_strdup_printf("/sys/dev/char/%d:%d/size",
|
||
|
+ major(st.st_rdev), minor(st.st_rdev));
|
||
|
+ if (!g_file_get_contents(size_path, &size_str, NULL, NULL)) {
|
||
|
+ error_setg(errp, "unable to read size for pmem file \"%s\"",
|
||
|
+ size_path);
|
||
|
+ goto devdax_err;
|
||
|
+ }
|
||
|
+
|
||
|
+ ret = g_ascii_strtoull(size_str, NULL, 0);
|
||
|
+
|
||
|
+devdax_err:
|
||
|
+ g_free(size_str);
|
||
|
+ g_free(size_path);
|
||
|
+ g_free(subsystem);
|
||
|
+ g_free(subsystem_path);
|
||
|
+ return ret;
|
||
|
+ }
|
||
|
+#endif /* defined(__linux__) */
|
||
|
+
|
||
|
+ return st.st_size;
|
||
|
+}
|
||
|
|
||
|
char *qemu_get_pid_name(pid_t pid)
|
||
|
{
|
||
|
diff --git a/util/oslib-win32.c b/util/oslib-win32.c
|
||
|
index b4c17f5..bd633af 100644
|
||
|
--- a/util/oslib-win32.c
|
||
|
+++ b/util/oslib-win32.c
|
||
|
@@ -560,6 +560,11 @@ void os_mem_prealloc(int fd, char *area, size_t memory, int smp_cpus,
|
||
|
}
|
||
|
}
|
||
|
|
||
|
+uint64_t qemu_get_pmem_size(const char *filename, Error **errp)
|
||
|
+{
|
||
|
+ error_setg(errp, "pmem support not available");
|
||
|
+ return 0;
|
||
|
+}
|
||
|
|
||
|
char *qemu_get_pid_name(pid_t pid)
|
||
|
{
|
||
|
--
|
||
|
1.8.3.1
|
||
|
|