[PATCH v2 02/12] fs/proc/vmcore: replace vmcoredd_mutex by vmcore_mutex

David Hildenbrand
2024-12-04T12:55:00Z

Now that we have a mutex that synchronizes against opening of the vmcore,
let's use that one to replace vmcoredd_mutex: there is no need to have
two separate ones.

This is a preparation for properly preventing vmcore modifications
after the vmcore was opened.

Signed-off-by: David Hildenbrand <david@redhat.com>
---
fs/proc/vmcore.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c
index 586f84677d2f..e5a7e302f91f 100644
--- a/fs/proc/vmcore.c
+++ b/fs/proc/vmcore.c
@@ -53,7 +53,6 @@ static struct proc_dir_entry *proc_vmcore;
#ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP
/* Device Dump list and mutex to synchronize access to list */
static LIST_HEAD(vmcoredd_list);
-static DEFINE_MUTEX(vmcoredd_mutex);

static bool vmcoredd_disabled;
core_param(novmcoredd, vmcoredd_disabled, bool, 0);
@@ -248,7 +247,7 @@ static int vmcoredd_copy_dumps(struct iov_iter *iter, u64 start, size_t size)
size_t tsz;
char *buf;

- mutex_lock(&vmcoredd_mutex);
+ mutex_lock(&vmcore_mutex);
list_for_each_entry(dump, &vmcoredd_list, list) {
if (start < offset + dump->size) {
tsz = min(offset + (u64)dump->size - start, (u64)size);
@@ -269,7 +268,7 @@ static int vmcoredd_copy_dumps(struct iov_iter *iter, u64 start, size_t size)
}

out_unlock:
- mutex_unlock(&vmcoredd_mutex);
+ mutex_unlock(&vmcore_mutex);
return ret;
}

@@ -283,7 +282,7 @@ static int vmcoredd_mmap_dumps(struct vm_area_struct *vma, unsigned long dst,
size_t tsz;
char *buf;

- mutex_lock(&vmcoredd_mutex);
+ mutex_lock(&vmcore_mutex);
list_for_each_entry(dump, &vmcoredd_list, list) {
if (start < offset + dump->size) {
tsz = min(offset + (u64)dump->size - start, (u64)size);
@@ -306,7 +305,7 @@ static int vmcoredd_mmap_dumps(struct vm_area_struct *vma, unsigned long dst,
}

out_unlock:
- mutex_unlock(&vmcoredd_mutex);
+ mutex_unlock(&vmcore_mutex);
return ret;
}
#endif /* CONFIG_MMU */
@@ -1518,9 +1517,9 @@ int vmcore_add_device_dump(struct vmcoredd_data *data)
dump->size = data_size;

/* Add the dump to driver sysfs list */
- mutex_lock(&vmcoredd_mutex);
+ mutex_lock(&vmcore_mutex);
list_add_tail(&dump->list, &vmcoredd_list);
- mutex_unlock(&vmcoredd_mutex);
+ mutex_unlock(&vmcore_mutex);

vmcoredd_update_size(data_size);
return 0;
@@ -1538,7 +1537,7 @@ EXPORT_SYMBOL(vmcore_add_device_dump);
static void vmcore_free_device_dumps(void)
{
#ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP
- mutex_lock(&vmcoredd_mutex);
+ mutex_lock(&vmcore_mutex);
while (!list_empty(&vmcoredd_list)) {
struct vmcoredd_node *dump;

@@ -1548,7 +1547,7 @@ static void vmcore_free_device_dumps(void)
vfree(dump->buf);
vfree(dump);
}
- mutex_unlock(&vmcoredd_mutex);
+ mutex_unlock(&vmcore_mutex);
#endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */
}

--
2.47.1