xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

kvm: x86, powerpc: do not allow clearing largepages debugfs entry

Browse Source 
The largepages debugfs entry is incremented/decremented as shadow
pages are created or destroyed.  Clearing it will result in an
underflow, which is harmless to KVM but ugly (and could be
misinterpreted by tools that use debugfs information), so make
this particular statistic read-only.

Cc: kvm-ppc@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini
2019-09-30 18:48:44 +02:00
parent 2e4a75976d
commit 833b45de69
4 changed files with 16 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
virt/kvm/kvm_main.c
View File

@@ -617,8 +617,9 @@ static int kvm_create_vm_debugfs(struct kvm *kvm, int fd)
stat_data->kvm = kvm;
stat_data->offset = p->offset;
stat_data->mode = p->mode ? p->mode : 0644;
kvm->debugfs_stat_data[p - debugfs_entries] = stat_data;
debugfs_create_file(p->name, 0644, kvm->debugfs_dentry,
debugfs_create_file(p->name, stat_data->mode, kvm->debugfs_dentry,
stat_data, stat_fops_per_vm[p->kind]);
}
return 0;
@@ -3929,7 +3930,9 @@ static int kvm_debugfs_open(struct inode *inode, struct file *file,
if (!refcount_inc_not_zero(&stat_data->kvm->users_count))
return -ENOENT;
if (simple_attr_open(inode, file, get, set, fmt)) {
if (simple_attr_open(inode, file, get,
stat_data->mode & S_IWUGO ? set : NULL,
fmt)) {
kvm_put_kvm(stat_data->kvm);
return -ENOMEM;
}
@@ -4177,7 +4180,8 @@ static void kvm_init_debug(void)
kvm_debugfs_num_entries = 0;
for (p = debugfs_entries; p->name; ++p, kvm_debugfs_num_entries++) {
debugfs_create_file(p->name, 0644, kvm_debugfs_dir,
int mode = p->mode ? p->mode : 0644;
debugfs_create_file(p->name, mode, kvm_debugfs_dir,
(void *)(long)p->offset,
stat_fops[p->kind]);
}