diff options
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/boot/vmem.c | 3 | ||||
| -rw-r--r-- | arch/s390/hypfs/hypfs_dbfs.c | 19 |
2 files changed, 15 insertions, 7 deletions
diff --git a/arch/s390/boot/vmem.c b/arch/s390/boot/vmem.c index 3fa28db2fe59..14aee8524021 100644 --- a/arch/s390/boot/vmem.c +++ b/arch/s390/boot/vmem.c @@ -471,6 +471,9 @@ void setup_vmem(unsigned long kernel_start, unsigned long kernel_end, unsigned l lowcore_address + sizeof(struct lowcore), POPULATE_LOWCORE); for_each_physmem_usable_range(i, &start, &end) { + /* Do not map lowcore with identity mapping */ + if (!start) + start = sizeof(struct lowcore); pgtable_populate((unsigned long)__identity_va(start), (unsigned long)__identity_va(end), POPULATE_IDENTITY); diff --git a/arch/s390/hypfs/hypfs_dbfs.c b/arch/s390/hypfs/hypfs_dbfs.c index 5d9effb0867c..41a0d2066fa0 100644 --- a/arch/s390/hypfs/hypfs_dbfs.c +++ b/arch/s390/hypfs/hypfs_dbfs.c @@ -6,6 +6,7 @@ * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com> */ +#include <linux/security.h> #include <linux/slab.h> #include "hypfs.h" @@ -66,23 +67,27 @@ static long dbfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) long rc; mutex_lock(&df->lock); - if (df->unlocked_ioctl) - rc = df->unlocked_ioctl(file, cmd, arg); - else - rc = -ENOTTY; + rc = df->unlocked_ioctl(file, cmd, arg); mutex_unlock(&df->lock); return rc; } -static const struct file_operations dbfs_ops = { +static const struct file_operations dbfs_ops_ioctl = { .read = dbfs_read, .unlocked_ioctl = dbfs_ioctl, }; +static const struct file_operations dbfs_ops = { + .read = dbfs_read, +}; + void hypfs_dbfs_create_file(struct hypfs_dbfs_file *df) { - df->dentry = debugfs_create_file(df->name, 0400, dbfs_dir, df, - &dbfs_ops); + const struct file_operations *fops = &dbfs_ops; + + if (df->unlocked_ioctl && !security_locked_down(LOCKDOWN_DEBUGFS)) + fops = &dbfs_ops_ioctl; + df->dentry = debugfs_create_file(df->name, 0400, dbfs_dir, df, fops); mutex_init(&df->lock); } |