s390/pci: add exception table to load/store instructions
Don't let pci_load and friends crash the kernel when called with
e.g. an invalid offset. Return -ENXIO instead.
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/pci_io.h b/arch/s390/include/asm/pci_io.h
index a312c7e..0e0bec9 100644
--- a/arch/s390/include/asm/pci_io.h
+++ b/arch/s390/include/asm/pci_io.h
@@ -89,7 +89,7 @@
static inline int zpci_read_single(u64 req, u64 *dst, u64 offset, u8 len)
{
u64 data;
- u8 cc;
+ int cc;
cc = s390pci_load(&data, req, offset);
switch (len) {
diff --git a/arch/s390/pci/pci_insn.c b/arch/s390/pci/pci_insn.c
index d9b573b..4bc32f3 100644
--- a/arch/s390/pci/pci_insn.c
+++ b/arch/s390/pci/pci_insn.c
@@ -8,6 +8,7 @@
#include <linux/errno.h>
#include <linux/delay.h>
#include <asm/pci_insn.h>
+#include <asm/processor.h>
#define ZPCI_INSN_BUSY_DELAY 1 /* 1 microsecond */
@@ -85,18 +86,20 @@
}
/* PCI Load */
-static inline u8 __pcilg(u64 *data, u64 req, u64 offset, u8 *status)
+static inline int __pcilg(u64 *data, u64 req, u64 offset, u8 *status)
{
register u64 __req asm("2") = req;
register u64 __offset asm("3") = offset;
+ int cc = -ENXIO;
u64 __data;
- u8 cc;
asm volatile (
" .insn rre,0xb9d20000,%[data],%[req]\n"
- " ipm %[cc]\n"
+ "0: ipm %[cc]\n"
" srl %[cc],28\n"
- : [cc] "=d" (cc), [data] "=d" (__data), [req] "+d" (__req)
+ "1:\n"
+ EX_TABLE(0b, 1b)
+ : [cc] "+d" (cc), [data] "=d" (__data), [req] "+d" (__req)
: "d" (__offset)
: "cc");
*status = __req >> 24 & 0xff;
@@ -106,7 +109,8 @@
int s390pci_load(u64 *data, u64 req, u64 offset)
{
- u8 cc, status;
+ u8 status;
+ int cc;
do {
cc = __pcilg(data, req, offset, &status);
@@ -114,29 +118,27 @@
udelay(ZPCI_INSN_BUSY_DELAY);
} while (cc == 2);
- if (cc) {
+ if (cc)
printk_once(KERN_ERR "%s: error cc: %d status: %d req: %Lx offset: %Lx\n",
__func__, cc, status, req, offset);
- /* TODO: on IO errors set data to 0xff...
- * here or in users of pcilg (le conversion)?
- */
- }
- return (cc) ? -EIO : 0;
+ return (cc > 0) ? -EIO : cc;
}
EXPORT_SYMBOL_GPL(s390pci_load);
/* PCI Store */
-static inline u8 __pcistg(u64 data, u64 req, u64 offset, u8 *status)
+static inline int __pcistg(u64 data, u64 req, u64 offset, u8 *status)
{
register u64 __req asm("2") = req;
register u64 __offset asm("3") = offset;
- u8 cc;
+ int cc = -ENXIO;
asm volatile (
" .insn rre,0xb9d00000,%[data],%[req]\n"
- " ipm %[cc]\n"
+ "0: ipm %[cc]\n"
" srl %[cc],28\n"
- : [cc] "=d" (cc), [req] "+d" (__req)
+ "1:\n"
+ EX_TABLE(0b, 1b)
+ : [cc] "+d" (cc), [req] "+d" (__req)
: "d" (__offset), [data] "d" (data)
: "cc");
*status = __req >> 24 & 0xff;
@@ -145,7 +147,8 @@
int s390pci_store(u64 data, u64 req, u64 offset)
{
- u8 cc, status;
+ u8 status;
+ int cc;
do {
cc = __pcistg(data, req, offset, &status);
@@ -156,20 +159,22 @@
if (cc)
printk_once(KERN_ERR "%s: error cc: %d status: %d req: %Lx offset: %Lx\n",
__func__, cc, status, req, offset);
- return (cc) ? -EIO : 0;
+ return (cc > 0) ? -EIO : cc;
}
EXPORT_SYMBOL_GPL(s390pci_store);
/* PCI Store Block */
-static inline u8 __pcistb(const u64 *data, u64 req, u64 offset, u8 *status)
+static inline int __pcistb(const u64 *data, u64 req, u64 offset, u8 *status)
{
- u8 cc;
+ int cc = -ENXIO;
asm volatile (
" .insn rsy,0xeb00000000d0,%[req],%[offset],%[data]\n"
- " ipm %[cc]\n"
+ "0: ipm %[cc]\n"
" srl %[cc],28\n"
- : [cc] "=d" (cc), [req] "+d" (req)
+ "1:\n"
+ EX_TABLE(0b, 1b)
+ : [cc] "+d" (cc), [req] "+d" (req)
: [offset] "d" (offset), [data] "Q" (*data)
: "cc");
*status = req >> 24 & 0xff;
@@ -178,7 +183,8 @@
int s390pci_store_block(const u64 *data, u64 req, u64 offset)
{
- u8 cc, status;
+ u8 status;
+ int cc;
do {
cc = __pcistb(data, req, offset, &status);
@@ -189,6 +195,6 @@
if (cc)
printk_once(KERN_ERR "%s: error cc: %d status: %d req: %Lx offset: %Lx\n",
__func__, cc, status, req, offset);
- return (cc) ? -EIO : 0;
+ return (cc > 0) ? -EIO : cc;
}
EXPORT_SYMBOL_GPL(s390pci_store_block);
