aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/ia64/aliasing-test.c
diff options
context:
space:
mode:
authorAlex Chiang <achiang@hp.com>2007-07-11 11:02:15 -0600
committerTony Luck <tony.luck@intel.com>2007-07-11 11:34:49 -0700
commit012b7105cc816fb797eb1c161cdfc0052b5c3f53 (patch)
tree084ede189a3284c17f09ea68d0d4573d95e7499f /Documentation/ia64/aliasing-test.c
parent9e121327b37b751ef66e6f57e2d02dd568955148 (diff)
[IA64] prevent MCA when performing MMIO mmap to PCI config space
Example memory map (HP rx7640 with 'default' acpiconfig setting, VGA disabled): 0x00000000 - 0x3FFFBFFF supports only WB (cacheable) access If a user attempts to perform an MMIO mmap (using the PCIIOC_MMAP_IS_MEM ioctl) to PCI config space (like mmap'ing and accessing memory at 0xA0000), we will MCA because the kernel will attempt to use a mapping with the UC attribute. So check the memory attribute in kern_mmap and the EFI memmap. If WC is requested, and WC or UC access is supported for the region, allow it. Otherwise, use the same attribute the kernel uses. Updates documentation and test cases as well. Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
Diffstat (limited to 'Documentation/ia64/aliasing-test.c')
-rw-r--r--Documentation/ia64/aliasing-test.c26
1 files changed, 19 insertions, 7 deletions
diff --git a/Documentation/ia64/aliasing-test.c b/Documentation/ia64/aliasing-test.c
index d485256ee1ce..773a814d4093 100644
--- a/Documentation/ia64/aliasing-test.c
+++ b/Documentation/ia64/aliasing-test.c
@@ -19,6 +19,7 @@
#include <sys/mman.h>
#include <sys/stat.h>
#include <unistd.h>
+#include <linux/pci.h>
int sum;
@@ -34,13 +35,19 @@ int map_mem(char *path, off_t offset, size_t length, int touch)
return -1;
}
+ if (fnmatch("/proc/bus/pci/*", path, 0) == 0) {
+ rc = ioctl(fd, PCIIOC_MMAP_IS_MEM);
+ if (rc == -1)
+ perror("PCIIOC_MMAP_IS_MEM ioctl");
+ }
+
addr = mmap(NULL, length, PROT_READ|PROT_WRITE, MAP_SHARED, fd, offset);
if (addr == MAP_FAILED)
return 1;
if (touch) {
c = (int *) addr;
- while (c < (int *) (offset + length))
+ while (c < (int *) (addr + length))
sum += *c++;
}
@@ -54,7 +61,7 @@ int map_mem(char *path, off_t offset, size_t length, int touch)
return 0;
}
-int scan_sysfs(char *path, char *file, off_t offset, size_t length, int touch)
+int scan_tree(char *path, char *file, off_t offset, size_t length, int touch)
{
struct dirent **namelist;
char *name, *path2;
@@ -93,7 +100,7 @@ int scan_sysfs(char *path, char *file, off_t offset, size_t length, int touch)
} else {
r = lstat(path2, &buf);
if (r == 0 && S_ISDIR(buf.st_mode)) {
- rc = scan_sysfs(path2, file, offset, length, touch);
+ rc = scan_tree(path2, file, offset, length, touch);
if (rc < 0)
return rc;
}
@@ -238,10 +245,15 @@ int main()
else
fprintf(stderr, "FAIL: /dev/mem 0x0-0x100000 not accessible\n");
- scan_sysfs("/sys/class/pci_bus", "legacy_mem", 0, 0xA0000, 1);
- scan_sysfs("/sys/class/pci_bus", "legacy_mem", 0xA0000, 0x20000, 0);
- scan_sysfs("/sys/class/pci_bus", "legacy_mem", 0xC0000, 0x40000, 1);
- scan_sysfs("/sys/class/pci_bus", "legacy_mem", 0, 1024*1024, 0);
+ scan_tree("/sys/class/pci_bus", "legacy_mem", 0, 0xA0000, 1);
+ scan_tree("/sys/class/pci_bus", "legacy_mem", 0xA0000, 0x20000, 0);
+ scan_tree("/sys/class/pci_bus", "legacy_mem", 0xC0000, 0x40000, 1);
+ scan_tree("/sys/class/pci_bus", "legacy_mem", 0, 1024*1024, 0);
scan_rom("/sys/devices", "rom");
+
+ scan_tree("/proc/bus/pci", "??.?", 0, 0xA0000, 1);
+ scan_tree("/proc/bus/pci", "??.?", 0xA0000, 0x20000, 0);
+ scan_tree("/proc/bus/pci", "??.?", 0xC0000, 0x40000, 1);
+ scan_tree("/proc/bus/pci", "??.?", 0, 1024*1024, 0);
}

Privacy Policy