Messages in this thread Patch in this message | | | Date | Tue, 31 May 2005 19:36:19 +0300 | From | "Michael S. Tsirkin" <> | Subject | [PATCH] pci-sysfs: backport fix for 2.6.11.12 |
| |
Greg, before 2.6.12, pci_write_config in pci-sysfs.c was broken, causing incorrect data being written to the configuration register, which in the case of my userspace driver results in system failure.
This has been fixed in 2.6.12-rc5:
http://www.kernel.org/diff/diffview.cgi?file=%2Fpub%2Flinux%2Fkernel%2Fv2.6%2Ftesting%2Fpatch-2.6.12-rc5.bz2;z=2656
Would you please consider merging the fix for 2.6.11.12 as well?
Alternatively (since there were multiple other changes in pci-sysfs.c), here's a small patch to fix just this issue.
Thanks, MST
cast from (signed) char to unsigned int in pci_write_config causes the result to be sign extended, clobbering high bits in the result. Thus:
# setpci -s 07:00.0 14.L=E4 # setpci -s 07:00.0 14.L ffffffe4
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
--- linux-2.6.11-openib/drivers/pci/pci-sysfs.c.bad 2005-05-30 13:45:02.000000000 +0300 +++ linux-2.6.11-openib/drivers/pci/pci-sysfs.c 2005-05-30 13:51:39.000000000 +0300 @@ -161,10 +161,10 @@ pci_write_config(struct kobject *kobj, c } while (size > 3) { - unsigned int val = buf[off - init_off]; - val |= (unsigned int) buf[off - init_off + 1] << 8; - val |= (unsigned int) buf[off - init_off + 2] << 16; - val |= (unsigned int) buf[off - init_off + 3] << 24; + unsigned int val = (u8)buf[off - init_off]; + val |= (unsigned int)(u8)buf[off - init_off + 1] << 8; + val |= (unsigned int)(u8)buf[off - init_off + 2] << 16; + val |= (unsigned int)(u8)buf[off - init_off + 3] << 24; pci_write_config_dword(dev, off, val); off += 4; size -= 4; -- MST - Michael S. Tsirkin - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |