Gitweb:
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=ee71c2f9ee85117e41ef87357ed8f75d29369b98
Commit: ee71c2f9ee85117e41ef87357ed8f75d29369b98
Parent: df8ec2490fed5dd23316bbb2c2e90e59e7d37126
Author: Stefan Richter <[EMAIL PROTECTED]>
AuthorDate: Sat Aug 25 14:08:19 2007 +0200
Committer: Stefan Richter <[EMAIL PROTECTED]>
CommitDate: Wed Oct 17 00:00:05 2007 +0200
firewire: fw-ohci: enforce read order for selfID generation
It seems unlikely, but access to self_id_cpu[0] could at least in theory
be deferred until after the loop over self_id_cpu[1..n] or even after
the subsequent reg_read. Enforce the desired order by a read barrier.
Also prevent the reg_read from being reordered relative to the for loop.
This isn't necessary if the loop's conditional printk counts as an
implicit barrier, but better make it explicit.
(self_id_cpu[] is a coherent DMA buffer.)
Signed-off-by: Stefan Richter <[EMAIL PROTECTED]>
---
drivers/firewire/fw-ohci.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)
diff --git a/drivers/firewire/fw-ohci.c b/drivers/firewire/fw-ohci.c
index e14c1ca..a7947ba 100644
--- a/drivers/firewire/fw-ohci.c
+++ b/drivers/firewire/fw-ohci.c
@@ -30,6 +30,7 @@
#include <asm/uaccess.h>
#include <asm/semaphore.h>
+#include <asm/system.h>
#include "fw-transaction.h"
#include "fw-ohci.h"
@@ -926,12 +927,14 @@ static void bus_reset_tasklet(unsigned long data)
self_id_count = (reg_read(ohci, OHCI1394_SelfIDCount) >> 3) & 0x3ff;
generation = (le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
+ rmb();
for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
if (ohci->self_id_cpu[i] != ~ohci->self_id_cpu[i + 1])
fw_error("inconsistent self IDs\n");
ohci->self_id_buffer[j] = le32_to_cpu(ohci->self_id_cpu[i]);
}
+ rmb();
/*
* Check the consistency of the self IDs we just read. The
-
To unsubscribe from this list: send the line "unsubscribe git-commits-head" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
