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