> -----Original Message----- > From: Sitsofe Wheeler > Sent: Wednesday, August 27, 2014 20:16 PM > > > do_hypercall() fails due to HV_STATUS_INVALID_ALIGNMENT, if "the > > specified input or output GPA pointer is not aligned to 8 bytes", > > or, "the specified input or output parameter lists spans pages". > > Here the 'input' can rarely across the page boundary, especially when > > CONFIG_DEBUG_PAGEALLOC is on. > > It can also be returned when "The input or output GPA pointer is not within > the bounds of the GPA space." but I'm guessing that's not the case here? Hi Sitsofe, I think you're correct.
> > I'm making a patch for this. Please see the end of the mail for the inline patch and try it. (the patch hasn't been rebased against KY's patchset) > Thanks! Could these alignment problems have been the cause of all sorts > of intermittent errors like https://lkml.org/lkml/2014/7/11/870 (which > was caused by support being added for a bigger receive buffer)? Probably, let's try the patch first. :-) > > > I rebased your patch on top of the K.Y.'s "Drivers: hv: vmbus: Eliminate > > > calls to BUG_ON()" patch set (see below). The combination no longer > > > triggers the bug and it doesn't take too long to boot but the network > > > interface fails to work (which I believe is . > > the sentence is accidently trimmed here? :-) > > *Cough* That bit in brackets shouldn't be there. I've been unable to > link that stacktrace to an existing issue (I thought it might have been > https://lkml.org/lkml/2014/8/19/227 but that seems unlikely). I'm not 100% sure either. > > > > Boot dmesg output (there's no line that mentions retries). The > > > framebuffer window also didn't resize itself: > > > > > > [ 7.848030] hv_vmbus: registering driver hyperv_fb > > > [ 7.859759] hyperv_fb: Unable to open vmbus channel > > > [ 7.871812] hyperv_fb: Unable to connect to VSP > > We still see hyperv_fb can't work. > > How come things didn't work even though the retries message (which is > presumably printed if we exceed 10 attempts) was never printed? the "10 attempts" doesn't handle HV_STATUS_INVALID_ALIGNMENT. BTW, with the patch below, hyperv_fb can work now, BUT, *occasionally*, storvsc_probe() -> ... -> vmbus_open() -> can fail due to HV_STATUS_INVALID_ALIGNMENT... diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c index 531a593..f5283a0 100644 --- a/drivers/hv/channel.c +++ b/drivers/hv/channel.c @@ -165,8 +165,10 @@ int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size, ret = vmbus_post_msg(open_msg, sizeof(struct vmbus_channel_open_channel)); - if (ret != 0) + if (ret != 0) { + err = ret; goto error1; + } t = wait_for_completion_timeout(&open_info->waitevent, 5*HZ); if (t == 0) { diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c index edfc848..8366394 100644 --- a/drivers/hv/hv.c +++ b/drivers/hv/hv.c @@ -223,6 +223,9 @@ int hv_post_message(union hv_connection_id connection_id, }; struct hv_input_post_message *aligned_msg; + unsigned long alighed_msg_start, alighed_msg_end; + bool need_free_aligned_msg = false; + u16 status; unsigned long addr; @@ -233,9 +236,30 @@ int hv_post_message(union hv_connection_id connection_id, if (!addr) return -ENOMEM; + /* + * According to Hypervisor Top Level Functional Specification, + * do_hypercall() fails due to HV_STATUS_INVALID_ALIGNMENT, if "the + * specified input or output GPA pointer is not aligned to 8 bytes", + * or, "the specified input or output parameter lists spans pages". + */ aligned_msg = (struct hv_input_post_message *) (ALIGN(addr, HV_HYPERCALL_PARAM_ALIGN)); + alighed_msg_start = (unsigned long)aligned_msg; + alighed_msg_end = (unsigned long)&aligned_msg->payload + + payload_size - 1; + + if ((alighed_msg_start >> PAGE_SHIFT) != + (alighed_msg_end >> PAGE_SHIFT)) { + aligned_msg = (struct hv_input_post_message *) + __get_free_page(GFP_ATOMIC); + if (!aligned_msg) { + status = -ENOMEM; + goto out; + } + need_free_aligned_msg = true; + } + aligned_msg->connectionid = connection_id; aligned_msg->message_type = message_type; aligned_msg->payload_size = payload_size; @@ -244,6 +268,11 @@ int hv_post_message(union hv_connection_id connection_id, status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL) & 0xFFFF; + WARN(status == HV_STATUS_INVALID_ALIGNMENT, + "status = %d\n", status); + if (need_free_aligned_msg) + free_page((unsigned long)aligned_msg); +out: kfree((void *)addr); return status; _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
