Commit a345b23b authored by Joerg Roedel's avatar Joerg Roedel
Browse files

x86/amd-iommu: Reset command buffer on ILLEGAL_COMMAND_ERROR 



On an ILLEGAL_COMMAND_ERROR the IOMMU stops executing
further commands. This patch changes the code to handle this
case better by resetting the command buffer in the IOMMU.

Signed-off-by: default avatarJoerg Roedel <joerg.roedel@amd.com>
parent 93f1cc67

arch/x86/kernel/amd_iommu.c

+13 −2
Original line number Diff line number Diff line
@@ -61,6 +61,7 @@ static u64* alloc_pte(struct protection_domain *dom, 
static void dma_ops_reserve_addresses(struct dma_ops_domain *dom,

				      unsigned long start_page,

				      unsigned int pages);

static void reset_iommu_command_buffer(struct amd_iommu *iommu);



#ifndef BUS_NOTIFY_UNBOUND_DRIVER

#define BUS_NOTIFY_UNBOUND_DRIVER 0x0005
@@ -156,7 +157,7 @@ static void dump_command(unsigned long phys_addr) 
		pr_err("AMD-Vi: CMD[%d]: %08x\n", i, cmd->data[i]);

}



static void iommu_print_event(void *__evt)

static void iommu_print_event(struct amd_iommu *iommu, void *__evt)

{

	u32 *event = __evt;

	int type  = (event[1] >> EVENT_TYPE_SHIFT)  & EVENT_TYPE_MASK;
@@ -195,6 +196,7 @@ static void iommu_print_event(void *__evt) 
		break;

	case EVENT_TYPE_ILL_CMD:

		printk("ILLEGAL_COMMAND_ERROR address=0x%016llx]\n", address);

		reset_iommu_command_buffer(iommu);

		dump_command(address);

		break;

	case EVENT_TYPE_CMD_HARD_ERR:
@@ -229,7 +231,7 @@ static void iommu_poll_events(struct amd_iommu *iommu) 
	tail = readl(iommu->mmio_base + MMIO_EVT_TAIL_OFFSET);



	while (head != tail) {

		iommu_print_event(iommu->evt_buf + head);

		iommu_print_event(iommu, iommu->evt_buf + head);

		head = (head + EVENT_ENTRY_SIZE) % iommu->evt_buf_size;

	}
@@ -547,6 +549,15 @@ void amd_iommu_flush_all_devices(void) 
	}

}



static void reset_iommu_command_buffer(struct amd_iommu *iommu)

{

	pr_err("AMD-Vi: Resetting IOMMU command buffer\n");



	amd_iommu_reset_cmd_buffer(iommu);

	flush_all_devices_for_iommu(iommu);

	flush_all_domains_on_iommu(iommu);

}



/****************************************************************************

 *

 * The functions below are used the create the page table mappings for