Re: [PATCH 2/2 V5] iommu/amd: Add logic to decode AMD IOMMU event flag

From: Shuah Khan
Date: Wed Apr 10 2013 - 12:21:36 EST

On Wed, Apr 10, 2013 at 9:57 AM, <suravee.suthikulpanit@xxxxxxx> wrote:
> From: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
>
> Add logic to decode AMD IOMMU event flag based on information from AMD IOMMU specification.
> This should simplify debugging IOMMU errors. Also, dump DTE information in some additional
> cases.
>
> Example (default): The flags is now decoded.
> AMD-Vi: Event logged [INVALID_DEVICE_REQUEST device=51:00.0 address=0x0000000000000000 flags:G Nx Usr I P W N-Pm Rsv Tl type(0x7)]
> AMD-Vi: DTE[0..3]: 600000dfa760b403 0000000000000014 200000dfaba60c11 0000000000000000
>
> Example (amd-iommu=verbose): The flags and error types are decoded
> AMD-Vi: Event logged [INVALID_DEVICE_REQUEST device=51:00.0 address=0x0000000000000000 flags:G Nx Usr I P W N-Pm Rsv Tl]
> AMD-Vi: Error type details: (0x7) Invalid transaction to the system management address range
> AMD-Vi: DTE[0..3]: 600000dfa760b403 0000000000000014 200000dfaba60c11 0000000000000000
>
> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
> V5:
> * Keeping flag decode in 1 line (as requested by Joerg)
> * Use "amd-iommu=verbose" for additional printing
> V4:
> * Change print out format to reduce noise
> * Remove "(Note:...)"
> V3:
> * Move comments to end of line
> * Shorten the print out to be within one line
> V2:
> * Fix printing format to reduce noise
> * Use string table instead of switch/case
> * Use pr_cont instead of printk
>
> ---
> drivers/iommu/amd_iommu.c | 215 +++++++++++++++++++++++++++++++++++----------
> 1 file changed, 168 insertions(+), 47 deletions(-)
>
> diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
> index b287ca3..beb61dd 100644
> --- a/drivers/iommu/amd_iommu.c
> +++ b/drivers/iommu/amd_iommu.c
> @@ -601,13 +601,118 @@ static void amd_iommu_stats_init(void)
> *
> ****************************************************************************/
>
> +struct _event_log_flags {
> + u32 gn:1, /* 16 */
> + nx:1, /* 17 */
> + us:1, /* 18 */
> + i:1, /* 19 */
> + pr:1, /* 20 */
> + rw:1, /* 21 */
> + pe:1, /* 22 */
> + rz:1, /* 23 */
> + tr:1, /* 24 */
> + type:3, /* [27:25] */
> + _reserved_:20; /* Reserved */
> +};
> +
> +static const char * const _type_field_encodings[] = {
> + "Reserved", /* 00 */
> + "Master Abort", /* 01 */
> + "Target Abort", /* 10 */
> + "Data Error", /* 11 */
> +};
> +
> +static const char * const _invalid_trnsac_desc[] = {
> + "Read request or non-posted write in the interrupt "
> + "addres range", /* 000 */
> + "Pretranslated transaction received from an "
> + "I/O device that has I=0 or V=0 in DTE", /* 001 */
> + "Port I/O space transaction received from an "
> + "I/O device that has IoCtl=00b in DTE", /* 010 */
> + "Posted write to invalid address range", /* 011 */
> + "Invalid read request or non-posted write", /* 100 */
> + "Posted write to the interrupt/EOI range from an "
> + "I/O device that has IntCtl=00b in DTE", /* 101 */
> + "Posted write to a reserved interrupt address range", /* 110 */
> + "Invalid transaction to the system management "
> + "address range", /* 111 */
> +};
> +
> +static const char * const _invalid_trnslt_desc[] = {
> + "Translation request received from an I/O device "
> + "that has I=0, or has V=0, or has V=1 and "
> + "TV=0 in DTE", /* 000 */
> + "Translation request in invalid address range", /* 001 */
> + "Invalid translation request", /* 010 */
> + "Reserved", /* 011 */
> + "Reserved", /* 100 */
> + "Reserved", /* 101 */
> + "Reserved", /* 110 */
> + "Reserved", /* 111 */
> +};
> +
> +static void dump_detail_error(struct _event_log_flags *p, int ev_type)
> +{
> + u32 err_type = p->type;
> +
> + pr_err("AMD-Vi: Error type details: (0x%x) ", err_type);
> + if ((ev_type == EVENT_TYPE_DEV_TAB_ERR) ||
> + (ev_type == EVENT_TYPE_PAGE_TAB_ERR) ||
> + (ev_type == EVENT_TYPE_CMD_HARD_ERR)) {
> + if (err_type < ARRAY_SIZE(_type_field_encodings)) {
> + pr_cont("%s\n",
> + _type_field_encodings[err_type]);
> + }
> + } else if (ev_type == EVENT_TYPE_INV_DEV_REQ) {
> + if (p->tr == 0) {
> + if (err_type < ARRAY_SIZE(_invalid_trnslt_desc))
> + pr_cont("%s\n",
> + _invalid_trnslt_desc[err_type]);
> + } else {
> + if (err_type < ARRAY_SIZE(_invalid_trnsac_desc))
> + pr_cont("%s\n",
> + _invalid_trnsac_desc[err_type]);
> + }
> + }
> +}
> +
> +static void dump_flags(int flags, int ev_type)
> +{
> + struct _event_log_flags *p = (struct _event_log_flags *) &flags;
> + u32 err_type = p->type;
> +
> + pr_cont(" flags:%s %s %s %s %s %s %s %s %s",
> + (p->gn ? "G" : "N"),
> + (p->nx ? "Nx" : "Ex"),
> + (p->us ? "Usr" : "Sup"),
> + (p->i ? "I" : "M"),
> + (p->pr ? "P" : "NP"),
> + (p->rw ? "W" : "R"),
> + (p->pe ? "N-Pm" : "Pm"),
> + (p->rz ? "Rsv" : "Ill"),
> + (p->tr ? "Tl" : "Ta"));
> +

Good feature. Do you also plan to add decode logic for these flags.
For example, RZ is only meaningful when PR=1, RW is only meaningful
when
PR=1, TR=0, and I=0, and so on? This additional logic will be useful.

Reviewed-by: Shuah Khan <shuahkhan@xxxxxxxxx>

-- Shuah


> + /* Error type only needed for certain events */
> + if (!amd_iommu_verbose) {
> + if ((ev_type == EVENT_TYPE_DEV_TAB_ERR) ||
> + (ev_type == EVENT_TYPE_PAGE_TAB_ERR) ||
> + (ev_type == EVENT_TYPE_CMD_HARD_ERR) ||
> + (ev_type == EVENT_TYPE_INV_DEV_REQ))
> + pr_cont(" type(0x%x)]\n", err_type);
> + } else {
> + pr_cont("]\n");
> + dump_detail_error(p, ev_type);
> + }
> +}
> +
> static void dump_dte_entry(u16 devid)
> {
> int i;
>
> + pr_err("AMD-Vi: DTE[0..3]:");
> for (i = 0; i < 4; ++i)
> - pr_err("AMD-Vi: DTE[%d]: %016llx\n", i,
> - amd_iommu_dev_table[devid].data[i]);
> + pr_cont(" %016llx", amd_iommu_dev_table[devid].data[i]);
> + pr_cont("\n");
> }
>
> static void dump_command(unsigned long phys_addr)
> @@ -619,81 +724,96 @@ 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(struct amd_iommu *iommu, void *__evt)
> +void amd_iommu_print_event(int type, int devid, int domid,
> + int flags, u64 address)
> {
> - int type, devid, domid, flags;
> - volatile u32 *event = __evt;
> - int count = 0;
> - u64 address;
> -
> -retry:
> - type = (event[1] >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
> - devid = (event[0] >> EVENT_DEVID_SHIFT) & EVENT_DEVID_MASK;
> - domid = (event[1] >> EVENT_DOMID_SHIFT) & EVENT_DOMID_MASK;
> - flags = (event[1] >> EVENT_FLAGS_SHIFT) & EVENT_FLAGS_MASK;
> - address = (u64)(((u64)event[3]) << 32) | event[2];
> -
> - if (type == 0) {
> - /* Did we hit the erratum? */
> - if (++count == LOOP_TIMEOUT) {
> - pr_err("AMD-Vi: No event written to event log\n");
> - return;
> - }
> - udelay(1);
> - goto retry;
> - }
> -
> - printk(KERN_ERR "AMD-Vi: Event logged [");
> + pr_err("AMD-Vi: Event logged [");
>
> switch (type) {
> case EVENT_TYPE_ILL_DEV:
> - printk("ILLEGAL_DEV_TABLE_ENTRY device=%02x:%02x.%x "
> - "address=0x%016llx flags=0x%04x]\n",
> + pr_cont("ILLEGAL_DEV_TABLE_ENTRY device=%02x:%02x.%x "
> + "address=0x%016llx",
> PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> - address, flags);
> + address);
> + dump_flags(flags, type);
> dump_dte_entry(devid);
> break;
> case EVENT_TYPE_IO_FAULT:
> - printk("IO_PAGE_FAULT device=%02x:%02x.%x "
> - "domain=0x%04x address=0x%016llx flags=0x%04x]\n",
> + pr_cont("IO_PAGE_FAULT device=%02x:%02x.%x "
> + "domain=0x%04x address=0x%016llx",
> PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> - domid, address, flags);
> + domid, address);
> + dump_flags(flags, type);
> + dump_dte_entry(devid);
> break;
> case EVENT_TYPE_DEV_TAB_ERR:
> - printk("DEV_TAB_HARDWARE_ERROR device=%02x:%02x.%x "
> - "address=0x%016llx flags=0x%04x]\n",
> + pr_cont("DEV_TAB_HARDWARE_ERROR device=%02x:%02x.%x "
> + "address=0x%016llx",
> PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> - address, flags);
> + address);
> + dump_flags(flags, type);
> break;
> case EVENT_TYPE_PAGE_TAB_ERR:
> - printk("PAGE_TAB_HARDWARE_ERROR device=%02x:%02x.%x "
> - "domain=0x%04x address=0x%016llx flags=0x%04x]\n",
> + pr_cont("PAGE_TAB_HARDWARE_ERROR device=%02x:%02x.%x "
> + "domain=0x%04x address=0x%016llx",
> PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> - domid, address, flags);
> + domid, address);
> + dump_flags(flags, type);
> break;
> case EVENT_TYPE_ILL_CMD:
> - printk("ILLEGAL_COMMAND_ERROR address=0x%016llx]\n", address);
> + pr_cont("ILLEGAL_COMMAND_ERROR address=0x%016llx\n",
> + address);
> dump_command(address);
> break;
> case EVENT_TYPE_CMD_HARD_ERR:
> - printk("COMMAND_HARDWARE_ERROR address=0x%016llx "
> - "flags=0x%04x]\n", address, flags);
> + pr_cont("COMMAND_HARDWARE_ERROR address=0x%016llx",
> + address);
> + dump_flags(flags, type);
> break;
> case EVENT_TYPE_IOTLB_INV_TO:
> - printk("IOTLB_INV_TIMEOUT device=%02x:%02x.%x "
> + pr_cont("IOTLB_INV_TIMEOUT device=%02x:%02x.%x "
> "address=0x%016llx]\n",
> PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> address);
> break;
> case EVENT_TYPE_INV_DEV_REQ:
> - printk("INVALID_DEVICE_REQUEST device=%02x:%02x.%x "
> - "address=0x%016llx flags=0x%04x]\n",
> + pr_cont("INVALID_DEVICE_REQUEST device=%02x:%02x.%x "
> + "address=0x%016llx",
> PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
> - address, flags);
> + address);
> + dump_flags(flags, type);
> + dump_dte_entry(devid);
> break;
> default:
> - printk(KERN_ERR "UNKNOWN type=0x%02x]\n", type);
> + pr_cont("UNKNOWN type=0x%02x\n", type);
> }
> +}
> +
> +static void iommu_handle_event(struct amd_iommu *iommu, void *__evt)
> +{
> + int type, devid, domid, flags;
> + u32 *event = __evt;
> + int count = 0;
> + u64 address;
> +
> +retry:
> + type = (event[1] >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
> + devid = (event[0] >> EVENT_DEVID_SHIFT) & EVENT_DEVID_MASK;
> + domid = (event[1] >> EVENT_DOMID_SHIFT) & EVENT_DOMID_MASK;
> + flags = (event[1] >> EVENT_FLAGS_SHIFT) & EVENT_FLAGS_MASK;
> + address = (u64)(((u64)event[3]) << 32) | event[2];
> +
> + if (type == 0) {
> + /* Did we hit the erratum? */
> + if (++count == LOOP_TIMEOUT) {
> + pr_err("AMD-Vi: No event written to event log\n");
> + return;
> + }
> + udelay(1);
> + goto retry;
> + }
> +
> + amd_iommu_print_event(type, devid, domid, flags, address);
>
> memset(__evt, 0, 4 * sizeof(u32));
> }
> @@ -709,7 +829,7 @@ 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, iommu->evt_buf + head);
> + iommu_handle_event(iommu, iommu->evt_buf + head);
> head = (head + EVENT_ENTRY_SIZE) % iommu->evt_buf_size;
> }
>
> @@ -3268,6 +3388,7 @@ static int __init alloc_passthrough_domain(void)
>
> return 0;
> }
> +
> static int amd_iommu_domain_init(struct iommu_domain *dom)
> {
> struct protection_domain *domain;
> --
> 1.7.10.4
>
>
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