Re: [PATCH v3 2/2] drivers/vfio: Support EEH error injection

[David Gibson <david@gibson.dropbear.id.au>]

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On Mon, Mar 23, 2015 at 12:56:36PM +1100, Gavin Shan wrote:
> On Mon, Mar 23, 2015 at 12:39:45PM +1100, David Gibson wrote:
> >On Sat, Mar 21, 2015 at 06:58:45AM +1100, Gavin Shan wrote:
> >> The patch adds one more EEH sub-command (VFIO_EEH_PE_INJECT_ERR)
> >> to inject the specified EEH error, which is represented by
> >> (struct vfio_eeh_pe_err), to the indicated PE for testing purpose.
> >> 
> >> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
> >
> >Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> >
> >> ---
> >>  Documentation/vfio.txt        | 12 ++++++++++++
> >>  drivers/vfio/vfio_spapr_eeh.c | 10 ++++++++++
> >>  include/uapi/linux/vfio.h     | 36 +++++++++++++++++++++++++++++++++++-
> >>  3 files changed, 57 insertions(+), 1 deletion(-)
> >> 
> >> diff --git a/Documentation/vfio.txt b/Documentation/vfio.txt
> >> index 96978ec..c6e11a3 100644
> >> --- a/Documentation/vfio.txt
> >> +++ b/Documentation/vfio.txt
> >> @@ -385,6 +385,18 @@ The code flow from the example above should be slightly changed:
> >>  
> >>  	....
> >>  
> >> +	/* Inject EEH error, which is expected to be caused by 32-bits
> >> +	 * config load.
> >> +	 */
> >> +	pe_op.op = VFIO_EEH_PE_INJECT_ERR;
> >> +	pe_op.err.type = VFIO_EEH_ERR_TYPE_32;
> >> +	pe_op.err.func = VFIO_EEH_ERR_FUNC_LD_CFG_ADDR;
> >> +	pe_op.err.addr = 0ul;
> >> +	pe_op.err.mask = 0ul;
> >> +	ioctl(container, VFIO_EEH_PE_OP, &pe_op);
> >> +
> >> +	....
> >> +
> >>  	/* When 0xFF's returned from reading PCI config space or IO BARs
> >>  	 * of the PCI device. Check the PE's state to see if that has been
> >>  	 * frozen.
> >> diff --git a/drivers/vfio/vfio_spapr_eeh.c b/drivers/vfio/vfio_spapr_eeh.c
> >> index 5fa42db..38edeb4 100644
> >> --- a/drivers/vfio/vfio_spapr_eeh.c
> >> +++ b/drivers/vfio/vfio_spapr_eeh.c
> >> @@ -85,6 +85,16 @@ long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
> >>  		case VFIO_EEH_PE_CONFIGURE:
> >>  			ret = eeh_pe_configure(pe);
> >>  			break;
> >> +		case VFIO_EEH_PE_INJECT_ERR:
> >> +			minsz = offsetofend(struct vfio_eeh_pe_op, err.mask);
> >> +			if (op.argsz < minsz)
> >> +				return -EINVAL;
> >> +			if (copy_from_user(&op, (void __user *)arg, minsz))
> >> +				return -EFAULT;
> >> +
> >> +			ret = eeh_pe_inject_err(pe, op.err.type, op.err.func,
> >> +						op.err.addr, op.err.mask);
> >> +			break;
> >>  		default:
> >>  			ret = -EINVAL;
> >>  		}
> >> diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
> >> index 82889c3..f68e962 100644
> >> --- a/include/uapi/linux/vfio.h
> >> +++ b/include/uapi/linux/vfio.h
> >> @@ -468,12 +468,23 @@ struct vfio_iommu_spapr_tce_info {
> >>   * - unfreeze IO/DMA for frozen PE;
> >>   * - read PE state;
> >>   * - reset PE;
> >> - * - configure PE.
> >> + * - configure PE;
> >> + * - inject EEH error.
> >>   */
> >> +struct vfio_eeh_pe_err {
> >> +	__u32 type;
> >> +	__u32 func;
> >> +	__u64 addr;
> >> +	__u64 mask;
> >> +};
> >> +
> >>  struct vfio_eeh_pe_op {
> >>  	__u32 argsz;
> >>  	__u32 flags;
> >>  	__u32 op;
> >> +	union {
> >> +		struct vfio_eeh_pe_err err;
> >> +	};
> >>  };
> >>  
> >>  #define VFIO_EEH_PE_DISABLE		0	/* Disable EEH functionality */
> >> @@ -490,6 +501,29 @@ struct vfio_eeh_pe_op {
> >>  #define VFIO_EEH_PE_RESET_HOT		6	/* Assert hot reset          */
> >>  #define VFIO_EEH_PE_RESET_FUNDAMENTAL	7	/* Assert fundamental reset  */
> >>  #define VFIO_EEH_PE_CONFIGURE		8	/* PE configuration          */
> >> +#define VFIO_EEH_PE_INJECT_ERR		9	/* Inject EEH error          */
> >> +#define  VFIO_EEH_ERR_TYPE_32		0	/* 32-bits EEH error type    */
> >> +#define  VFIO_EEH_ERR_TYPE_64		1	/* 64-bits EEH error type    */
> >> +#define  VFIO_EEH_ERR_FUNC_LD_MEM_ADDR		0	/* Memory load  */
> >> +#define  VFIO_EEH_ERR_FUNC_LD_MEM_DATA		1
> >> +#define  VFIO_EEH_ERR_FUNC_LD_IO_ADDR		2	/* IO load      */
> >> +#define  VFIO_EEH_ERR_FUNC_LD_IO_DATA		3
> >> +#define  VFIO_EEH_ERR_FUNC_LD_CFG_ADDR		4	/* Config load  */
> >> +#define  VFIO_EEH_ERR_FUNC_LD_CFG_DATA		5
> >> +#define  VFIO_EEH_ERR_FUNC_ST_MEM_ADDR		6	/* Memory store */
> >> +#define  VFIO_EEH_ERR_FUNC_ST_MEM_DATA		7
> >> +#define  VFIO_EEH_ERR_FUNC_ST_IO_ADDR		8	/* IO store     */
> >> +#define  VFIO_EEH_ERR_FUNC_ST_IO_DATA		9
> >> +#define  VFIO_EEH_ERR_FUNC_ST_CFG_ADDR		10	/* Config store */
> >> +#define  VFIO_EEH_ERR_FUNC_ST_CFG_DATA		11
> >> +#define  VFIO_EEH_ERR_FUNC_DMA_RD_ADDR		12	/* DMA read     */
> >> +#define  VFIO_EEH_ERR_FUNC_DMA_RD_DATA		13
> >> +#define  VFIO_EEH_ERR_FUNC_DMA_RD_MASTER	14
> >> +#define  VFIO_EEH_ERR_FUNC_DMA_RD_TARGET	15
> >> +#define  VFIO_EEH_ERR_FUNC_DMA_WR_ADDR		16	/* DMA write    */
> >> +#define  VFIO_EEH_ERR_FUNC_DMA_WR_DATA		17
> >> +#define  VFIO_EEH_ERR_FUNC_DMA_WR_MASTER	18
> >> +#define  VFIO_EEH_ERR_FUNC_DMA_WR_TARGET	19
> >
> >These all seem to duplicate (under slightly different names) the
> >defines you just added in arch/powerpc/include/asm/eeh.h.  It would
> >make more sense to only have the uapi copy, surely.
> >
> 
> David, Thanks for your time. The defines in eeh.h is used not only
> for mapping those constants defined in vfio.h, but also for validating
> arguments from debugfs entry "err_injct". So it'd better to keep
> them separate: one set is used by userspace, another set is used
> by host kernel.

I don't understand why this is an argument for duplicating them.  They
have the same meanings and values, why can't you use the uapi versions
everywhere?

> By the way, Alex Williamson, could you please ACK this if you don't
> find obvious errors in the patch. I really want this to be merged
> to 4.1.
> 
> Thanks,
> Gavin 
> 
> 
> 

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

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