Subject: Re: [PATCH v3] powerpc/pseries/eeh: Fix pseries_eeh_err_inject

From: Ritesh Harjani (IBM) <[email-masked]>
Date: Tue, 24 Sep 2024 08:23:18 +0530

Guenter Roeck <[email-masked]> writes:

> Hi,
>
> On Mon, Sep 09, 2024 at 09:02:20AM -0500, Narayana Murty N wrote:
>> VFIO_EEH_PE_INJECT_ERR ioctl is currently failing on pseries
>> due to missing implementation of err_inject eeh_ops for pseries.
>> This patch implements pseries_eeh_err_inject in eeh_ops/pseries
>> eeh_ops. Implements support for injecting MMIO load/store error
>> for testing from user space.
>> 
>> The check on PCI error type (bus type) code is moved to platform
>> code, since the eeh_pe_inject_err can be allowed to more error
>> types depending on platform requirement. Removal of the check for
>> 'type' in eeh_pe_inject_err() doesn't impact PowerNV as
>> pnv_eeh_err_inject() already has an equivalent check in place.
>> 
>> Signed-off-by: Narayana Murty N <[email-masked]>
>> Reviewed-by: Vaibhav Jain <[email-masked]>
>> 
>> ---
>>  arch/powerpc/include/asm/eeh.h               |  2 +-
>>  arch/powerpc/kernel/eeh.c                    |  9 +++--
>>  arch/powerpc/platforms/pseries/eeh_pseries.c | 39 +++++++++++++++++++-
>>  3 files changed, 44 insertions(+), 6 deletions(-)
>> 
>> diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
>> index 91a9fd53254f..317b12fc1fe4 100644
>> --- a/arch/powerpc/include/asm/eeh.h
>> +++ b/arch/powerpc/include/asm/eeh.h
>> @@ -308,7 +308,7 @@ int eeh_pe_reset(struct eeh_pe *pe, int option, bool include_passed);
>>  int eeh_pe_configure(struct eeh_pe *pe);
>>  int eeh_pe_inject_err(struct eeh_pe *pe, int type, int func,
>>  		      unsigned long addr, unsigned long mask);
>> -
>> +int eeh_pe_inject_mmio_error(struct pci_dev *pdev);
>>  /**
>>   * EEH_POSSIBLE_ERROR() -- test for possible MMIO failure.
>>   *
>> diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c
>> index d03f17987fca..49ab11a287a3 100644
>> --- a/arch/powerpc/kernel/eeh.c
>> +++ b/arch/powerpc/kernel/eeh.c
>> @@ -1537,10 +1537,6 @@ int eeh_pe_inject_err(struct eeh_pe *pe, int type, int func,
>>  	if (!eeh_ops || !eeh_ops->err_inject)
>>  		return -ENOENT;
>>  
>> -	/* Check on PCI error type */
>> -	if (type != EEH_ERR_TYPE_32 && type != EEH_ERR_TYPE_64)
>> -		return -EINVAL;
>> -
>>  	/* Check on PCI error function */
>>  	if (func < EEH_ERR_FUNC_MIN || func > EEH_ERR_FUNC_MAX)
>>  		return -EINVAL;
>> @@ -1851,6 +1847,11 @@ static const struct file_operations eeh_dev_break_fops = {
>>  	.read   = eeh_debugfs_dev_usage,
>>  };
>>  
>> +int eeh_pe_inject_mmio_error(struct pci_dev *pdev)
>> +{
>> +	return eeh_debugfs_break_device(pdev);
>> +}
>> +
>
> The new function, as the context suggests, is only compiled if CONFIG_DEBUG_FS=y.
> However, it is called unconditionally. With CONFIG_DEBUG_FS=n, this results in
>
> powerpc64-linux-ld: arch/powerpc/platforms/pseries/eeh_pseries.o: in function `pseries_eeh_err_inject':
> /opt/buildbot/slave/qemu-ppc64/build/arch/powerpc/platforms/pseries/eeh_pseries.c:814:(.text+0x554): undefined reference to `eeh_pe_inject_mmio_error'
> make[3]: *** [/opt/buildbot/slave/qemu-ppc64/build/scripts/Makefile.vmlinux:34: vmlinux] Error 1
> make[2]: *** [/opt/buildbot/slave/qemu-ppc64/build/Makefile:1157: vmlinux] Error 2
>
> I'll enable CONFIG_DEBUG_FS in my tests and won't report this further,
> but you might want to consider fixing the problem at some point.
>

Yes, this is fixed and picked up in powerpc tree.

https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?h=merge&id=3af2e2f68cc6baf0a11f662d30b0bf981f77bfea

-ritesh