Re: [PATCH] ocxl: Fix access to the AFU Descriptor Data

Le 13/08/2018 à 11:48, Andrew Donnellan a écrit :

On 13/08/18 19:01, Christophe Lombard wrote:

quoted

From: Christophe Lombard <redacted>

Your git committer email should probably match your sign-off email.

quoted

The AFU Information DVSEC capability is a means to extract common,
general information about all of the AFUs associated with a Function
independent of the specific functionality that each AFU provides.

This patch fixes the access to the AFU Descriptor Data indexed by the
AFU Info Index field.

Fixes: 5ef3166e8a32 ("ocxl: Driver code for 'generic' opencapi devices")

Signed-off-by: Christophe Lombard <redacted>

This looks like it should go to stable? I assume the reason we haven't 
noticed this previously is because we have not been testing with 
multi-AFU cards.

Yes, it's hidden until we have more than one AFU per function. Also, the 
field we overwrite at the wrong offset is read-only, so it goes undetected.

   Fred

quoted

---
  drivers/misc/ocxl/config.c | 4 +++-
  1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/ocxl/config.c b/drivers/misc/ocxl/config.c
index 2e30de9..de01623 100644
--- a/drivers/misc/ocxl/config.c
+++ b/drivers/misc/ocxl/config.c

@@ -280,7 +280,9 @@ int ocxl_config_check_afu_index(struct pci_dev *dev,

      u32 val;
      int rc, templ_major, templ_minor, len;
-    pci_write_config_word(dev, fn->dvsec_afu_info_pos, afu_idx);
+    pci_write_config_word(dev,
+                  fn->dvsec_afu_info_pos + OCXL_DVSEC_AFU_INFO_AFU_IDX,
+                  afu_idx);

pci_write_config_byte() would be more appropriate here (see 
ocxl_config_read_afu() at line 454)

quoted

      rc = read_afu_info(dev, fn, OCXL_DVSEC_TEMPL_VERSION, &val);
      if (rc)
          return rc;