diff mbox series

[1/3] cxl/pci: Ignore unknown register block types

Message ID 20210716231548.174778-2-ben.widawsky@intel.com
State New, archived
Headers show
Series Rework register enumeration for later reuse | expand

Commit Message

Ben Widawsky July 16, 2021, 11:15 p.m. UTC 
In an effort to explicit avoid supporting vendor specific register
blocks (which can happily be mapped from userspace), entirely skip
probing unknown types. The secondary benefit of this will be revealed
in the future with code simplification.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
---
 drivers/cxl/pci.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

Comments

Jonathan Cameron Aug. 2, 2021, 3:49 p.m. UTC | #1 
On Fri, 16 Jul 2021 16:15:46 -0700
Ben Widawsky <ben.widawsky@intel.com> wrote:

> In an effort to explicit avoid supporting vendor specific register
> blocks (which can happily be mapped from userspace), entirely skip
> probing unknown types. The secondary benefit of this will be revealed
> in the future with code simplification.
> 
> Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Seems sensible even on it's own as we don't do anything with unknown
blocks anyway.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> ---
>  drivers/cxl/pci.c | 20 ++++++++++++--------
>  1 file changed, 12 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
> index d7da18ebba81..dd0ac89fbdf4 100644
> --- a/drivers/cxl/pci.c
> +++ b/drivers/cxl/pci.c
> @@ -1106,14 +1106,6 @@ static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
>  		u64 offset;
>  		u8 bar;
>  
> -		map = kzalloc(sizeof(*map), GFP_KERNEL);
> -		if (!map) {
> -			ret = -ENOMEM;
> -			goto free_maps;
> -		}
> -
> -		list_add(&map->list, &register_maps);
> -
>  		pci_read_config_dword(pdev, regloc, &reg_lo);
>  		pci_read_config_dword(pdev, regloc + 4, &reg_hi);
>  
> @@ -1123,6 +1115,18 @@ static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
>  		dev_dbg(dev, "Found register block in bar %u @ 0x%llx of type %u\n",
>  			bar, offset, reg_type);
>  
> +		/* Ignore unknown register block types */
> +		if (reg_type > CXL_REGLOC_RBI_MEMDEV)
> +			continue;
> +
> +		map = kzalloc(sizeof(*map), GFP_KERNEL);
> +		if (!map) {
> +			ret = -ENOMEM;
> +			goto free_maps;
> +		}
> +
> +		list_add(&map->list, &register_maps);
> +
>  		base = cxl_mem_map_regblock(cxlm, bar, offset);
>  		if (!base) {
>  			ret = -ENOMEM;
diff mbox series

Patch

diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index d7da18ebba81..dd0ac89fbdf4 100644
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -1106,14 +1106,6 @@  static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
 		u64 offset;
 		u8 bar;
 
-		map = kzalloc(sizeof(*map), GFP_KERNEL);
-		if (!map) {
-			ret = -ENOMEM;
-			goto free_maps;
-		}
-
-		list_add(&map->list, &register_maps);
-
 		pci_read_config_dword(pdev, regloc, &reg_lo);
 		pci_read_config_dword(pdev, regloc + 4, &reg_hi);
 
@@ -1123,6 +1115,18 @@  static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
 		dev_dbg(dev, "Found register block in bar %u @ 0x%llx of type %u\n",
 			bar, offset, reg_type);
 
+		/* Ignore unknown register block types */
+		if (reg_type > CXL_REGLOC_RBI_MEMDEV)
+			continue;
+
+		map = kzalloc(sizeof(*map), GFP_KERNEL);
+		if (!map) {
+			ret = -ENOMEM;
+			goto free_maps;
+		}
+
+		list_add(&map->list, &register_maps);
+
 		base = cxl_mem_map_regblock(cxlm, bar, offset);
 		if (!base) {
 			ret = -ENOMEM;