Re: [PATCH] ACPI / APEI: release resources if gen_pool_add fails

[James Morse <james.morse@arm.com>]

Hi Liguang,

On 14/06/2019 10:49, luanshi wrote:
> To avoid memory leaks, destroy ghes_estatus_pool and release memory
> allocated via vmalloc() on errors in ghes_estatus_pool_init().
> 
> Signed-off-by: liguang.zlg <zhangliguang@linux.alibaba.com>

(I'm surprised your name has a '.' in it!)

Nit: This is v2. Please add a version number in the subject, e.g.:
| [PATCH v2] ACPI / APEI: release resources if gen_pool_add fails

This makes it easy for reviewers to know which is the latest. git format-patch will do
this for you if you add '-v 2' to its command-line.


> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
> index 993940d..8472c96 100644
> --- a/drivers/acpi/apei/ghes.c
> +++ b/drivers/acpi/apei/ghes.c
> @@ -163,8 +164,10 @@ int ghes_estatus_pool_init(int num_ghes)
>  
>  	ghes_estatus_pool_size_request = PAGE_ALIGN(len);
>  	addr = (unsigned long)vmalloc(PAGE_ALIGN(len));
> -	if (!addr)
> +	if (!addr) {
> +		gen_pool_destroy(ghes_estatus_pool);
>  		return -ENOMEM;
> +	}
>  
>  	/*
>  	 * New allocation must be visible in all pgd before it can be found by
> @@ -172,7 +175,12 @@ int ghes_estatus_pool_init(int num_ghes)
>  	 */
>  	vmalloc_sync_all();
>  
> -	return gen_pool_add(ghes_estatus_pool, addr, PAGE_ALIGN(len), -1);
> +	rc = gen_pool_add(ghes_estatus_pool, addr, PAGE_ALIGN(len), -1);
> +	if (rc) {

> +		vfree(addr);

addr here is unsigned long, but vfree() wants a void *.

vfree() first leaves us with a pool containing memory we've vfree()d, which doesn't feel
like a good state to step through.
Can we vfree() after gen_pool_destroy()?


> +		gen_pool_destroy(ghes_estatus_pool);
> +	}
> +	return rc;
>  }


With that:
Reviewed-by: James Morse <james.morse@arm.com>
Tested-by: James Morse <james.morse@arm.com>


Thanks for cleaning this up!

James