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Date:   Thu, 10 Feb 2022 14:17:41 -0500
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Subject: Re: [PATCH] drm/amdkfd: fix loop error handling
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To:     trix@redhat.com, alexander.deucher@amd.com,
        christian.koenig@amd.com, Xinhui.Pan@amd.com, airlied@linux.ie,
        daniel@ffwll.ch, nathan@kernel.org, ndesaulniers@google.com,
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References: <20220210170418.2404807-1-trix@redhat.com>
From:   Felix Kuehling <felix.kuehling@amd.com>
In-Reply-To: <20220210170418.2404807-1-trix@redhat.com>
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Am 2022-02-10 um 12:04 schrieb trix@redhat.com:
> From: Tom Rix <trix@redhat.com>
>
> Clang static analysis reports this problem
> kfd_chardev.c:2594:16: warning: The expression is an uninitialized value.
>    The computed value will also be garbage
>          while (ret && i--) {
>                        ^~~
>
> i is a loop variable and this block unwinds a problem in the loop.
> When the error happens before the loop, this value is garbage.
> Move the initialization of i to its decalaration.
>
> Fixes: be072b06c739 ("drm/amdkfd: CRIU export BOs as prime dmabuf objects")
> Signed-off-by: Tom Rix <trix@redhat.com>

Thank you. I applied the patch to amd-staging-drm-next.

Regards,
   Felix


> ---
>   drivers/gpu/drm/amd/amdkfd/kfd_chardev.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
> index 636391c61cafb..4310ca07af130 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
> @@ -2374,7 +2374,7 @@ static int criu_restore_bos(struct kfd_process *p,
>   	const bool criu_resume = true;
>   	bool flush_tlbs = false;
>   	int ret = 0, j = 0;
> -	uint32_t i;
> +	uint32_t i = 0;
>   
>   	if (*priv_offset + (args->num_bos * sizeof(*bo_privs)) > max_priv_data_size)
>   		return -EINVAL;
> @@ -2410,7 +2410,7 @@ static int criu_restore_bos(struct kfd_process *p,
>   	*priv_offset += args->num_bos * sizeof(*bo_privs);
>   
>   	/* Create and map new BOs */
> -	for (i = 0; i < args->num_bos; i++) {
> +	for (; i < args->num_bos; i++) {
>   		struct kfd_criu_bo_bucket *bo_bucket;
>   		struct kfd_criu_bo_priv_data *bo_priv;
>   		struct kfd_dev *dev;