From: Oded Gabbay Date: Sun, 5 Jun 2022 09:56:36 +0000 (+0300) Subject: habanalabs/gaudi: fix comment to reflect current code X-Git-Tag: v6.6.17~6911^2~27^2~80 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=8742a75a1c3f4c93efedfa5004d18c87e467ca3b;p=platform%2Fkernel%2Flinux-rpi.git habanalabs/gaudi: fix comment to reflect current code Due to code changes in the past few years, the original comment of how parser->user_cb_size is checked was not correct anymore. Fix it to reflect current code and add more explanation as the code is more complex now. Reported-by: Dan Carpenter Signed-off-by: Oded Gabbay --- diff --git a/drivers/misc/habanalabs/gaudi/gaudi.c b/drivers/misc/habanalabs/gaudi/gaudi.c index c16c0f9..72b0d145 100644 --- a/drivers/misc/habanalabs/gaudi/gaudi.c +++ b/drivers/misc/habanalabs/gaudi/gaudi.c @@ -5562,8 +5562,14 @@ static int gaudi_parse_cb_mmu(struct hl_device *hdev, } /* - * The check that parser->user_cb_size <= parser->user_cb->size was done - * in validate_queue_index(). + * We are protected from overflow because the check + * "parser->user_cb_size <= parser->user_cb->size" was done in get_cb_from_cs_chunk() + * in the common code. That check is done only if is_kernel_allocated_cb is true. + * + * There is no option to reach here without going through that check because: + * 1. validate_queue_index() assigns true to is_kernel_allocated_cb for any submission to + * an external queue. + * 2. For Gaudi, we only parse CBs that were submitted to the external queues. */ memcpy(parser->patched_cb->kernel_address, parser->user_cb->kernel_address,