lkml.org 
[lkml]   [2024]   [Jan]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH] scsi: ufs: core: Let the sq_lock protect sq_tail_slot access
From
On 12/18/2023 7:32 AM, Can Guo wrote:
> If access sq_tail_slot without the protection from the sq_lock, race
> condition can have multiple SQEs copied to duplicate SQE slot(s), which can
> lead to multiple incredible stability issues. Fix it by moving the *dest
> initialization, in ufshcd_send_command(), back under protection from the
> sq_lock.
>
> Fixes: 3c85f087faec ("scsi: ufs: mcq: Use pointer arithmetic in ufshcd_send_command()")
> Signed-off-by: Can Guo <quic_cang@quicinc.com>
>
> diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
> index ae9936f..2994aac 100644
> --- a/drivers/ufs/core/ufshcd.c
> +++ b/drivers/ufs/core/ufshcd.c
> @@ -2274,9 +2274,10 @@ void ufshcd_send_command(struct ufs_hba *hba, unsigned int task_tag,
> if (is_mcq_enabled(hba)) {
> int utrd_size = sizeof(struct utp_transfer_req_desc);
> struct utp_transfer_req_desc *src = lrbp->utr_descriptor_ptr;
> - struct utp_transfer_req_desc *dest = hwq->sqe_base_addr + hwq->sq_tail_slot;
> + struct utp_transfer_req_desc *dest;
>
> spin_lock(&hwq->sq_lock);
> + dest = hwq->sqe_base_addr + hwq->sq_tail_slot;
> memcpy(dest, src, utrd_size);
> ufshcd_inc_sq_tail(hwq);
> spin_unlock(&hwq->sq_lock);

Reviewed and Tested-by: Bao D. Nguyen <quic_nguyenb@quicinc.com>

\
 
 \ /
  Last update: 2024-01-02 21:35    [W:2.505 / U:0.004 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site