lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [day] [month] [year] [list]
Message-ID: <SJ0PR18MB390077BA38838F7BDA2C57C5A1E89@SJ0PR18MB3900.namprd18.prod.outlook.com>
Date:   Thu, 22 Dec 2022 09:38:41 +0000
From:   Alok Prasad <palok@...vell.com>
To:     "csander@...estorage.com" <csander@...estorage.com>,
        Ariel Elior <aelior@...vell.com>,
        Manish Chopra <manishc@...vell.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>
CC:     "joern@...estorage.com" <joern@...estorage.com>,
        "csander@...estorage.com" <csander@...estorage.com>
Subject: RE: [PATCH] qed: allow sleep in qed_mcp_trace_dump()

> -----Original Message-----
> From: Caleb Sander <csander@...estorage.com>
> Sent: Saturday, December 17, 2022 7:56 PM
> To: Ariel Elior <aelior@...vell.com>; Manish Chopra 
> <manishc@...vell.com>; netdev@...r.kernel.org
> Cc: Joern Engel <joern@...estorage.com>; Caleb Sander 
> <csander@...estorage.com>
> Subject: [EXT] [PATCH] qed: allow sleep in qed_mcp_trace_dump()
> 
> External Email
> 
> ----------------------------------------------------------------------
> By default, qed_mcp_cmd_and_union() waits for 10us at a time in a loop 
> that can run 500K times, so calls to qed_mcp_nvm_rd_cmd() may block 
> the current thread for over 5s.
> We observed thread scheduling delays of over 700ms in production, with 
> stacktraces pointing to this code as the culprit.
> 
> qed_mcp_trace_dump() is called from ethtool, so sleeping is permitted.
> It already can sleep in qed_mcp_halt(), which calls qed_mcp_cmd().
> Add a "can sleep" parameter to qed_find_nvram_image() and
> qed_nvram_read() so they can sleep during qed_mcp_trace_dump().
> qed_mcp_trace_get_meta_info() and qed_mcp_trace_read_meta(), called 
> only by qed_mcp_trace_dump(), allow these functions to sleep.
> It's not clear to me that the other caller 
> (qed_grc_dump_mcp_hw_dump()) can sleep, so it keeps b_can_sleep set to false.
> 
> Signed-off-by: Caleb Sander <csander@...estorage.com>
> ---
>  drivers/net/ethernet/qlogic/qed/qed_debug.c | 28 +++++++++++++++-----
> -
>  1 file changed, 20 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/net/ethernet/qlogic/qed/qed_debug.c
> b/drivers/net/ethernet/qlogic/qed/qed_debug.c
> index 86ecb080b153..cdcead614e9f 100644
> --- a/drivers/net/ethernet/qlogic/qed/qed_debug.c
> +++ b/drivers/net/ethernet/qlogic/qed/qed_debug.c
> @@ -1830,11 +1830,12 @@ static void qed_grc_clear_all_prty(struct 
> qed_hwfn *p_hwfn,
>  /* Finds the meta data image in NVRAM */  static enum dbg_status 
> qed_find_nvram_image(struct qed_hwfn *p_hwfn,
>  					    struct qed_ptt *p_ptt,
>  					    u32 image_type,
>  					    u32 *nvram_offset_bytes,
> -					    u32 *nvram_size_bytes)
> +					    u32 *nvram_size_bytes,
> +					    bool b_can_sleep)
>  {
>  	u32 ret_mcp_resp, ret_mcp_param, ret_txn_size;
>  	struct mcp_file_att file_att;
>  	int nvm_result;
> 
> @@ -1844,11 +1845,12 @@ static enum dbg_status 
> qed_find_nvram_image(struct qed_hwfn *p_hwfn,
> 
> 	DRV_MSG_CODE_NVM_GET_FILE_ATT,
>  					image_type,
>  					&ret_mcp_resp,
>  					&ret_mcp_param,
>  					&ret_txn_size,
> -					(u32 *)&file_att, false);
> +					(u32 *)&file_att,
> +					b_can_sleep);
> 
>  	/* Check response */
>  	if (nvm_result || (ret_mcp_resp & FW_MSG_CODE_MASK) !=
>  	    FW_MSG_CODE_NVM_OK)
>  		return DBG_STATUS_NVRAM_GET_IMAGE_FAILED;
> @@ -1871,11 +1873,13 @@ static enum dbg_status 
> qed_find_nvram_image(struct qed_hwfn *p_hwfn,
> 
>  /* Reads data from NVRAM */
>  static enum dbg_status qed_nvram_read(struct qed_hwfn *p_hwfn,
>  				      struct qed_ptt *p_ptt,
>  				      u32 nvram_offset_bytes,
> -				      u32 nvram_size_bytes, u32 *ret_buf)
> +				      u32 nvram_size_bytes,
> +				      u32 *ret_buf,
> +				      bool b_can_sleep)
>  {
>  	u32 ret_mcp_resp, ret_mcp_param, ret_read_size, bytes_to_copy;
>  	s32 bytes_left = nvram_size_bytes;
>  	u32 read_offset = 0, param = 0;
> 
> @@ -1897,11 +1901,11 @@ static enum dbg_status qed_nvram_read(struct 
> qed_hwfn *p_hwfn,
>  		if (qed_mcp_nvm_rd_cmd(p_hwfn, p_ptt,
>  				       DRV_MSG_CODE_NVM_READ_NVRAM, param,
>  				       &ret_mcp_resp,
>  				       &ret_mcp_param, &ret_read_size,
>  				       (u32 *)((u8 *)ret_buf + read_offset),
> -				       false))
> +				       b_can_sleep))
>  			return DBG_STATUS_NVRAM_READ_FAILED;
> 
>  		/* Check response */
>  		if ((ret_mcp_resp & FW_MSG_CODE_MASK) !=
> FW_MSG_CODE_NVM_OK)
>  			return DBG_STATUS_NVRAM_READ_FAILED; @@ -3378,11 +3382,12 @@ 
> static u32 qed_grc_dump_mcp_hw_dump(struct qed_hwfn *p_hwfn,
>  	/* Read HW dump image from NVRAM */
>  	status = qed_find_nvram_image(p_hwfn,
>  				      p_ptt,
>  				      NVM_TYPE_HW_DUMP_OUT,
>  				      &hw_dump_offset_bytes,
> -				      &hw_dump_size_bytes);
> +				      &hw_dump_size_bytes,
> +				      false);
>  	if (status != DBG_STATUS_OK)
>  		return 0;
> 
>  	hw_dump_size_dwords =
> BYTES_TO_DWORDS(hw_dump_size_bytes);
> 
> @@ -3395,11 +3400,13 @@ static u32 qed_grc_dump_mcp_hw_dump(struct 
> qed_hwfn *p_hwfn,
>  	/* Read MCP HW dump image into dump buffer */
>  	if (dump && hw_dump_size_dwords) {
>  		status = qed_nvram_read(p_hwfn,
>  					p_ptt,
>  					hw_dump_offset_bytes,
> -					hw_dump_size_bytes, dump_buf +
> offset);
> +					hw_dump_size_bytes,
> +					dump_buf + offset,
> +					false);
>  		if (status != DBG_STATUS_OK) {
>  			DP_NOTICE(p_hwfn,
>  				  "Failed to read MCP HW Dump image from NVRAM\n");
>  			return 0;
>  		}
> @@ -4121,11 +4128,13 @@ static enum dbg_status 
> qed_mcp_trace_get_meta_info(struct qed_hwfn *p_hwfn,
>  	    (*running_bundle_id ==
>  	     DIR_ID_1) ? NVM_TYPE_MFW_TRACE1 :
> NVM_TYPE_MFW_TRACE2;
>  	return qed_find_nvram_image(p_hwfn,
>  				    p_ptt,
>  				    nvram_image_type,
> -				    trace_meta_offset, trace_meta_size);
> +				    trace_meta_offset,
> +				    trace_meta_size,
> +				    true);
>  }
> 
>  /* Reads the MCP Trace meta data from NVRAM into the specified buffer 
> */  static enum dbg_status qed_mcp_trace_read_meta(struct qed_hwfn 
> *p_hwfn,
>  					       struct qed_ptt *p_ptt,
> @@ -4137,11 +4146,14 @@ static enum dbg_status 
> qed_mcp_trace_read_meta(struct qed_hwfn *p_hwfn,
>  	u32 signature;
> 
>  	/* Read meta data from NVRAM */
>  	status = qed_nvram_read(p_hwfn,
>  				p_ptt,
> -				nvram_offset_in_bytes, size_in_bytes, buf);
> +				nvram_offset_in_bytes,
> +				size_in_bytes,
> +				buf,
> +				true);
>  	if (status != DBG_STATUS_OK)
>  		return status;
> 
>  	/* Extract and check first signature */
>  	signature = qed_read_unaligned_dword(byte_buf);
> --
> 2.25.1

Thanks,

Acked-by: Alok Prasad <palok@...vell.com>


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ