Re: [PATCH] b43: fix regression in PIO case

On Mon, 26 Dec 2011, Larry Finger wrote:

On 12/26/2011 11:28 AM, Guennadi Liakhovetski wrote:

quoted

This patch fixes the regression, introduced by

commit 17030f48e31adde5b043741c91ba143f5f7db0fd
From: Rafał Miłecki<zajec5@gmail.com>
Date: Thu, 11 Aug 2011 17:16:27 +0200
Subject: [PATCH] b43: support new RX header, noticed to be used in 598.314+
fw

in PIO case.

Signed-off-by: Guennadi Liakhovetski<redacted>
---

diff --git a/drivers/net/wireless/b43/pio.c b/drivers/net/wireless/b43/pio.c
index ce8a4bd..b64b64c 100644
--- a/drivers/net/wireless/b43/pio.c
+++ b/drivers/net/wireless/b43/pio.c

@@ -617,9 +617,19 @@ static bool pio_rx_frame(struct b43_pio_rxqueue *q)
  	const char *err_msg = NULL;
  	struct b43_rxhdr_fw4 *rxhdr =
  		(struct b43_rxhdr_fw4 *)wl->pio_scratchspace;
+	size_t rxhdr_size = sizeof(*rxhdr);

  	BUILD_BUG_ON(sizeof(wl->pio_scratchspace)<  sizeof(*rxhdr));
-	memset(rxhdr, 0, sizeof(*rxhdr));
+	switch (dev->fw.hdr_format) {
+	case B43_FW_HDR_410:
+	case B43_FW_HDR_351:
+		rxhdr_size -= sizeof(rxhdr->format_598) -
+			sizeof(rxhdr->format_351);
+		break;
+	case B43_FW_HDR_598:
+		break;
+	}

I do not think the above will work for format_410. By my count, the format_410
struct is 4 bytes longer than the format_351 struct.

I think you're looking at struct b43_txhdr, whereas the problem is in 
struct b43_rxhdr_fw4.

Thanks
Guennadi

Even if it does work, I suggest using the following:

	size_t rxhdr_size;

   	BUILD_BUG_ON(sizeof(wl->pio_scratchspace)<  sizeof(*rxhdr));
	switch (dev->fw.hdr_format) {
	case B43_FW_HDR_351:
		rxhdr_size = sizeof(rxhdr->format_351);
		break;
	case B43_FW_HDR_410:
etc.


Larry

---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/