From: Arend van Spriel <arend@broadcom.com>
Date: Wed, 5 Oct 2011 13:20:06 +0000 (+0200)
Subject: staging: brcm80211: fix thread blocking issue in brcmf_sdbrcm_bus_stop()
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=bbbf4f42f59e9e1412239102d055bcc1c5f54eaf;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git

staging: brcm80211: fix thread blocking issue in brcmf_sdbrcm_bus_stop()

The function brcmf_sdbrcm_bus_stop() terminates the watchdog and dpc
thread, but this function can be called from the dpc thread itself.
Stopping the dpc thread is only done when it is not the 'current'
thread.

Reviewed-by: Franky (Zhenhui) Lin <frankyl@broadcom.com>
Reviewed-by: Roland Vossen <rvossen@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/staging/brcm80211/brcmfmac/dhd_sdio.c b/drivers/staging/brcm80211/brcmfmac/dhd_sdio.c
index 0f7b80da41d0..6885755f4ec6 100644
--- a/drivers/staging/brcm80211/brcmfmac/dhd_sdio.c
+++ b/drivers/staging/brcm80211/brcmfmac/dhd_sdio.c
@@ -2694,7 +2694,10 @@ static int brcmf_sdbrcm_dpc_thread(void *data)
 				if (brcmf_sdbrcm_dpc(bus))
 					complete(&bus->dpc_wait);
 			} else {
+				/* after stopping the bus, exit thread */
 				brcmf_sdbrcm_bus_stop(bus);
+				bus->dpc_tsk = NULL;
+				break;
 			}
 		} else
 			break;
@@ -3601,25 +3604,25 @@ void brcmf_sdbrcm_bus_stop(struct brcmf_bus *bus)
 
 	brcmf_dbg(TRACE, "Enter\n");
 
-	down(&bus->sdsem);
-
-	bus_wake(bus);
-
-	/* Enable clock for device interrupts */
-	brcmf_sdbrcm_clkctl(bus, CLK_AVAIL, false);
-
 	if (bus->watchdog_tsk) {
 		send_sig(SIGTERM, bus->watchdog_tsk, 1);
 		kthread_stop(bus->watchdog_tsk);
 		bus->watchdog_tsk = NULL;
 	}
 
-	if (bus->dpc_tsk) {
+	if (bus->dpc_tsk && bus->dpc_tsk != current) {
 		send_sig(SIGTERM, bus->dpc_tsk, 1);
 		kthread_stop(bus->dpc_tsk);
 		bus->dpc_tsk = NULL;
 	}
 
+	down(&bus->sdsem);
+
+	bus_wake(bus);
+
+	/* Enable clock for device interrupts */
+	brcmf_sdbrcm_clkctl(bus, CLK_AVAIL, false);
+
 	/* Disable and clear interrupts at the chip level also */
 	w_sdreg32(bus, 0, offsetof(struct sdpcmd_regs, hostintmask), &retries);
 	local_hostintmask = bus->hostintmask;