wil6210: Fix kernel oops in reset flow

wil_reset() removes vring's
At the same time NAPI may be active performing Rx/Tx completion.
If this happens, Rx/Tx polling functions going to access already removed vrings

Make sure NAPI is idle and won't be started prior to vring removal.
For this, track NAPI enabled state

Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Vladimir Kondratiev 2014-03-17 15:34:18 +02:00 committed by John W. Linville
parent 8bf6adb988
commit 0fef1818d0
3 changed files with 21 additions and 4 deletions

View File

@ -195,8 +195,12 @@ static irqreturn_t wil6210_irq_rx(int irq, void *cookie)
if (isr & BIT_DMA_EP_RX_ICR_RX_DONE) {
wil_dbg_irq(wil, "RX done\n");
isr &= ~BIT_DMA_EP_RX_ICR_RX_DONE;
wil_dbg_txrx(wil, "NAPI schedule\n");
napi_schedule(&wil->napi_rx);
if (test_bit(wil_status_reset_done, &wil->status)) {
wil_dbg_txrx(wil, "NAPI(Rx) schedule\n");
napi_schedule(&wil->napi_rx);
} else {
wil_err(wil, "Got Rx interrupt while in reset\n");
}
}
if (isr)
@ -226,10 +230,15 @@ static irqreturn_t wil6210_irq_tx(int irq, void *cookie)
if (isr & BIT_DMA_EP_TX_ICR_TX_DONE) {
wil_dbg_irq(wil, "TX done\n");
napi_schedule(&wil->napi_tx);
isr &= ~BIT_DMA_EP_TX_ICR_TX_DONE;
/* clear also all VRING interrupts */
isr &= ~(BIT(25) - 1UL);
if (test_bit(wil_status_reset_done, &wil->status)) {
wil_dbg_txrx(wil, "NAPI(Tx) schedule\n");
napi_schedule(&wil->napi_tx);
} else {
wil_err(wil, "Got Tx interrupt while in reset\n");
}
}
if (isr)

View File

@ -329,11 +329,16 @@ int wil_reset(struct wil6210_priv *wil)
{
int rc;
wil->status = 0; /* prevent NAPI from being scheduled */
if (test_bit(wil_status_napi_en, &wil->status)) {
napi_synchronize(&wil->napi_rx);
napi_synchronize(&wil->napi_tx);
}
cancel_work_sync(&wil->disconnect_worker);
wil6210_disconnect(wil, NULL);
wil6210_disable_irq(wil);
wil->status = 0;
wmi_event_flush(wil);
@ -426,6 +431,7 @@ static int __wil_up(struct wil6210_priv *wil)
napi_enable(&wil->napi_rx);
napi_enable(&wil->napi_tx);
set_bit(wil_status_napi_en, &wil->status);
return 0;
}
@ -443,6 +449,7 @@ int wil_up(struct wil6210_priv *wil)
static int __wil_down(struct wil6210_priv *wil)
{
clear_bit(wil_status_napi_en, &wil->status);
napi_disable(&wil->napi_rx);
napi_disable(&wil->napi_tx);

View File

@ -249,6 +249,7 @@ enum { /* for wil6210_priv.status */
wil_status_dontscan,
wil_status_reset_done,
wil_status_irqen, /* FIXME: interrupts enabled - for debug */
wil_status_napi_en, /* NAPI enabled protected by wil->mutex */
};
struct pci_dev;