Commit 42f6384f authored by Jiri Slaby's avatar Jiri Slaby Committed by Linus Torvalds
Browse files

[PATCH] Char: sx, lock boards struct 



Fix race condition which may occurs when multiple cards are probed at the same
time.  Add mutex to critical sections to avoid this situation.

Signed-off-by: default avatarJiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 927a6f9d

drivers/char/sx.c

+23 −14
Original line number Diff line number Diff line
@@ -298,6 +298,7 @@ static int sx_init_drivers(void); 


static struct tty_driver *sx_driver;



static DEFINE_MUTEX(sx_boards_lock);

static struct sx_board boards[SX_NBOARDS];

static struct sx_port *sx_ports;

static int sx_initialized;
@@ -1980,7 +1981,6 @@ static int sx_init_board (struct sx_board *board) 
	}



	if (chans) {

		/* board->flags |= SX_BOARD_PRESENT; */

		if(board->irq > 0) {

			/* fixed irq, probably PCI */

			if(sx_irqmask & (1 << board->irq)) { /* may we use this irq? */
@@ -2115,8 +2115,6 @@ static int __devinit probe_sx (struct sx_board *board) 
		return 0;

	sx_dprintk (SX_DEBUG_INIT, "reset the board...\n");



	board->flags |= SX_BOARD_PRESENT;



	func_exit();

	return 1;

}
@@ -2211,8 +2209,6 @@ static int __devinit probe_si (struct sx_board *board) 
		return 0;

	sx_dprintk (SX_DEBUG_INIT, "reset the board...\n");



	board->flags |= SX_BOARD_PRESENT;



	func_exit();

	return 1;

}
@@ -2396,10 +2392,15 @@ static int __devinit sx_eisa_probe(struct device *dev) 
	unsigned int i;

	int retval = -EIO;



	mutex_lock(&sx_boards_lock);

	i = sx_find_free_board();



	if (i == SX_NBOARDS)

	if (i == SX_NBOARDS) {

		mutex_unlock(&sx_boards_lock);

		goto err;

	}

	board = &boards[i];

	board->flags |= SX_BOARD_PRESENT;

	mutex_unlock(&sx_boards_lock);



	dev_info(dev, "XIO : Signature found in EISA slot %lu, "

			"Product %d Rev %d (REPORT THIS TO LKLM)\n",
@@ -2407,7 +2408,6 @@ static int __devinit sx_eisa_probe(struct device *dev) 
			inb(eisa_slot + EISA_VENDOR_ID_OFFSET + 2),

			inb(eisa_slot + EISA_VENDOR_ID_OFFSET + 3));



	board = &boards[i];

	board->eisa_base = eisa_slot;

	board->flags &= ~SX_BOARD_TYPE;

	board->flags |= SI_EISA_BOARD;
@@ -2430,6 +2430,7 @@ static int __devinit sx_eisa_probe(struct device *dev) 
	return 0;

err_unmap:

	iounmap(board->base);

	board->flags &= ~SX_BOARD_PRESENT;

err:

	return retval;

}
@@ -2498,16 +2499,19 @@ static int __devinit sx_pci_probe(struct pci_dev *pdev, 
	unsigned int i;

	int retval = -EIO;



	mutex_lock(&sx_boards_lock);

	i = sx_find_free_board();



	if (i == SX_NBOARDS)

	if (i == SX_NBOARDS) {

		mutex_unlock(&sx_boards_lock);

		goto err;

	}

	board = &boards[i];

	board->flags |= SX_BOARD_PRESENT;

	mutex_unlock(&sx_boards_lock);



	retval = pci_enable_device(pdev);

	if (retval)

		goto err;



	board = &boards[i];

		goto err_flag;



	board->flags &= ~SX_BOARD_TYPE;

	board->flags |= (pdev->subsystem_vendor == 0x200) ? SX_PCI_BOARD :
@@ -2522,7 +2526,7 @@ static int __devinit sx_pci_probe(struct pci_dev *pdev, 
	board->base = ioremap(board->hw_base, WINDOW_LEN (board));

	if (!board->base) {

		dev_err(&pdev->dev, "ioremap failed\n");

		goto err;

		goto err_flag;

	}



	/* Most of the stuff on the CF board is offset by 0x18000 ....  */
@@ -2546,6 +2550,8 @@ static int __devinit sx_pci_probe(struct pci_dev *pdev, 
	return 0;

err_unmap:

	iounmap(board->base2);

err_flag:

	board->flags &= ~SX_BOARD_PRESENT;

err:

	return retval;

}
@@ -2611,6 +2617,7 @@ static int __init sx_init(void) 
		board->irq = sx_irqmask?-1:0;



		if (probe_sx (board)) {

			board->flags |= SX_BOARD_PRESENT;

			found++;

		} else {

			iounmap(board->base);
@@ -2627,6 +2634,7 @@ static int __init sx_init(void) 
		board->irq = sx_irqmask ?-1:0;



		if (probe_si (board)) {

			board->flags |= SX_BOARD_PRESENT;

			found++;

		} else {

			iounmap (board->base);
@@ -2642,6 +2650,7 @@ static int __init sx_init(void) 
		board->irq = sx_irqmask ?-1:0;



		if (probe_si (board)) {

			board->flags |= SX_BOARD_PRESENT;

			found++;

		} else {

			iounmap (board->base);