[PATCH] pci/ehp_hpc: Convert timers to use timer_setup()

From: Kees Cook
Date: Wed Oct 04 2017 - 20:54:01 EST


In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly. This fixes what appears to be a bug
in passing the wrong pointer to the timer handler (address of ctrl pointer
instead of ctrl pointer).

Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Cc: Mayurkumar Patel <mayurkumar.patel@xxxxxxxxx>
Cc: Keith Busch <keith.busch@xxxxxxxxx>
Cc: linux-pci@xxxxxxxxxxxxxxx
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
This requires commit 686fef928bba ("timer: Prepare to change timer
callback argument type") in v4.14-rc3, but should be otherwise
stand-alone.
---
drivers/pci/hotplug/pciehp_hpc.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index e5d5ce9e3010..ba5055c5115c 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -50,14 +50,13 @@ static irqreturn_t pcie_isr(int irq, void *dev_id);
static void start_int_poll_timer(struct controller *ctrl, int sec);

/* This is the interrupt polling timeout function. */
-static void int_poll_timeout(unsigned long data)
+static void int_poll_timeout(struct timer_list *t)
{
- struct controller *ctrl = (struct controller *)data;
+ struct controller *ctrl = from_timer(ctrl, t, poll_timer);

/* Poll for interrupt events. regs == NULL => polling */
pcie_isr(0, ctrl);

- init_timer(&ctrl->poll_timer);
if (!pciehp_poll_time)
pciehp_poll_time = 2; /* default polling interval is 2 sec */

@@ -71,8 +70,6 @@ static void start_int_poll_timer(struct controller *ctrl, int sec)
if ((sec <= 0) || (sec > 60))
sec = 2;

- ctrl->poll_timer.function = &int_poll_timeout;
- ctrl->poll_timer.data = (unsigned long)ctrl;
ctrl->poll_timer.expires = jiffies + sec * HZ;
add_timer(&ctrl->poll_timer);
}
@@ -83,7 +80,7 @@ static inline int pciehp_request_irq(struct controller *ctrl)

/* Install interrupt polling timer. Start with 10 sec delay */
if (pciehp_poll_mode) {
- init_timer(&ctrl->poll_timer);
+ timer_setup(&ctrl->poll_timer, int_poll_timeout, 0);
start_int_poll_timer(ctrl, 10);
return 0;
}
@@ -764,8 +761,7 @@ int pciehp_reset_slot(struct slot *slot, int probe)
ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, ctrl_mask);
if (pciehp_poll_mode)
- int_poll_timeout(ctrl->poll_timer.data);
-
+ int_poll_timeout(&ctrl->poll_timer);
return 0;
}

--
2.7.4


--
Kees Cook
Pixel Security