From 6cf18e6927c0b224f972e3042fb85770d63cb9f8 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 15 Feb 2017 11:11:51 +0100 Subject: [PATCH] goldfish: Sanitize the broken interrupt handler This interrupt handler is broken in several ways: - It loops forever when the op code is not decodeable - It never returns IRQ_HANDLED because the only way to exit the loop returns IRQ_NONE unconditionally. The whole concept of this is broken. Creating devices in an interrupt handler is beyond any point of sanity. Make it at least behave halfways sane so accidental users do not have to deal with a hard to debug lockup. Fixes: e809c22b8fb028 ("goldfish: add the goldfish virtual bus") Reported-by: Gabriel C Signed-off-by: Thomas Gleixner Acked-by: Linus Torvalds Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/platform/goldfish/pdev_bus.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/platform/goldfish/pdev_bus.c b/drivers/platform/goldfish/pdev_bus.c index 1f52462f4cdd..dd9ea463c2a4 100644 --- a/drivers/platform/goldfish/pdev_bus.c +++ b/drivers/platform/goldfish/pdev_bus.c @@ -157,23 +157,26 @@ static int goldfish_new_pdev(void) static irqreturn_t goldfish_pdev_bus_interrupt(int irq, void *dev_id) { irqreturn_t ret = IRQ_NONE; + while (1) { u32 op = readl(pdev_bus_base + PDEV_BUS_OP); - switch (op) { - case PDEV_BUS_OP_DONE: - return IRQ_NONE; + switch (op) { case PDEV_BUS_OP_REMOVE_DEV: goldfish_pdev_remove(); + ret = IRQ_HANDLED; break; case PDEV_BUS_OP_ADD_DEV: goldfish_new_pdev(); + ret = IRQ_HANDLED; break; + + case PDEV_BUS_OP_DONE: + default: + return ret; } - ret = IRQ_HANDLED; } - return ret; } static int goldfish_pdev_bus_probe(struct platform_device *pdev) -- GitLab