Commit ad3c5412 authored by Gerd Hoffmann's avatar Gerd Hoffmann
Browse files

ehci: stop recursive calls to ehci_work_bh 



Can happen with usb-storage devices: ehci_work_bh calls usb-storage,
usb-storage calls into block layer, block layer may run BHs.

Add a simple bool and just do nothing in case we figure ehci_work_bh is
active.

Signed-off-by: default avatarGerd Hoffmann <kraxel@redhat.com>
Message-id: 20170612073109.25930-1-kraxel@redhat.com
parent d54fddea

hw/usb/hcd-ehci.c

+7 −0
Original line number Diff line number Diff line
@@ -2241,6 +2241,11 @@ static void ehci_work_bh(void *opaque) 
    uint64_t uframes, skipped_uframes;

    int i;



    if (ehci->working) {

        return;

    }

    ehci->working = true;



    t_now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);

    ns_elapsed = t_now - ehci->last_run_ns;

    uframes = ns_elapsed / UFRAME_TIMER_NS;
@@ -2322,6 +2327,8 @@ static void ehci_work_bh(void *opaque) 
        }

        timer_mod(ehci->frame_timer, expire_time);

    }



    ehci->working = false;

}



static void ehci_work_timer(void *opaque)

hw/usb/hcd-ehci.h

+1 −0
Original line number Diff line number Diff line
@@ -297,6 +297,7 @@ struct EHCIState { 
     */

    QEMUTimer *frame_timer;

    QEMUBH *async_bh;

    bool working;

    uint32_t astate;         /* Current state in asynchronous schedule */

    uint32_t pstate;         /* Current state in periodic schedule     */

    USBPort ports[NB_PORTS];