Hi, Am 18.07.2013 17:27, schrieb Mike Qiu: > Hi all > > Any comments ?
You should've CCed the USB maintainer whose file you are touching for review rather than just ppc people, see ./MAINTAINERS. There's some typos in the commit message, but the change looks okay to me - although there were discussions to catch this on the memory API side of things instead. Regards, Andreas > > Thanks > Mike > 2013/7/16 11:50, Mike Qiu wrote: >> For usb-ehci in qemu, its caps just has read() operation, >> the write() operation does not exist. >> >> This cause a Segmentation fault when use usb-ehci device in ppc64 >> platform. >> >> here is gdb output: >> >> Program received signal SIGSEGV, Segmentation fault. >> [Switching to Thread 0x3fffa7fcef20 (LWP 6793)] >> 0x00000000103f5244 in memory_region_oldmmio_write_accessor >> (opaque=0x113e9e78, addr=9, value=0x3fffa7fce088, >> size=1, shift=0, mask=255) at /home/Mike/qemu-impreza/memory.c:384 >> 384 mr->ops->old_mmio.write[ctz32(size)](mr->opaque, addr, tmp); >> (gdb) p *mr->ops >> $1 = {read = @0x10716f68: 0x1020699c <ehci_caps_read>, write = 0, >> endianness = DEVICE_LITTLE_ENDIAN, valid = {min_access_size = 1, >> max_access_size = 4, unaligned = false, accepts = 0}, impl = >> {min_access_size = 1, max_access_size = 1, unaligned = false}, >> old_mmio = {read = {0, 0, 0}, write = {0, 0, 0}}} >> >> Becasue function write() of mr->ops has not been implement, in >> function memory_region_dispatch_write(), it call >> oldmmio write accessor, but at the same time old_mmio still not >> been implement by default. >> >> That is the root cause of the Segmentation fault. >> >> To solve this problem, add empty function: ehci_caps_write() >> >> Signed-off-by: Mike Qiu <qiud...@linux.vnet.ibm.com> >> --- >> hw/usb/hcd-ehci.c | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c >> index 67e4b24..6c8a439 100644 >> --- a/hw/usb/hcd-ehci.c >> +++ b/hw/usb/hcd-ehci.c >> @@ -1072,6 +1072,12 @@ static void ehci_port_write(void *ptr, hwaddr addr, >> trace_usb_ehci_portsc_change(addr + s->portscbase, addr >> 2, *portsc, >> old); >> } >> >> +static void ehci_caps_write(void *ptr, hwaddr addr, uint64_t val, >> + unsigned size) >> +{ >> + /* nothing */ >> +} >> + >> static void ehci_opreg_write(void *ptr, hwaddr addr, >> uint64_t val, unsigned size) >> { >> @@ -2380,6 +2386,7 @@ static void ehci_frame_timer(void *opaque) >> >> static const MemoryRegionOps ehci_mmio_caps_ops = { >> .read = ehci_caps_read, >> + .write = ehci_caps_write, >> .valid.min_access_size = 1, >> .valid.max_access_size = 4, >> .impl.min_access_size = 1, > > -- SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer; HRB 16746 AG Nürnberg