On 02/01/2016 10:06, Stefan Weil wrote: > Am 02.01.2016 um 09:02 schrieb Cao jin: >> Fix the bug introduced by 595a4f07: function host_pci_config_read() should be >> pass-by-reference, not value. >> >> Signed-off-by: Cao jin <caoj.f...@cn.fujitsu.com> >> --- >> v3 changelog: >> 1. Remove cpu_to_le32() since the code only runs on X86. >> >> hw/pci-host/piix.c | 8 +++++--- >> 1 file changed, 5 insertions(+), 3 deletions(-) >> >> diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c >> index 715208b..924f0fa 100644 >> --- a/hw/pci-host/piix.c >> +++ b/hw/pci-host/piix.c >> @@ -761,7 +761,7 @@ static const IGDHostInfo igd_host_bridge_infos[] = { >> {0xa8, 4}, /* SNB: base of GTT stolen memory */ >> }; >> >> -static int host_pci_config_read(int pos, int len, uint32_t val) >> +static int host_pci_config_read(int pos, int len, uint32_t *val) >> { >> char path[PATH_MAX]; >> int config_fd; >> @@ -784,12 +784,14 @@ static int host_pci_config_read(int pos, int len, >> uint32_t val) >> ret = -errno; >> goto out; >> } >> + >> do { >> - rc = read(config_fd, (uint8_t *)&val, len); >> + rc = read(config_fd, (uint8_t *)val, len); > > The type cast is not needed here, because read accepts any pointer > type for the buffer argument. > > While looking at that code, I noticed more potential issues: > > * The open statement needs O_RDWR | O_BINARY, otherwise the code won't > work on Windows. > > * The len argument can obviously be 2 or 4. Will endianness handling > work for both cases?
Not sure why this is in pci-host/piix.c, but it's only used on Intel processors and only on Linux. Paolo