| Message ID | 1451277767-9325-1-git-send-email-caoj.fnst@cn.fujitsu.com |
|---|---|
| State | New |
| Headers | show |
CC the code author: Tiejun Chen <tiejun.chen@intel.com> On 12/28/2015 12:42 PM, Cao jin wrote: > Fix the bug introduced by 595a4f07: Function host_pci_config_read() should be > passed by a reference, not a value, for the later pci_default_write_config(). > And because value in PCI config space are little-endian, use cpu_to_le32() to > ensure it when write config. > > Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com> > --- > Separated from previous "igd-passthru convert to realize" patch. Since these > two don`t have dependency, can send it solely. > > Not test since it is easy to find out if reading carefully, just compiled. > > hw/pci-host/piix.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c > index 715208b..a9cb983 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); > } while (rc < 0 && (errno == EINTR || errno == EAGAIN)); > if (rc != len) { > ret = -errno; > } > + > out: > close(config_fd); > return ret; > @@ -805,11 +807,11 @@ static int igd_pt_i440fx_initfn(struct PCIDevice *pci_dev) > for (i = 0; i < num; i++) { > pos = igd_host_bridge_infos[i].offset; > len = igd_host_bridge_infos[i].len; > - rc = host_pci_config_read(pos, len, val); > + rc = host_pci_config_read(pos, len, &val); > if (rc) { > return -ENODEV; > } > - pci_default_write_config(pci_dev, pos, val, len); > + pci_default_write_config(pci_dev, pos, cpu_to_le32(val), len); > } > > return 0; >
Oops, got following feedback 2nd time: The following message to <tiejun.chen@intel.com> was undeliverable. The reason for the problem: 5.1.0 - Unknown address error 550-'#5.1.0 Address rejected.' I guess the author address is not available anymore On 12/29/2015 07:54 PM, Cao jin wrote: > CC the code author: Tiejun Chen <tiejun.chen@intel.com> > > On 12/28/2015 12:42 PM, Cao jin wrote: >> Fix the bug introduced by 595a4f07: Function host_pci_config_read() >> should be >> passed by a reference, not a value, for the later >> pci_default_write_config(). >> And because value in PCI config space are little-endian, use >> cpu_to_le32() to >> ensure it when write config. >> >> Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com> >> --- >> Separated from previous "igd-passthru convert to realize" patch. Since >> these >> two don`t have dependency, can send it solely. >> >> Not test since it is easy to find out if reading carefully, just >> compiled. >> >> hw/pci-host/piix.c | 10 ++++++---- >> 1 file changed, 6 insertions(+), 4 deletions(-) >> >> diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c >> index 715208b..a9cb983 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); >> } while (rc < 0 && (errno == EINTR || errno == EAGAIN)); >> if (rc != len) { >> ret = -errno; >> } >> + >> out: >> close(config_fd); >> return ret; >> @@ -805,11 +807,11 @@ static int igd_pt_i440fx_initfn(struct PCIDevice >> *pci_dev) >> for (i = 0; i < num; i++) { >> pos = igd_host_bridge_infos[i].offset; >> len = igd_host_bridge_infos[i].len; >> - rc = host_pci_config_read(pos, len, val); >> + rc = host_pci_config_read(pos, len, &val); >> if (rc) { >> return -ENODEV; >> } >> - pci_default_write_config(pci_dev, pos, val, len); >> + pci_default_write_config(pci_dev, pos, cpu_to_le32(val), len); >> } >> >> return 0; >> >
>>> Separated from previous "igd-passthru convert to realize" patch. Since >>> these two don`t have dependency, can send it solely. >>> >>> Not test since it is easy to find out if reading carefully, just >>> compiled. This patch works but the added conversion to LE is conceptually wrong. The conversion from LE to CPU and vice versa is already done by host_pci_config_read and pci_default_write_config. You don't have it in host_pci_config_read because the code is not portable and x86 is little-endian. Generally, functions that accept/return integers take care themselves of endianness conversions. Paolo >>> hw/pci-host/piix.c | 10 ++++++---- >>> 1 file changed, 6 insertions(+), 4 deletions(-) >>> >>> diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c >>> index 715208b..a9cb983 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); >>> } while (rc < 0 && (errno == EINTR || errno == EAGAIN)); >>> if (rc != len) { >>> ret = -errno; >>> } >>> + >>> out: >>> close(config_fd); >>> return ret; >>> @@ -805,11 +807,11 @@ static int igd_pt_i440fx_initfn(struct PCIDevice >>> *pci_dev) >>> for (i = 0; i < num; i++) { >>> pos = igd_host_bridge_infos[i].offset; >>> len = igd_host_bridge_infos[i].len; >>> - rc = host_pci_config_read(pos, len, val); >>> + rc = host_pci_config_read(pos, len, &val); >>> if (rc) { >>> return -ENODEV; >>> } >>> - pci_default_write_config(pci_dev, pos, val, len); >>> + pci_default_write_config(pci_dev, pos, cpu_to_le32(val), len); >>> } >>> >>> return 0; >>> >> >
Hi Paolo On 12/30/2015 12:25 AM, Paolo Bonzini wrote: >>>> Separated from previous "igd-passthru convert to realize" patch. Since >>>> these two don`t have dependency, can send it solely. >>>> >>>> Not test since it is easy to find out if reading carefully, just >>>> compiled. > > This patch works but the added conversion to LE is conceptually wrong. > The conversion from LE to CPU and vice versa is already done by > host_pci_config_read and pci_default_write_config. You don't have it in > host_pci_config_read because the code is not portable and x86 is > little-endian. > Do you mean, this code section(or this igd passthru device)will only run on x86? If it is, yes, the cpu_to_le32() is not necessary. If it has opportunity to run on BE, I think it is necessary, right? The reason I add the conversion is that I am not sure whether it will run on a BE machine or not, and it will no bad to LE machine like x86. > Generally, functions that accept/return integers take care themselves of > endianness conversions. > > Paolo > > >>>> hw/pci-host/piix.c | 10 ++++++---- >>>> 1 file changed, 6 insertions(+), 4 deletions(-) >>>> >>>> diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c >>>> index 715208b..a9cb983 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); >>>> } while (rc < 0 && (errno == EINTR || errno == EAGAIN)); >>>> if (rc != len) { >>>> ret = -errno; >>>> } >>>> + >>>> out: >>>> close(config_fd); >>>> return ret; >>>> @@ -805,11 +807,11 @@ static int igd_pt_i440fx_initfn(struct PCIDevice >>>> *pci_dev) >>>> for (i = 0; i < num; i++) { >>>> pos = igd_host_bridge_infos[i].offset; >>>> len = igd_host_bridge_infos[i].len; >>>> - rc = host_pci_config_read(pos, len, val); >>>> + rc = host_pci_config_read(pos, len, &val); >>>> if (rc) { >>>> return -ENODEV; >>>> } >>>> - pci_default_write_config(pci_dev, pos, val, len); >>>> + pci_default_write_config(pci_dev, pos, cpu_to_le32(val), len); >>>> } >>>> >>>> return 0; >>>> >>> >> > > > . >
diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c index 715208b..a9cb983 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); } while (rc < 0 && (errno == EINTR || errno == EAGAIN)); if (rc != len) { ret = -errno; } + out: close(config_fd); return ret; @@ -805,11 +807,11 @@ static int igd_pt_i440fx_initfn(struct PCIDevice *pci_dev) for (i = 0; i < num; i++) { pos = igd_host_bridge_infos[i].offset; len = igd_host_bridge_infos[i].len; - rc = host_pci_config_read(pos, len, val); + rc = host_pci_config_read(pos, len, &val); if (rc) { return -ENODEV; } - pci_default_write_config(pci_dev, pos, val, len); + pci_default_write_config(pci_dev, pos, cpu_to_le32(val), len); } return 0;
Fix the bug introduced by 595a4f07: Function host_pci_config_read() should be passed by a reference, not a value, for the later pci_default_write_config(). And because value in PCI config space are little-endian, use cpu_to_le32() to ensure it when write config. Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com> --- Separated from previous "igd-passthru convert to realize" patch. Since these two don`t have dependency, can send it solely. Not test since it is easy to find out if reading carefully, just compiled. hw/pci-host/piix.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)