| Message ID | 1398954948-24219-1-git-send-email-marcel.a@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Thu, May 01, 2014 at 05:35:48PM +0300, Marcel Apfelbaum wrote: > When a board is added, the shpchp driver checks if there > is a mismatch between the bridge's adapter and the bus speed. > If there is, it sets the subordinate speed (if there is no device on it). > > However, it takes the reference of the board speed from the primary bus > and not from the subordinate. If the primary bus is PCI and not PCIX/PCIe, > its speed is not updated and remains 0xff. As a result hotplug fails > with error: "Speed of bus ff and adapter 0 mismatch". > > Fixed that by checking the speed against the subordinate bus. > > Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com> > Acked-by: Michael S. Tsirkin <mst@redhat.com> Looking at git history, I suspect this is a regression introduced by commit 3749c51ac6c1560aa1cb1520066bed84c6f8152a Author: Matthew Wilcox <matthew@wil.cx> Date: Sun Dec 13 08:11:32 2009 -0500 PCI: Make current and maximum bus speeds part of the PCI core At least I remember this configuration worked for me early in 2009... > --- > drivers/pci/hotplug/shpchp_ctrl.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/hotplug/shpchp_ctrl.c b/drivers/pci/hotplug/shpchp_ctrl.c > index 5849927..6efc2ec 100644 > --- a/drivers/pci/hotplug/shpchp_ctrl.c > +++ b/drivers/pci/hotplug/shpchp_ctrl.c > @@ -282,8 +282,8 @@ static int board_added(struct slot *p_slot) > return WRONG_BUS_FREQUENCY; > } > > - bsp = ctrl->pci_dev->bus->cur_bus_speed; > - msp = ctrl->pci_dev->bus->max_bus_speed; > + bsp = ctrl->pci_dev->subordinate->cur_bus_speed; > + msp = ctrl->pci_dev->subordinate->max_bus_speed; > > /* Check if there are other slots or devices on the same bus */ > if (!list_empty(&ctrl->pci_dev->subordinate->devices)) > -- > 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, May 1, 2014 at 8:35 AM, Marcel Apfelbaum <marcel.a@redhat.com> wrote: > When a board is added, the shpchp driver checks if there > is a mismatch between the bridge's adapter and the bus speed. > If there is, it sets the subordinate speed (if there is no device on it). > > However, it takes the reference of the board speed from the primary bus > and not from the subordinate. If the primary bus is PCI and not PCIX/PCIe, > its speed is not updated and remains 0xff. As a result hotplug fails > with error: "Speed of bus ff and adapter 0 mismatch". It'd be cool to have a bugzilla for this with lspci and dmesg output. I'll also have to check the other hotplug drivers for similar issues, unless you've already done that. > Fixed that by checking the speed against the subordinate bus. > > Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com> > Acked-by: Michael S. Tsirkin <mst@redhat.com> > --- > drivers/pci/hotplug/shpchp_ctrl.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/hotplug/shpchp_ctrl.c b/drivers/pci/hotplug/shpchp_ctrl.c > index 5849927..6efc2ec 100644 > --- a/drivers/pci/hotplug/shpchp_ctrl.c > +++ b/drivers/pci/hotplug/shpchp_ctrl.c > @@ -282,8 +282,8 @@ static int board_added(struct slot *p_slot) > return WRONG_BUS_FREQUENCY; > } > > - bsp = ctrl->pci_dev->bus->cur_bus_speed; > - msp = ctrl->pci_dev->bus->max_bus_speed; > + bsp = ctrl->pci_dev->subordinate->cur_bus_speed; > + msp = ctrl->pci_dev->subordinate->max_bus_speed; > > /* Check if there are other slots or devices on the same bus */ > if (!list_empty(&ctrl->pci_dev->subordinate->devices)) > -- > 1.8.3.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, 2014-05-01 at 12:02 -0600, Bjorn Helgaas wrote: > On Thu, May 1, 2014 at 8:35 AM, Marcel Apfelbaum <marcel.a@redhat.com> wrote: > > When a board is added, the shpchp driver checks if there > > is a mismatch between the bridge's adapter and the bus speed. > > If there is, it sets the subordinate speed (if there is no device on it). > > > > However, it takes the reference of the board speed from the primary bus > > and not from the subordinate. If the primary bus is PCI and not PCIX/PCIe, > > its speed is not updated and remains 0xff. As a result hotplug fails > > with error: "Speed of bus ff and adapter 0 mismatch". > > It'd be cool to have a bugzilla for this with lspci and dmesg output. > I'll also have to check the other hotplug drivers for similar issues, > unless you've already done that. I'll open a BZ with the details, sure. I didn't check the other hotplug drivers, but I do plan to look into PCIe driver as part of QEMU's PCIe hotplug feature. Thanks, Marcel > > > Fixed that by checking the speed against the subordinate bus. > > > > Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com> > > Acked-by: Michael S. Tsirkin <mst@redhat.com> > > --- > > drivers/pci/hotplug/shpchp_ctrl.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/pci/hotplug/shpchp_ctrl.c b/drivers/pci/hotplug/shpchp_ctrl.c > > index 5849927..6efc2ec 100644 > > --- a/drivers/pci/hotplug/shpchp_ctrl.c > > +++ b/drivers/pci/hotplug/shpchp_ctrl.c > > @@ -282,8 +282,8 @@ static int board_added(struct slot *p_slot) > > return WRONG_BUS_FREQUENCY; > > } > > > > - bsp = ctrl->pci_dev->bus->cur_bus_speed; > > - msp = ctrl->pci_dev->bus->max_bus_speed; > > + bsp = ctrl->pci_dev->subordinate->cur_bus_speed; > > + msp = ctrl->pci_dev->subordinate->max_bus_speed; > > > > /* Check if there are other slots or devices on the same bus */ > > if (!list_empty(&ctrl->pci_dev->subordinate->devices)) > > -- > > 1.8.3.1 > > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, 2014-05-01 at 21:13 +0300, Marcel Apfelbaum wrote: > On Thu, 2014-05-01 at 12:02 -0600, Bjorn Helgaas wrote: > > On Thu, May 1, 2014 at 8:35 AM, Marcel Apfelbaum <marcel.a@redhat.com> wrote: > > > When a board is added, the shpchp driver checks if there > > > is a mismatch between the bridge's adapter and the bus speed. > > > If there is, it sets the subordinate speed (if there is no device on it). > > > > > > However, it takes the reference of the board speed from the primary bus > > > and not from the subordinate. If the primary bus is PCI and not PCIX/PCIe, > > > its speed is not updated and remains 0xff. As a result hotplug fails > > > with error: "Speed of bus ff and adapter 0 mismatch". > > > > It'd be cool to have a bugzilla for this with lspci and dmesg output. > > I'll also have to check the other hotplug drivers for similar issues, > > unless you've already done that. > I'll open a BZ with the details, sure. Done: https://bugzilla.kernel.org/show_bug.cgi?id=75251 If you need further details, please let me know. Thanks, Marcel > > I didn't check the other hotplug drivers, but I do plan > to look into PCIe driver as part of QEMU's PCIe hotplug feature. > > Thanks, > Marcel > > > > > > Fixed that by checking the speed against the subordinate bus. > > > > > > Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com> > > > Acked-by: Michael S. Tsirkin <mst@redhat.com> > > > --- > > > drivers/pci/hotplug/shpchp_ctrl.c | 4 ++-- > > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/pci/hotplug/shpchp_ctrl.c b/drivers/pci/hotplug/shpchp_ctrl.c > > > index 5849927..6efc2ec 100644 > > > --- a/drivers/pci/hotplug/shpchp_ctrl.c > > > +++ b/drivers/pci/hotplug/shpchp_ctrl.c > > > @@ -282,8 +282,8 @@ static int board_added(struct slot *p_slot) > > > return WRONG_BUS_FREQUENCY; > > > } > > > > > > - bsp = ctrl->pci_dev->bus->cur_bus_speed; > > > - msp = ctrl->pci_dev->bus->max_bus_speed; > > > + bsp = ctrl->pci_dev->subordinate->cur_bus_speed; > > > + msp = ctrl->pci_dev->subordinate->max_bus_speed; > > > > > > /* Check if there are other slots or devices on the same bus */ > > > if (!list_empty(&ctrl->pci_dev->subordinate->devices)) > > > -- > > > 1.8.3.1 > > > > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, May 1, 2014 at 12:57 PM, Marcel Apfelbaum <marcel.apfelbaum@gmail.com> wrote: > On Thu, 2014-05-01 at 21:13 +0300, Marcel Apfelbaum wrote: >> On Thu, 2014-05-01 at 12:02 -0600, Bjorn Helgaas wrote: >> > On Thu, May 1, 2014 at 8:35 AM, Marcel Apfelbaum <marcel.a@redhat.com> wrote: >> > > When a board is added, the shpchp driver checks if there >> > > is a mismatch between the bridge's adapter and the bus speed. >> > > If there is, it sets the subordinate speed (if there is no device on it). >> > > >> > > However, it takes the reference of the board speed from the primary bus >> > > and not from the subordinate. If the primary bus is PCI and not PCIX/PCIe, >> > > its speed is not updated and remains 0xff. As a result hotplug fails >> > > with error: "Speed of bus ff and adapter 0 mismatch". >> > >> > It'd be cool to have a bugzilla for this with lspci and dmesg output. >> > I'll also have to check the other hotplug drivers for similar issues, >> > unless you've already done that. >> I'll open a BZ with the details, sure. > Done: https://bugzilla.kernel.org/show_bug.cgi?id=75251 > If you need further details, please let me know. Thanks. Would you mind attaching the "lspci -vv" output? That should show more details, including the information used to compute the bus speed. Also, you checked the "regression" box. Can you confirm that and identify a known-working kernel? If we know which kernels are broken, we can potentially mark the fix to be backported to them. Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, 2014-05-01 at 14:00 -0600, Bjorn Helgaas wrote: > On Thu, May 1, 2014 at 12:57 PM, Marcel Apfelbaum > <marcel.apfelbaum@gmail.com> wrote: > > On Thu, 2014-05-01 at 21:13 +0300, Marcel Apfelbaum wrote: > >> On Thu, 2014-05-01 at 12:02 -0600, Bjorn Helgaas wrote: > >> > On Thu, May 1, 2014 at 8:35 AM, Marcel Apfelbaum <marcel.a@redhat.com> wrote: > >> > > When a board is added, the shpchp driver checks if there > >> > > is a mismatch between the bridge's adapter and the bus speed. > >> > > If there is, it sets the subordinate speed (if there is no device on it). > >> > > > >> > > However, it takes the reference of the board speed from the primary bus > >> > > and not from the subordinate. If the primary bus is PCI and not PCIX/PCIe, > >> > > its speed is not updated and remains 0xff. As a result hotplug fails > >> > > with error: "Speed of bus ff and adapter 0 mismatch". > >> > > >> > It'd be cool to have a bugzilla for this with lspci and dmesg output. > >> > I'll also have to check the other hotplug drivers for similar issues, > >> > unless you've already done that. > >> I'll open a BZ with the details, sure. > > Done: https://bugzilla.kernel.org/show_bug.cgi?id=75251 > > If you need further details, please let me know. > > Thanks. Would you mind attaching the "lspci -vv" output? That should > show more details, including the information used to compute the bus > speed. Sure, done. > > Also, you checked the "regression" box. Can you confirm that and > identify a known-working kernel? If we know which kernels are broken, > we can potentially mark the fix to be backported to them. I checked the regression box based on Michael's comment that in early 2009 it did work. He pointed out a commit he thinks that caused this regression. I think it can be backported to all the relevant stable versions since the commit that introduced the code mentioned in the patch. Thanks, Marcel > > Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, 2014-05-01 at 14:00 -0600, Bjorn Helgaas wrote: > On Thu, May 1, 2014 at 12:57 PM, Marcel Apfelbaum > <marcel.apfelbaum@gmail.com> wrote: > > On Thu, 2014-05-01 at 21:13 +0300, Marcel Apfelbaum wrote: > >> On Thu, 2014-05-01 at 12:02 -0600, Bjorn Helgaas wrote: > >> > On Thu, May 1, 2014 at 8:35 AM, Marcel Apfelbaum <marcel.a@redhat.com> wrote: > >> > > When a board is added, the shpchp driver checks if there > >> > > is a mismatch between the bridge's adapter and the bus speed. > >> > > If there is, it sets the subordinate speed (if there is no device on it). > >> > > > >> > > However, it takes the reference of the board speed from the primary bus > >> > > and not from the subordinate. If the primary bus is PCI and not PCIX/PCIe, > >> > > its speed is not updated and remains 0xff. As a result hotplug fails > >> > > with error: "Speed of bus ff and adapter 0 mismatch". > >> > > >> > It'd be cool to have a bugzilla for this with lspci and dmesg output. > >> > I'll also have to check the other hotplug drivers for similar issues, > >> > unless you've already done that. > >> I'll open a BZ with the details, sure. > > Done: https://bugzilla.kernel.org/show_bug.cgi?id=75251 > > If you need further details, please let me know. > > Thanks. Would you mind attaching the "lspci -vv" output? That should > show more details, including the information used to compute the bus > speed. > > Also, you checked the "regression" box. Can you confirm that and > identify a known-working kernel? If we know which kernels are broken, > we can potentially mark the fix to be backported to them. I checked 2.6.24-26-generic that comes with Ubuntu 8.04 and it works OK. So we have a working version. I hope it helps, Marcel > > Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 05/01/2014 05:35 PM, Marcel Apfelbaum wrote: > When a board is added, the shpchp driver checks if there > is a mismatch between the bridge's adapter and the bus speed. > If there is, it sets the subordinate speed (if there is no device on it). Since the speed is irrelevant when running in a VM, I suggest that you either ignore it altogether, or "normalize" the speed of all the devices/bridges/buses in QEMU in order to avoid any conflicts in the first place. Thanks, Ronen. > > However, it takes the reference of the board speed from the primary bus > and not from the subordinate. If the primary bus is PCI and not PCIX/PCIe, > its speed is not updated and remains 0xff. As a result hotplug fails > with error: "Speed of bus ff and adapter 0 mismatch". > > Fixed that by checking the speed against the subordinate bus. > > Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com> > Acked-by: Michael S. Tsirkin <mst@redhat.com> > --- > drivers/pci/hotplug/shpchp_ctrl.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/hotplug/shpchp_ctrl.c b/drivers/pci/hotplug/shpchp_ctrl.c > index 5849927..6efc2ec 100644 > --- a/drivers/pci/hotplug/shpchp_ctrl.c > +++ b/drivers/pci/hotplug/shpchp_ctrl.c > @@ -282,8 +282,8 @@ static int board_added(struct slot *p_slot) > return WRONG_BUS_FREQUENCY; > } > > - bsp = ctrl->pci_dev->bus->cur_bus_speed; > - msp = ctrl->pci_dev->bus->max_bus_speed; > + bsp = ctrl->pci_dev->subordinate->cur_bus_speed; > + msp = ctrl->pci_dev->subordinate->max_bus_speed; > > /* Check if there are other slots or devices on the same bus */ > if (!list_empty(&ctrl->pci_dev->subordinate->devices)) -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sun, 2014-05-04 at 16:48 +0300, Ronen Hod wrote: > On 05/01/2014 05:35 PM, Marcel Apfelbaum wrote: > > When a board is added, the shpchp driver checks if there > > is a mismatch between the bridge's adapter and the bus speed. > > If there is, it sets the subordinate speed (if there is no device on it). > > Since the speed is irrelevant when running in a VM, I suggest that > you either ignore it altogether, or "normalize" the speed of all the > devices/bridges/buses in QEMU in order to avoid any conflicts > in the first place. Before this patch, this would not help since the primary bus speed is not even set by the kernel. After this patch, normalizing the QEMU device/bus/... speed may help avoiding future conflicts, but we should discuss it in qemu mailing list :). Ignoring emulated/para-virt device's speed when running in a VM it is\ a good question, but I don't know if such a distinction would be feasible. Any thoughts would be appreciated, Thanks, Marcel > > Thanks, Ronen. > > > > > However, it takes the reference of the board speed from the primary bus > > and not from the subordinate. If the primary bus is PCI and not PCIX/PCIe, > > its speed is not updated and remains 0xff. As a result hotplug fails > > with error: "Speed of bus ff and adapter 0 mismatch". > > > > Fixed that by checking the speed against the subordinate bus. > > > > Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com> > > Acked-by: Michael S. Tsirkin <mst@redhat.com> > > --- > > drivers/pci/hotplug/shpchp_ctrl.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/pci/hotplug/shpchp_ctrl.c b/drivers/pci/hotplug/shpchp_ctrl.c > > index 5849927..6efc2ec 100644 > > --- a/drivers/pci/hotplug/shpchp_ctrl.c > > +++ b/drivers/pci/hotplug/shpchp_ctrl.c > > @@ -282,8 +282,8 @@ static int board_added(struct slot *p_slot) > > return WRONG_BUS_FREQUENCY; > > } > > > > - bsp = ctrl->pci_dev->bus->cur_bus_speed; > > - msp = ctrl->pci_dev->bus->max_bus_speed; > > + bsp = ctrl->pci_dev->subordinate->cur_bus_speed; > > + msp = ctrl->pci_dev->subordinate->max_bus_speed; > > > > /* Check if there are other slots or devices on the same bus */ > > if (!list_empty(&ctrl->pci_dev->subordinate->devices)) > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/pci/hotplug/shpchp_ctrl.c b/drivers/pci/hotplug/shpchp_ctrl.c index 5849927..6efc2ec 100644 --- a/drivers/pci/hotplug/shpchp_ctrl.c +++ b/drivers/pci/hotplug/shpchp_ctrl.c @@ -282,8 +282,8 @@ static int board_added(struct slot *p_slot) return WRONG_BUS_FREQUENCY; } - bsp = ctrl->pci_dev->bus->cur_bus_speed; - msp = ctrl->pci_dev->bus->max_bus_speed; + bsp = ctrl->pci_dev->subordinate->cur_bus_speed; + msp = ctrl->pci_dev->subordinate->max_bus_speed; /* Check if there are other slots or devices on the same bus */ if (!list_empty(&ctrl->pci_dev->subordinate->devices))