| Message ID | 20220218075727.2737623-5-davidgow@google.com (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Brendan Higgins |
| Headers | show |
| Series | kunit,um: Fix kunit.py build --alltests | expand |
On Fri, 2022-02-18 at 15:57 +0800, David Gow wrote: > > Note that, while this does build again, it still segfaults on startup, > so more work remains to be done. That's probably just a lot more stuff getting included somehow? > They are: > - CONFIG_VFIO_PCI: Needs ioport_map/ioport_unmap. > - CONFIG_INFINIBAND_RDMAVT: Needs cpuinfo_x86 and __copy_user_nocache > - CONFIG_BNXT: Failing under UML with -Werror > ERROR:root:../drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c: In function ‘bnxt_ptp_enable’: > ../drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c:400:43: error: array subscript 255 is above array bounds of ‘struct pps_pin[4]’ [-Werror=array-bounds] > 400 | ptp->pps_info.pins[pin_id].event = BNXT_PPS_EVENT_EXTERNAL; > | ~~~~~~~~~~~~~~~~~~^~~~~~~~ > - CONFIG_PATA_CS5535: Needs MSR access (__tracepoint_{read,write}_msr) > - CONFIG_VDPA: Enables CONFIG_DMA_OPS, which is unimplemented. ('dma_ops' is not defined) > > These are all issues which should be investigated properly and the > corresponding options either fixed or disabled under UML. Having this > list of broken options should act as a good to-do list here, and will > allow these issues to be worked on independently, and other tests to > work in the meantime. > I'm not really sure it makes sense to even do anything other than disabling these. It looks like all of them are just exposed by now being able to build PCI drivers on UML. Surely the people writing the driver didn't expect their drivers to run over simulated PCI (which is what the UML PCI support is all about). Now from a PCI driver point of view you can't really tell the difference (and anyway the driver won't be probed), but the issues (at least the build time ones) come from having UML && PCI && X86_64 or UML && PCI && X86_32 because drivers typically depend on X86_64 or X86_32, rather than on "X86 && X86_64" or "X86 && X86_32". In a sense thus, the issue is those drivers don't know that "!X86 && (X86_32 || X86_64)" can happen (with UML). Now you could say that's the driver bug, or you could say that they should just add "depends on !UML" (though that's basically equivalent to adding "depends on X86" and the latter may be preferable in some cases). Or actually in the three patches you have (1-3) it's in the code, but same thing, you can either add && !UML (like you did) or add && X86. Arguably, however, building PCI drivers by default is somewhat questionable in the first place? So maybe you should just add # CONFIG_UML_PCI_OVER_VIRTIO is not set to the broken_on_uml.config since it exposes all these issues, and really is not very useful since you're not going to actually run with any simulated PCI devices anyway, so drivers will not be probed. johannes
On Fri, Feb 18, 2022 at 03:57:27PM +0800, David Gow wrote: > There are a number of Kconfig options which break compilation under UML with > allyesconfig. As kunit_tool's --alltests option is based on allyesconfig and > UML, we need to update the list of broken options to make --alltests build > again. > > Note that, while this does build again, it still segfaults on startup, > so more work remains to be done. > > They are: > - CONFIG_VFIO_PCI: Needs ioport_map/ioport_unmap. > - CONFIG_INFINIBAND_RDMAVT: Needs cpuinfo_x86 and __copy_user_nocache It doesn't make sense to patch qib and then turn this option off, it is required to build qib. Jason
On Fri, Feb 18, 2022 at 8:26 PM Johannes Berg <johannes@sipsolutions.net> wrote: > > On Fri, 2022-02-18 at 15:57 +0800, David Gow wrote: > > > > Note that, while this does build again, it still segfaults on startup, > > so more work remains to be done. > > That's probably just a lot more stuff getting included somehow? > Yeah: it used to work (a couple of years ago), but something has broken it in the meantime. It's just a shame that bisecting things with allyesconfig takes so long... > > They are: > > - CONFIG_VFIO_PCI: Needs ioport_map/ioport_unmap. > > - CONFIG_INFINIBAND_RDMAVT: Needs cpuinfo_x86 and __copy_user_nocache > > - CONFIG_BNXT: Failing under UML with -Werror > > ERROR:root:../drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c: In function ‘bnxt_ptp_enable’: > > ../drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c:400:43: error: array subscript 255 is above array bounds of ‘struct pps_pin[4]’ [-Werror=array-bounds] > > 400 | ptp->pps_info.pins[pin_id].event = BNXT_PPS_EVENT_EXTERNAL; > > | ~~~~~~~~~~~~~~~~~~^~~~~~~~ > > - CONFIG_PATA_CS5535: Needs MSR access (__tracepoint_{read,write}_msr) > > - CONFIG_VDPA: Enables CONFIG_DMA_OPS, which is unimplemented. ('dma_ops' is not defined) > > > > These are all issues which should be investigated properly and the > > corresponding options either fixed or disabled under UML. Having this > > list of broken options should act as a good to-do list here, and will > > allow these issues to be worked on independently, and other tests to > > work in the meantime. > > > > I'm not really sure it makes sense to even do anything other than > disabling these. > > It looks like all of them are just exposed by now being able to build > PCI drivers on UML. Surely the people writing the driver didn't expect > their drivers to run over simulated PCI (which is what the UML PCI > support is all about). > > Now from a PCI driver point of view you can't really tell the difference > (and anyway the driver won't be probed), but the issues (at least the > build time ones) come from having > > UML && PCI && X86_64 > > or > > UML && PCI && X86_32 > > because drivers typically depend on X86_64 or X86_32, rather than on > "X86 && X86_64" or "X86 && X86_32". In a sense thus, the issue is those > drivers don't know that "!X86 && (X86_32 || X86_64)" can happen (with > UML). > > > Now you could say that's the driver bug, or you could say that they > should just add "depends on !UML" (though that's basically equivalent to > adding "depends on X86" and the latter may be preferable in some cases). > > Or actually in the three patches you have (1-3) it's in the code, but > same thing, you can either add && !UML (like you did) or add && X86. > I didn't realise X86 wasn't defined in UML: that's definitely a bit cleaner than !UML in a number of these cases. Not all of those issues are fundamentally solved by "depends on X86", though: there are a few which might be other missing things in UML (maybe the 'dma_ops' issues?), and/or might be the result of -Werror being enabled. > > Arguably, however, building PCI drivers by default is somewhat > questionable in the first place? We do want the ability to build PCI drivers under UML, as it makes running KUnit tests for PCI drivers much simpler and more pleasant. And indeed, it does work for KUnit in general, it's just that some drivers do have the issues mentioned above, so allyesconfig picks up every broken driver. We don't actually build the PCI drivers by default, only if the "--alltests" option is passed, which does include them, as we do have tests which depend on PCI we'd like to run (like the thunderbolt test). > > So maybe you should just add > > # CONFIG_UML_PCI_OVER_VIRTIO is not set > > to the broken_on_uml.config since it exposes all these issues, and > really is not very useful since you're not going to actually run with > any simulated PCI devices anyway, so drivers will not be probed. I did try this as well, and it just got us a different set of issues (there are a bunch of drivers which depend on IOMEM but don't state it -- I'll try to send fixes for those out next week). And we'd lose things like the thunderbolt test if PCI Ultimately, the 'broken_on_uml.config' file is just there to pare back allyesconfig a bit for KUnit's purposes, but we still definitely want as many options (and hence tests) enabled as possible long-term. So I think actual fixes to either the code or Kconfig do make sense. Is 'make ARCH=um allyesconfig' something we actually want to be able to build? If so, no amount of adding things to KUnit's broken_on_uml.config will solve the underlying issues, and we'll need to at least update the Kconfig entries. Cheers, -- David
On Sat, 2022-02-19 at 16:00 +0800, David Gow wrote: > On Fri, Feb 18, 2022 at 8:26 PM Johannes Berg <johannes@sipsolutions.net> wrote: > > > > On Fri, 2022-02-18 at 15:57 +0800, David Gow wrote: > > > > > > Note that, while this does build again, it still segfaults on startup, > > > so more work remains to be done. > > > > That's probably just a lot more stuff getting included somehow? > > > > Yeah: it used to work (a couple of years ago), but something has > broken it in the meantime. It's just a shame that bisecting things > with allyesconfig takes so long... Heh, right. But I guess you could "Kconfig bisect" first, i.e. see what option breaks it? It might not even help to bisect, if it's just some option getting enabled over time. Or perhaps the kernel is just too big for the address space layout if you have allyesconfig? Though that shouldn't be an issue, I think. > I didn't realise X86 wasn't defined in UML: X86 is the architecture, X86_{32,64} is kind of a selection for how you want things to be built, and it's thus required for UML on x86, because UML imports stuff from X86. > that's definitely a bit > cleaner than !UML in a number of these cases. It looks like some (most?) of them don't really work that way though since they're not really platform specific, they just know only about a handful of platforms that they're compatible with. > Not all of those issues are fundamentally solved by "depends on X86", > though: there are a few which might be other missing things in UML > (maybe the 'dma_ops' issues?), and/or might be the result of -Werror > being enabled. Right. > We do want the ability to build PCI drivers under UML, as it makes > running KUnit tests for PCI drivers much simpler and more pleasant. OK, fair point. I'm thinking about this area in general also right now for iwlwifi, and obviously we're probably the only user of the virtual PCI code that lets us connect the driver to a simulated device on UML (but the driver doesn't really know) :-) > And indeed, it does work for KUnit in general, it's just that some > drivers do have the issues mentioned above, so allyesconfig picks up > every broken driver. Right. > We don't actually build the PCI drivers by default, only if the > "--alltests" option is passed, which does include them, as we do have > tests which depend on PCI we'd like to run (like the thunderbolt > test). Makes sense. > > I did try this as well, and it just got us a different set of issues > (there are a bunch of drivers which depend on IOMEM but don't state it > -- I'll try to send fixes for those out next week). > Fun. > Ultimately, the 'broken_on_uml.config' file is just there to pare back > allyesconfig a bit for KUnit's purposes, but we still definitely want > as many options (and hence tests) enabled as possible long-term. So I > think actual fixes to either the code or Kconfig do make sense. Makes sense. > Is 'make ARCH=um allyesconfig' something we actually want to be able > to build? If so, no amount of adding things to KUnit's > broken_on_uml.config will solve the underlying issues, and we'll need > to at least update the Kconfig entries. > That's a good point, as long as people are doing allyes/randconfig builds on UML, we probably need to have these fixes anyway rather than disabling something for KUnit specifically. johannes
diff --git a/tools/testing/kunit/configs/broken_on_uml.config b/tools/testing/kunit/configs/broken_on_uml.config index 690870043ac0..546482b0bc4d 100644 --- a/tools/testing/kunit/configs/broken_on_uml.config +++ b/tools/testing/kunit/configs/broken_on_uml.config @@ -42,3 +42,8 @@ # CONFIG_ADI_AXI_ADC is not set # CONFIG_DEBUG_PAGEALLOC is not set # CONFIG_PAGE_POISONING is not set +# CONFIG_VFIO_PCI is not set +# CONFIG_INFINIBAND_RDMAVT is not set +# CONFIG_BNXT is not set +# CONFIG_PATA_CS5535 is not set +# CONFIG_VDPA is not set
There are a number of Kconfig options which break compilation under UML with allyesconfig. As kunit_tool's --alltests option is based on allyesconfig and UML, we need to update the list of broken options to make --alltests build again. Note that, while this does build again, it still segfaults on startup, so more work remains to be done. They are: - CONFIG_VFIO_PCI: Needs ioport_map/ioport_unmap. - CONFIG_INFINIBAND_RDMAVT: Needs cpuinfo_x86 and __copy_user_nocache - CONFIG_BNXT: Failing under UML with -Werror ERROR:root:../drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c: In function ‘bnxt_ptp_enable’: ../drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c:400:43: error: array subscript 255 is above array bounds of ‘struct pps_pin[4]’ [-Werror=array-bounds] 400 | ptp->pps_info.pins[pin_id].event = BNXT_PPS_EVENT_EXTERNAL; | ~~~~~~~~~~~~~~~~~~^~~~~~~~ - CONFIG_PATA_CS5535: Needs MSR access (__tracepoint_{read,write}_msr) - CONFIG_VDPA: Enables CONFIG_DMA_OPS, which is unimplemented. ('dma_ops' is not defined) These are all issues which should be investigated properly and the corresponding options either fixed or disabled under UML. Having this list of broken options should act as a good to-do list here, and will allow these issues to be worked on independently, and other tests to work in the meantime. Signed-off-by: David Gow <davidgow@google.com> --- tools/testing/kunit/configs/broken_on_uml.config | 5 +++++ 1 file changed, 5 insertions(+)