On 15/11/16 13:53, Yongji Xie wrote: > Hi Bjorn, > > > Kindly ping. What do you think of the way to fix the bug that resources's > size is changed > > when using resource_alignment. Thanks. Could anyone please comment on this? Thanks! > > > On 2016/10/26 14:53, Yongji Xie wrote: >> This series introduces a way for PCI resource allocator to force >> MMIO BARs not to share PAGE_SIZE. This would make sense to VFIO >> driver. Because current VFIO implementation disallows to mmap >> sub-page(size < PAGE_SIZE) MMIO BARs which may share the same page >> with other BARs for security reasons. Thus, we have to handle mmio >> access to these BARs in QEMU emulation rather than in guest which >> will cause some performance loss. >> >> In our solution, we try to make use of the existing code path of >> resource_alignment kernel parameter and add a macro to set default >> alignment for it. Thus we can define this macro by default on some >> archs which may easily hit the performance issue because of their >> 64K page. >> >> In this series, patch 1,2 fixed bugs of using resource_alignment; >> patch 3 adds a macro to set the default alignment of all MMIO BARs. >> >> Changelog v7: >> - Rebased against v4.9-rc2 >> - Drop two merged patches >> - Rework the patch which fix a bug that resources's size is changed when >> using resource_alignment >> - Add a patch that fix a bug for IOV BARs when using resource_alignment >> >> Changelog v6: >> - Remove the option "noresize@" of resource_alignment >> >> Changelog v5: >> - Rebased against v4.8-rc6 >> - Drop the patch that forbidding disable memory decoding in >> pci_reassigndev_resource_alignment() >> >> Changelog v4: >> - Rebased against v4.8-rc1 >> - Drop one irrelevant patch >> - Drop the patch that adding wildcard to resource_alignment to enforce >> the alignment of all MMIO BARs to be at least PAGE_SIZE >> - Change the format of option "noresize" of resource_alignment >> - Code style improvements >> >> Changelog v3: >> - Ignore enforced alignment to fixed BARs >> - Fix issue that disabling memory decoding when reassigning the alignment >> - Only enable default alignment on PowerNV platform >> >> Changelog v2: >> - Ignore enforced alignment to VF BARs on >> pci_reassigndev_resource_alignment() >> >> Yongji Xie (3): >> PCI: Ignore requested alignment for IOV BARs >> PCI: Restore resource's size if we expand it by using resource_alignment >> PCI: Add a macro to set default alignment for all PCI devices >> >> arch/powerpc/include/asm/pci.h | 4 ++++ >> drivers/pci/pci.c | 6 +++++- >> drivers/pci/setup-bus.c | 19 +++++++++++++++++++ >> include/linux/pci.h | 1 + >> 4 files changed, 29 insertions(+), 1 deletion(-) >> > -- Alexey -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
