Regression by 01f779f4862b ("irqchip/GIC: Don't deactivate interrupts forwarded to a guest")

[jszhang@marvell.com (Jisheng Zhang)]

Hi Marc,

Commit 01f779f4862b ("irqchip/GIC: Don't deactivate interrupts forwarded to a
guest") causes a regression on Marvell BG4CT SoC. In this SoC, there's only one
GIC, the secondary irq controller is Synopsys DW iCtl:
drivers/irqchip/irq-dw-apb-ictl.c

So cascading_gic_irq() should return true on Marvell BG4CT SoC, but it returns
false. The logic in cascading_gic_irq() doesn't take cascaded irq controller
which is provided by non-gic controllers.

bisect log is as following:

git bisect start
# bad: [865ca084fdc68cd9b658da4b098008278da8fed3] ia64: Enable userfaultfd and membarrier system calls
git bisect bad 865ca084fdc68cd9b658da4b098008278da8fed3
# good: [f377ea88b862bf7151be96d276f4cb740f8e1c41] Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
git bisect good f377ea88b862bf7151be96d276f4cb740f8e1c41
# bad: [3af6e98f25d1f68b9c36beee330342944a4e0048] Merge tag 'platform-drivers-x86-v4.3-1' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86
git bisect bad 3af6e98f25d1f68b9c36beee330342944a4e0048
# good: [bd779669945ed9982890da789ad32e3bd0d41f14] Merge tag 'for-linus-4.3-merge-window-part-1' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs
git bisect good bd779669945ed9982890da789ad32e3bd0d41f14
# bad: [6f0a2fc1feb19bd142961a39dc118e7e55418b3f] Merge branch 'nmi' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
git bisect bad 6f0a2fc1feb19bd142961a39dc118e7e55418b3f
# good: [77a78806c7df8d414c33031a1ca5121876910c4f] Merge tag 'xfs-for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
git bisect good 77a78806c7df8d414c33031a1ca5121876910c4f
# good: [0762ed2ced40bfe648378ef0e1635cf4d3a6fb76] NFSv4.1/flexfiles: Allow coalescing of new layout segments and existing ones
git bisect good 0762ed2ced40bfe648378ef0e1635cf4d3a6fb76
# good: [0762ed2ced40bfe648378ef0e1635cf4d3a6fb76] NFSv4.1/flexfiles: Allow coalescing of new layout segments and existing ones
git bisect good 0762ed2ced40bfe648378ef0e1635cf4d3a6fb76
# good: [1c8cc72d57f321bfccadf4f7b38b94ba287928bc] Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
git bisect good 1c8cc72d57f321bfccadf4f7b38b94ba287928bc
# good: [a11f4f0a4e18b4bdc7d5e36438711e038b7a1f74] xen: xensyms support
git bisect good a11f4f0a4e18b4bdc7d5e36438711e038b7a1f74
# good: [626d7508664c4bc8e67f496da4387ecd0c410b8c] xen: switch extra memory accounting to use pfns
git bisect good 626d7508664c4bc8e67f496da4387ecd0c410b8c
# bad: [4a6ac3044f1504fe4521efa7334095c9c9ceecfd] irqchip/GIC: Fix EOImode setting for non-DT/ACPI systems
git bisect bad 4a6ac3044f1504fe4521efa7334095c9c9ceecfd
# good: [530bf353e4eb06bcba5078390c949650cd26a7c7] irqchip/GICv3: Don't deactivate interrupts forwarded to a guest
git bisect good 530bf353e4eb06bcba5078390c949650cd26a7c7
# bad: [01f779f4862b53810ba4eb247f57bd1ad31d1c18] irqchip/GIC: Don't deactivate interrupts forwarded to a guest
git bisect bad 01f779f4862b53810ba4eb247f57bd1ad31d1c18
# good: [0b996fd35957a30568cddbce05b917c1897966e0] irqchip/GIC: Convert to EOImode == 1
git bisect good 0b996fd35957a30568cddbce05b917c1897966e0
# first bad commit: [01f779f4862b53810ba4eb247f57bd1ad31d1c18] irqchip/GIC: Don't deactivate interrupts forwarded to a guest

Thanks,
Jisheng