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0a3a58de31
The Xen MSI → PIRQ magic does support MSI-X, so advertise it. (In fact it's better off with MSI-X than MSI, because it's actually broken by design for 32-bit MSI, since it puts the high bits of the PIRQ# into the high 32 bits of the MSI message address, instead of the Extended Destination ID field which is in bits 4-11. Strictly speaking, this really fixes a much older commit2e4386eba0("x86/xen: Wrap XEN MSI management into irqdomain") which failed to set the flag. But that never really mattered until __pci_enable_msix_range() started to check and bail out early. So in 6.2-rc we see failures e.g. to bring up networking on an Amazon EC2 m4.16xlarge instance: [ 41.498694] ena 0000:00:03.0 (unnamed net_device) (uninitialized): Failed to enable MSI-X. irq_cnt -524 [ 41.498705] ena 0000:00:03.0: Can not reserve msix vectors [ 41.498712] ena 0000:00:03.0: Failed to enable and set the admin interrupts Side note: This is the first bug found, and first patch tested, by running Xen guests under QEMU/KVM instead of running under actual Xen. Fixes:99f3d27976("PCI/MSI: Reject MSI-X early") Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/4bffa69a949bfdc92c4a18e5a1c3cbb3b94a0d32.camel@infradead.org
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.