mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-04 14:06:43 +07:00
9f8daccaa0
increasing number of PCI slots in large multi-node systems. The kernel currently attempts by default to allocate memory for all PCI expansion ROMs so there has also been an increasing number of PCI memory allocation failures seen on these systems. This occurs because the BIOS either (1) provides insufficient PCI memory resource for all the expansion ROMs or (2) provides adequate PCI memory resource for expansion ROMs but provides the space in kernel unexpected BIOS assigned P2P non-prefetch windows. The resulting PCI memory allocation failures may be benign when related to memory requests for expansion ROMs themselves but in some cases they can occur when attempting to allocate space for more critical BARs. This can happen when a successful expansion ROM allocation request consumes memory resource that was intended for a non-ROM BAR. We have seen this happen during PCI hotplug of an adapter that contains a P2P bridge where successful memory allocation for an expansion ROM BAR on device behind the bridge consumed memory that was intended for a non-ROM BAR on the P2P bridge. In all cases the allocation failure messages can be very confusing for users. This patch addresses the issue by changing the kernel default behavior so that expansion ROM memory allocations are no longer attempted by default when the BIOS has not assigned a specific address range to the expansion ROM BAR. This was done by changing the 'pci=rom' boot option behavior for BIOS unassigned expansion ROMs to actually match it's current kernel-parameters.txt description which already implies "off" by default. Behavior for BIOS assigned expansion ROMs implemented in pcibios_assign_resources() [arch/x86/pci/i386.c] is unchanged. Signed-off-by: Gary Hade <garyhade@us.ibm.com> Cc: Greg KH <greg@kroah.com> Cc: Jan Beulich <jbeulich@novell.com> Acked-by: "Jun'ichi Nomura" <j-nomura@ce.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
||
|---|---|---|
| .. | ||
| alpha | ||
| arm | ||
| avr32 | ||
| blackfin | ||
| cris | ||
| frv | ||
| h8300 | ||
| ia64 | ||
| m32r | ||
| m68k | ||
| m68knommu | ||
| mips | ||
| parisc | ||
| powerpc | ||
| ppc | ||
| s390 | ||
| sh | ||
| sparc | ||
| sparc64 | ||
| um | ||
| v850 | ||
| x86 | ||
| xtensa | ||
| .gitignore | ||