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| author |   Igor Mammedov <imammedo@redhat.com> | 2015-12-04 14:07:06 +0100 |
|---|---|---|
| committer |   Ingo Molnar <mingo@kernel.org> | 2015-12-06 12:46:31 +0100 |
| commit | ec941c5ffede4d788b9fc008f9eeca75b9e964f5 (patch) | |
| tree | 619327282c986b220203dbc356b9e5d3df54f9c9 /arch/x86/kernel/pci-swiotlb.c | |
| parent | x86/mm: Introduce max_possible_pfn (diff) | |
| download | wireguard-linux-ec941c5ffede4d788b9fc008f9eeca75b9e964f5.tar.xz wireguard-linux-ec941c5ffede4d788b9fc008f9eeca75b9e964f5.zip | |
x86/mm/64: Enable SWIOTLB if system has SRAT memory regions above MAX_DMA32_PFN
when memory hotplug enabled system is booted with less
than 4GB of RAM and then later more RAM is hotplugged
32-bit devices stop functioning with following error:
nommu_map_single: overflow 327b4f8c0+1522 of device mask ffffffff
the reason for this is that if x86_64 system were booted
with RAM less than 4GB, it doesn't enable SWIOTLB and
when memory is hotplugged beyond MAX_DMA32_PFN, devices
that expect 32-bit addresses can't handle 64-bit addresses.
Fix it by tracking max possible PFN when parsing
memory affinity structures from SRAT ACPI table and
enable SWIOTLB if there is hotpluggable memory
regions beyond MAX_DMA32_PFN.
It fixes KVM guests when they use emulated devices
(reproduces with ata_piix, e1000 and usb devices,
RHBZ: 1275941, 1275977, 1271527)
It also fixes the HyperV, VMWare with emulated devices
which are affected by this issue as well.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akataria@vmware.com
Cc: fujita.tomonori@lab.ntt.co.jp
Cc: konrad.wilk@oracle.com
Cc: pbonzini@redhat.com
Cc: revers@redhat.com
Cc: riel@redhat.com
Link: http://lkml.kernel.org/r/1449234426-273049-3-git-send-email-imammedo@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/pci-swiotlb.c')
| -rw-r--r-- | arch/x86/kernel/pci-swiotlb.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c index adf0392d549a..7c577a178859 100644 --- a/arch/x86/kernel/pci-swiotlb.c +++ b/arch/x86/kernel/pci-swiotlb.c @@ -88,7 +88,7 @@ int __init pci_swiotlb_detect_4gb(void) { /* don't initialize swiotlb if iommu=off (no_iommu=1) */ #ifdef CONFIG_X86_64 - if (!no_iommu && max_pfn > MAX_DMA32_PFN) + if (!no_iommu && max_possible_pfn > MAX_DMA32_PFN) swiotlb = 1; #endif return swiotlb; |