kvm, x86: Properly check whether a pfn is an MMIO or not

pfn_valid check is not sufficient because it only checks if a page has a struct
page or not, if "mem=" was passed to the kernel some valid pages won't have a
struct page. This means that if guests were assigned valid memory that lies
after the mem= boundary it will be passed uncached to the guest no matter what
the guest caching attributes are for this memory.

Introduce a new function e820__mapped_raw_any which is equivalent to
e820__mapped_any but uses the original e820 unmodified and use it to
identify real *RAM*.

Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
KarimAllah Ahmed
2019-01-31 21:24:44 +01:00
committed by Paolo Bonzini
parent e0bf2665ca
commit 0c55671f84
3 changed files with 20 additions and 4 deletions

View File

@@ -10,6 +10,7 @@ extern struct e820_table *e820_table_firmware;
extern unsigned long pci_mem_start;
extern bool e820__mapped_raw_any(u64 start, u64 end, enum e820_type type);
extern bool e820__mapped_any(u64 start, u64 end, enum e820_type type);
extern bool e820__mapped_all(u64 start, u64 end, enum e820_type type);