From 0c55671f84fffe591e8435c93a8c83286fd6b8eb Mon Sep 17 00:00:00 2001 From: KarimAllah Ahmed Date: Thu, 31 Jan 2019 21:24:44 +0100 Subject: 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 Signed-off-by: Paolo Bonzini --- arch/x86/kernel/e820.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index 2879e234e193..76dd605ee2a3 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -73,12 +73,13 @@ EXPORT_SYMBOL(pci_mem_start); * This function checks if any part of the range is mapped * with type. */ -bool e820__mapped_any(u64 start, u64 end, enum e820_type type) +static bool _e820__mapped_any(struct e820_table *table, + u64 start, u64 end, enum e820_type type) { int i; - for (i = 0; i < e820_table->nr_entries; i++) { - struct e820_entry *entry = &e820_table->entries[i]; + for (i = 0; i < table->nr_entries; i++) { + struct e820_entry *entry = &table->entries[i]; if (type && entry->type != type) continue; @@ -88,6 +89,17 @@ bool e820__mapped_any(u64 start, u64 end, enum e820_type type) } return 0; } + +bool e820__mapped_raw_any(u64 start, u64 end, enum e820_type type) +{ + return _e820__mapped_any(e820_table_firmware, start, end, type); +} +EXPORT_SYMBOL_GPL(e820__mapped_raw_any); + +bool e820__mapped_any(u64 start, u64 end, enum e820_type type) +{ + return _e820__mapped_any(e820_table, start, end, type); +} EXPORT_SYMBOL_GPL(e820__mapped_any); /* -- cgit v1.2.3