[PATCH 3.11 018/272] arm/arm64: KVM: Fix hyp mappings of vmalloc regions

From: Luis Henriques
Date: Fri Dec 06 2013 - 09:20:54 EST


3.11.10.1 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Christoffer Dall <christoffer.dall@xxxxxxxxxx>

commit 40c2729bab48e2832b17c1fa8af9db60e776131b upstream.

Using virt_to_phys on percpu mappings is horribly wrong as it may be
backed by vmalloc. Introduce kvm_kaddr_to_phys which translates both
types of valid kernel addresses to the corresponding physical address.

At the same time resolves a typing issue where we were storing the
physical address as a 32 bit unsigned long (on arm), truncating the
physical address for addresses above the 4GB limit. This caused
breakage on Keystone.

Reported-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
Tested-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx>
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
arch/arm/kvm/mmu.c | 34 ++++++++++++++++++++++++++++------
1 file changed, 28 insertions(+), 6 deletions(-)

diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 0988d9e..b91a68b 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -307,6 +307,17 @@ out:
return err;
}

+static phys_addr_t kvm_kaddr_to_phys(void *kaddr)
+{
+ if (!is_vmalloc_addr(kaddr)) {
+ BUG_ON(!virt_addr_valid(kaddr));
+ return __pa(kaddr);
+ } else {
+ return page_to_phys(vmalloc_to_page(kaddr)) +
+ offset_in_page(kaddr);
+ }
+}
+
/**
* create_hyp_mappings - duplicate a kernel virtual address range in Hyp mode
* @from: The virtual kernel start address of the range
@@ -318,16 +329,27 @@ out:
*/
int create_hyp_mappings(void *from, void *to)
{
- unsigned long phys_addr = virt_to_phys(from);
+ phys_addr_t phys_addr;
+ unsigned long virt_addr;
unsigned long start = KERN_TO_HYP((unsigned long)from);
unsigned long end = KERN_TO_HYP((unsigned long)to);

- /* Check for a valid kernel memory mapping */
- if (!virt_addr_valid(from) || !virt_addr_valid(to - 1))
- return -EINVAL;
+ start = start & PAGE_MASK;
+ end = PAGE_ALIGN(end);

- return __create_hyp_mappings(hyp_pgd, start, end,
- __phys_to_pfn(phys_addr), PAGE_HYP);
+ for (virt_addr = start; virt_addr < end; virt_addr += PAGE_SIZE) {
+ int err;
+
+ phys_addr = kvm_kaddr_to_phys(from + virt_addr - start);
+ err = __create_hyp_mappings(hyp_pgd, virt_addr,
+ virt_addr + PAGE_SIZE,
+ __phys_to_pfn(phys_addr),
+ PAGE_HYP);
+ if (err)
+ return err;
+ }
+
+ return 0;
}

/**
--
1.8.3.2

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