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

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

[Christoffer Dall]

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@ti.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---

This patch is loosely based on Marc's previous patch from today but
instead of introducing another Hyp mapping function, it fixes the
existing one to deal with both kinds of kernel addresses.

 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 3719583..5809069 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -334,6 +334,17 @@ 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
@@ -345,16 +356,27 @@ 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;
 }
 
 /**
-- 
1.7.10.4

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

[Marc Zyngier]

On 2013-11-15 23:24, Christoffer Dall wrote:
> 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@ti.com>
> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
> ---
>
> This patch is loosely based on Marc's previous patch from today but
> instead of introducing another Hyp mapping function, it fixes the
> existing one to deal with both kinds of kernel addresses.

Looks good to me! This should probably be merged quickly (after testing 
by Santosh), and possibly Cc-ed to stable.

Thanks,

         M.

>
>  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 3719583..5809069 100644
> --- a/arch/arm/kvm/mmu.c
> +++ b/arch/arm/kvm/mmu.c
> @@ -334,6 +334,17 @@ 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
> @@ -345,16 +356,27 @@ 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;
>  }
>
>  /**

-- 
Fast, cheap, reliable. Pick two.

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

[Christoffer Dall]

On Sat, Nov 16, 2013 at 10:01:01AM +0000, Marc Zyngier wrote:
> On 2013-11-15 23:24, Christoffer Dall wrote:
> >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@ti.com>
> >Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
> >Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
> >---
> >
> >This patch is loosely based on Marc's previous patch from today but
> >instead of introducing another Hyp mapping function, it fixes the
> >existing one to deal with both kinds of kernel addresses.
> 
> Looks good to me! This should probably be merged quickly (after
> testing by Santosh), and possibly Cc-ed to stable.
> 
Agreed, Santhos, can you give this a quick spin?

-Christoffer

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

[Santosh Shilimkar]

On Saturday 16 November 2013 12:15 PM, Christoffer Dall wrote:
> On Sat, Nov 16, 2013 at 10:01:01AM +0000, Marc Zyngier wrote:
>> On 2013-11-15 23:24, Christoffer Dall wrote:
>>> 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@ti.com>
>>> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
>>> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
>>> ---
>>>
>>> This patch is loosely based on Marc's previous patch from today but
>>> instead of introducing another Hyp mapping function, it fixes the
>>> existing one to deal with both kinds of kernel addresses.
>>
>> Looks good to me! This should probably be merged quickly (after
>> testing by Santosh), and possibly Cc-ed to stable.
>>
> Agreed, Santhos, can you give this a quick spin?
> 
Works as expected.

Regards,
Santosh

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

[Christoffer Dall]

On 16 November 2013 15:30, Santosh Shilimkar <santosh.shilimkar@ti.com> wrote:
> On Saturday 16 November 2013 12:15 PM, Christoffer Dall wrote:
>> On Sat, Nov 16, 2013 at 10:01:01AM +0000, Marc Zyngier wrote:
>>> On 2013-11-15 23:24, Christoffer Dall wrote:
>>>> 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@ti.com>
>>>> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
>>>> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
>>>> ---
>>>>
>>>> This patch is loosely based on Marc's previous patch from today but
>>>> instead of introducing another Hyp mapping function, it fixes the
>>>> existing one to deal with both kinds of kernel addresses.
>>>
>>> Looks good to me! This should probably be merged quickly (after
>>> testing by Santosh), and possibly Cc-ed to stable.
>>>
>> Agreed, Santhos, can you give this a quick spin?
>>
> Works as expected.
>
great, I'll merge the patch.  Thanks for testing it.

-Christoffer

[GIT PULL] Fix vmalloc allocations for KVM/ARM

[Christoffer Dall]

Hi Gleb and Paolo,

Please pull this into kvm/master:

The following changes since commit 5e01dc7b26d9f24f39abace5da98ccbd6a5ceb52:

  Linux 3.12 (2013-11-03 15:41:51 -0800)

are available in the git repository at:

  git://git.linaro.org/people/cdall/linux-kvm-arm.git tags/kvm-arm-fixes-3.13-1

for you to fetch changes up to 40c2729bab48e2832b17c1fa8af9db60e776131b:

  arm/arm64: KVM: Fix hyp mappings of vmalloc regions (2013-11-16 18:54:45 -0800)

----------------------------------------------------------------
Fix percpu vmalloc allocations

----------------------------------------------------------------
Christoffer Dall (1):
      arm/arm64: KVM: Fix hyp mappings of vmalloc regions

 arch/arm/kvm/mmu.c |   34 ++++++++++++++++++++++++++++------
 1 file changed, 28 insertions(+), 6 deletions(-)

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

[Christoffer Dall]

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.

Cc: Stable <stable@vger.kernel.org>        [3.10+]
Reported-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 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 b0de86b..cb79a5d 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;
 }
 
 /**
-- 
1.7.10.4