Hi, All,

Please ignore this stupid email thread. I thought I had suppressed cc in gitconfig. But I am wrong...

Very very sorry!

Thanks Alex

On 2018/11/28 7:29 PM, Alex Shi wrote:

From: Dexuan Cui decui@microsoft.com

commit d1cd1210834649ce1ca6bafe5ac25d2f40331343 upstream.

pte_pfn() returns a PFN of long (32 bits in 32-PAE), so "long << PAGE_SHIFT" will overflow for PFNs above 4GB.

Due to this issue, some Linux 32-PAE distros, running as guests on Hyper-V, with 5GB memory assigned, can't load the netvsc driver successfully and hence the synthetic network device can't work (we can use the kernel parameter mem=3000M to work around the issue).

Cast pte_pfn() to phys_addr_t before shifting.

Fixes: "commit d76565344512: x86, mm: Create slow_virt_to_phys()" Signed-off-by: Dexuan Cui decui@microsoft.com Cc: K. Y. Srinivasan kys@microsoft.com Cc: Haiyang Zhang haiyangz@microsoft.com Cc: gregkh@linuxfoundation.org Cc: linux-mm@kvack.org Cc: olaf@aepfle.de Cc: apw@canonical.com Cc: jasowang@redhat.com Cc: dave.hansen@intel.com Cc: riel@redhat.com Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1414580017-27444-1-git-send-email-decui@microsoft.c... Signed-off-by: Thomas Gleixner tglx@linutronix.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Alex Shi alex.shi@linux.alibaba.com

---

7u/arch/x86/mm/pageattr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/7u/arch/x86/mm/pageattr.c b/7u/arch/x86/mm/pageattr.c index 4ed2b2d..81b82f4 100644 --- a/7u/arch/x86/mm/pageattr.c +++ b/7u/arch/x86/mm/pageattr.c @@ -405,7 +405,7 @@ phys_addr_t slow_virt_to_phys(void *__virt_addr) psize = page_level_size(level); pmask = page_level_mask(level); offset = virt_addr & ~pmask;

• phys_addr = pte_pfn(*pte) << PAGE_SHIFT;

• phys_addr = (phys_addr_t)pte_pfn(*pte) << PAGE_SHIFT; return (phys_addr | offset);

} EXPORT_SYMBOL_GPL(slow_virt_to_phys);