From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx149.postini.com [74.125.245.149]) by kanga.kvack.org (Postfix) with SMTP id 8966D6B0005 for ; Wed, 3 Apr 2013 21:12:00 -0400 (EDT) Received: by mail-pb0-f47.google.com with SMTP id rq13so1144971pbb.34 for ; Wed, 03 Apr 2013 18:11:59 -0700 (PDT) Message-ID: <515CD359.40004@gmail.com> Date: Thu, 04 Apr 2013 09:11:53 +0800 From: Simon Jeons MIME-Version: 1.0 Subject: Re: [PATCH] x86: add phys addr validity check for /dev/mem mmap References: <1364905733-23937-1-git-send-email-fhrbata@redhat.com> <515B2802.1050405@zytor.com> In-Reply-To: <515B2802.1050405@zytor.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: "H. Peter Anvin" Cc: Frantisek Hrbata , linux-kernel@vger.kernel.org, linux-mm@kvack.org, tglx@linutronix.de, mingo@redhat.com, x86@kernel.org, oleg@redhat.com, kamaleshb@in.ibm.com, hechjie@cn.ibm.com Hi H.Peter, On 04/03/2013 02:48 AM, H. Peter Anvin wrote: > On 04/02/2013 05:28 AM, Frantisek Hrbata wrote: >> diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h >> index d8e8eef..39607c6 100644 >> --- a/arch/x86/include/asm/io.h >> +++ b/arch/x86/include/asm/io.h >> @@ -242,6 +242,10 @@ static inline void flush_write_buffers(void) >> #endif >> } >> >> +#define ARCH_HAS_VALID_PHYS_ADDR_RANGE >> +extern int valid_phys_addr_range(phys_addr_t addr, size_t count); >> +extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t count); >> + >> #endif /* __KERNEL__ */ >> >> extern void native_io_delay(void); >> diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c >> index 845df68..92ec31c 100644 >> --- a/arch/x86/mm/mmap.c >> +++ b/arch/x86/mm/mmap.c >> @@ -31,6 +31,8 @@ >> #include >> #include >> >> +#include "physaddr.h" >> + >> struct __read_mostly va_alignment va_align = { >> .flags = -1, >> }; >> @@ -122,3 +124,14 @@ void arch_pick_mmap_layout(struct mm_struct *mm) >> mm->unmap_area = arch_unmap_area_topdown; >> } >> } >> + >> +int valid_phys_addr_range(phys_addr_t addr, size_t count) >> +{ >> + return addr + count <= __pa(high_memory); >> +} >> + >> +int valid_mmap_phys_addr_range(unsigned long pfn, size_t count) >> +{ >> + resource_size_t addr = (pfn << PAGE_SHIFT) + count; >> + return phys_addr_valid(addr); >> +} >> Why we consider boot_cpu_data.x86_phys_bits instead of e820 map here? > > -hpa > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org