From patchwork Thu Aug 18 14:43:52 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Catalin Marinas X-Patchwork-Id: 74201 Delivered-To: patch@linaro.org Received: by 10.140.29.52 with SMTP id a49csp71496qga; Thu, 18 Aug 2016 18:22:21 -0700 (PDT) X-Received: by 10.66.12.102 with SMTP id x6mr8840632pab.48.1471569740965; Thu, 18 Aug 2016 18:22:20 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id k29si2115261pfk.57.2016.08.18.18.22.20; Thu, 18 Aug 2016 18:22:20 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932298AbcHSBWI (ORCPT + 27 others); Thu, 18 Aug 2016 21:22:08 -0400 Received: from foss.arm.com ([217.140.101.70]:33191 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754724AbcHSBVn (ORCPT ); Thu, 18 Aug 2016 21:21:43 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id DD66830C; Thu, 18 Aug 2016 07:45:32 -0700 (PDT) Received: from e104818-lin.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 6A3C93F213; Thu, 18 Aug 2016 07:43:57 -0700 (PDT) From: Catalin Marinas To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Vignesh R , Andrew Morton Subject: [PATCH v3] mm: kmemleak: Avoid using __va() on addresses that don't have a lowmem mapping Date: Thu, 18 Aug 2016 15:43:52 +0100 Message-Id: <1471531432-16503-1-git-send-email-catalin.marinas@arm.com> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some of the kmemleak_*() callbacks in memblock, bootmem, CMA convert a physical address to a virtual one using __va(). However, such physical addresses may sometimes be located in highmem and using __va() is incorrect, leading to inconsistent object tracking in kmemleak. The following functions have been added to the kmemleak API and they take a physical address as the object pointer. They only perform the corresponding action if the address has a lowmem mapping: kmemleak_alloc_phys kmemleak_free_part_phys kmemleak_not_leak_phys kmemleak_ignore_phys The affected calling places have been updated to use the new kmemleak API. Reported-by: Vignesh R Cc: Vignesh R Cc: Andrew Morton Signed-off-by: Catalin Marinas --- v2->v3: Replaced the __pa(high_memory) check with PHYS_PFN(phys) < max_low_pfn as the former does not always give the right result and causes a kernel panic on x86 (__pa(high_memory - 1) should have probably worked as well). Documentation/kmemleak.txt | 9 +++++++++ include/linux/kmemleak.h | 18 ++++++++++++++++++ mm/bootmem.c | 6 +++--- mm/cma.c | 2 +- mm/kmemleak.c | 47 ++++++++++++++++++++++++++++++++++++++++++++++ mm/memblock.c | 8 ++++---- mm/nobootmem.c | 2 +- 7 files changed, 83 insertions(+), 9 deletions(-) diff --git a/Documentation/kmemleak.txt b/Documentation/kmemleak.txt index 18e24abb3ecf..35e1a8891e3a 100644 --- a/Documentation/kmemleak.txt +++ b/Documentation/kmemleak.txt @@ -155,6 +155,15 @@ kmemleak_erase - erase an old value in a pointer variable kmemleak_alloc_recursive - as kmemleak_alloc but checks the recursiveness kmemleak_free_recursive - as kmemleak_free but checks the recursiveness +The following functions take a physical address as the object pointer +and only perform the corresponding action if the address has a lowmem +mapping: + +kmemleak_alloc_phys +kmemleak_free_part_phys +kmemleak_not_leak_phys +kmemleak_ignore_phys + Dealing with false positives/negatives -------------------------------------- diff --git a/include/linux/kmemleak.h b/include/linux/kmemleak.h index 4894c6888bc6..1c2a32829620 100644 --- a/include/linux/kmemleak.h +++ b/include/linux/kmemleak.h @@ -38,6 +38,11 @@ extern void kmemleak_not_leak(const void *ptr) __ref; extern void kmemleak_ignore(const void *ptr) __ref; extern void kmemleak_scan_area(const void *ptr, size_t size, gfp_t gfp) __ref; extern void kmemleak_no_scan(const void *ptr) __ref; +extern void kmemleak_alloc_phys(phys_addr_t phys, size_t size, int min_count, + gfp_t gfp) __ref; +extern void kmemleak_free_part_phys(phys_addr_t phys, size_t size) __ref; +extern void kmemleak_not_leak_phys(phys_addr_t phys) __ref; +extern void kmemleak_ignore_phys(phys_addr_t phys) __ref; static inline void kmemleak_alloc_recursive(const void *ptr, size_t size, int min_count, unsigned long flags, @@ -106,6 +111,19 @@ static inline void kmemleak_erase(void **ptr) static inline void kmemleak_no_scan(const void *ptr) { } +static inline void kmemleak_alloc_phys(phys_addr_t phys, size_t size, + int min_count, gfp_t gfp) +{ +} +static inline void kmemleak_free_part_phys(phys_addr_t phys, size_t size) +{ +} +static inline void kmemleak_not_leak_phys(phys_addr_t phys) +{ +} +static inline void kmemleak_ignore_phys(phys_addr_t phys) +{ +} #endif /* CONFIG_DEBUG_KMEMLEAK */ diff --git a/mm/bootmem.c b/mm/bootmem.c index 0aa7dda52402..80f1d70bad2d 100644 --- a/mm/bootmem.c +++ b/mm/bootmem.c @@ -158,7 +158,7 @@ void __init free_bootmem_late(unsigned long physaddr, unsigned long size) { unsigned long cursor, end; - kmemleak_free_part(__va(physaddr), size); + kmemleak_free_part_phys(physaddr, size); cursor = PFN_UP(physaddr); end = PFN_DOWN(physaddr + size); @@ -402,7 +402,7 @@ void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr, { unsigned long start, end; - kmemleak_free_part(__va(physaddr), size); + kmemleak_free_part_phys(physaddr, size); start = PFN_UP(physaddr); end = PFN_DOWN(physaddr + size); @@ -423,7 +423,7 @@ void __init free_bootmem(unsigned long physaddr, unsigned long size) { unsigned long start, end; - kmemleak_free_part(__va(physaddr), size); + kmemleak_free_part_phys(physaddr, size); start = PFN_UP(physaddr); end = PFN_DOWN(physaddr + size); diff --git a/mm/cma.c b/mm/cma.c index bd0e1412475e..384c2cb51b56 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -336,7 +336,7 @@ int __init cma_declare_contiguous(phys_addr_t base, * kmemleak scans/reads tracked objects for pointers to other * objects but this address isn't mapped and accessible */ - kmemleak_ignore(phys_to_virt(addr)); + kmemleak_ignore_phys(addr); base = addr; } diff --git a/mm/kmemleak.c b/mm/kmemleak.c index 086292f7c59d..a5e453cf05c4 100644 --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -90,6 +90,8 @@ #include #include #include +#include +#include #include #include #include @@ -1121,6 +1123,51 @@ void __ref kmemleak_no_scan(const void *ptr) } EXPORT_SYMBOL(kmemleak_no_scan); +/** + * kmemleak_alloc_phys - similar to kmemleak_alloc but taking a physical + * address argument + */ +void __ref kmemleak_alloc_phys(phys_addr_t phys, size_t size, int min_count, + gfp_t gfp) +{ + if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn) + kmemleak_alloc(__va(phys), size, min_count, gfp); +} +EXPORT_SYMBOL(kmemleak_alloc_phys); + +/** + * kmemleak_free_part_phys - similar to kmemleak_free_part but taking a + * physical address argument + */ +void __ref kmemleak_free_part_phys(phys_addr_t phys, size_t size) +{ + if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn) + kmemleak_free_part(__va(phys), size); +} +EXPORT_SYMBOL(kmemleak_free_part_phys); + +/** + * kmemleak_not_leak_phys - similar to kmemleak_not_leak but taking a physical + * address argument + */ +void __ref kmemleak_not_leak_phys(phys_addr_t phys) +{ + if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn) + kmemleak_not_leak(__va(phys)); +} +EXPORT_SYMBOL(kmemleak_not_leak_phys); + +/** + * kmemleak_ignore_phys - similar to kmemleak_ignore but taking a physical + * address argument + */ +void __ref kmemleak_ignore_phys(phys_addr_t phys) +{ + if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn) + kmemleak_ignore(__va(phys)); +} +EXPORT_SYMBOL(kmemleak_ignore_phys); + /* * Update an object's checksum and return true if it was modified. */ diff --git a/mm/memblock.c b/mm/memblock.c index 483197ef613f..30ecea7b45d1 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -723,7 +723,7 @@ int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size) (unsigned long long)base + size - 1, (void *)_RET_IP_); - kmemleak_free_part(__va(base), size); + kmemleak_free_part_phys(base, size); return memblock_remove_range(&memblock.reserved, base, size); } @@ -1152,7 +1152,7 @@ static phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size, * The min_count is set to 0 so that memblock allocations are * never reported as leaks. */ - kmemleak_alloc(__va(found), size, 0, 0); + kmemleak_alloc_phys(found, size, 0, 0); return found; } return 0; @@ -1399,7 +1399,7 @@ void __init __memblock_free_early(phys_addr_t base, phys_addr_t size) memblock_dbg("%s: [%#016llx-%#016llx] %pF\n", __func__, (u64)base, (u64)base + size - 1, (void *)_RET_IP_); - kmemleak_free_part(__va(base), size); + kmemleak_free_part_phys(base, size); memblock_remove_range(&memblock.reserved, base, size); } @@ -1419,7 +1419,7 @@ void __init __memblock_free_late(phys_addr_t base, phys_addr_t size) memblock_dbg("%s: [%#016llx-%#016llx] %pF\n", __func__, (u64)base, (u64)base + size - 1, (void *)_RET_IP_); - kmemleak_free_part(__va(base), size); + kmemleak_free_part_phys(base, size); cursor = PFN_UP(base); end = PFN_DOWN(base + size); diff --git a/mm/nobootmem.c b/mm/nobootmem.c index bd05a70f44b9..a056d31dff7e 100644 --- a/mm/nobootmem.c +++ b/mm/nobootmem.c @@ -81,7 +81,7 @@ void __init free_bootmem_late(unsigned long addr, unsigned long size) { unsigned long cursor, end; - kmemleak_free_part(__va(addr), size); + kmemleak_free_part_phys(addr, size); cursor = PFN_UP(addr); end = PFN_DOWN(addr + size);