Re: [PATCH 1/2] mm/zsmalloc.c: check encoded object value overflow for PAE

From: kbuild test robot
Date: Thu Oct 25 2018 - 08:43:08 EST

Next message: Vincent Guittot: "Re: [PATCH 00/10] steal tasks to improve CPU utilization"
Previous message: Dennis Wassenberg: "Re: USB-C device hotplug issue"
In reply to: Russell King - ARM Linux: "Re: [PATCH 1/2] mm/zsmalloc.c: check encoded object value overflow for PAE"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

Hi Rafael,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linux-sof-driver/master]
[also build test WARNING on v4.19 next-20181019]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url: https://github.com/0day-ci/linux/commits/Rafael-David-Tinoco/mm-zsmalloc-c-check-encoded-object-value-overflow-for-PAE/20181025-110258
base: https://github.com/thesofproject/linux master
config: um-allyesconfig (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=um

All warnings (new ones prefixed by >>):

In file included from include/linux/kernel.h:10:0,
from include/linux/list.h:9,
from include/linux/module.h:9,
from mm/zsmalloc.c:33:
mm/zsmalloc.c: In function 'location_to_obj':
>> mm/zsmalloc.c:129:17: warning: left shift count >= width of type [-Wshift-count-overflow]
((_AC(1, ULL)) << MAX_POSSIBLE_PHYSMEM_BITS) ? 1 : 0)
^
include/linux/compiler.h:77:42: note: in definition of macro 'unlikely'
# define unlikely(x) __builtin_expect(!!(x), 0)
^
>> mm/zsmalloc.c:886:15: note: in expansion of macro 'OBJ_OVERFLOW'
if (unlikely(OBJ_OVERFLOW(pfn)))
^~~~~~~~~~~~
Cyclomatic Complexity 5 include/linux/compiler.h:__read_once_size
Cyclomatic Complexity 5 include/linux/compiler.h:__write_once_size
Cyclomatic Complexity 1 include/linux/kasan-checks.h:kasan_check_read
Cyclomatic Complexity 1 include/linux/kasan-checks.h:kasan_check_write
Cyclomatic Complexity 2 arch/x86/include/asm/bitops.h:set_bit
Cyclomatic Complexity 2 arch/x86/include/asm/bitops.h:clear_bit
Cyclomatic Complexity 1 arch/x86/include/asm/bitops.h:clear_bit_unlock
Cyclomatic Complexity 1 arch/x86/include/asm/bitops.h:test_and_set_bit
Cyclomatic Complexity 1 arch/x86/include/asm/bitops.h:test_and_set_bit_lock
Cyclomatic Complexity 1 arch/x86/include/asm/bitops.h:constant_test_bit
Cyclomatic Complexity 1 arch/x86/include/asm/bitops.h:variable_test_bit
Cyclomatic Complexity 1 arch/x86/include/asm/bitops.h:fls64
Cyclomatic Complexity 1 include/linux/log2.h:__ilog2_u64
Cyclomatic Complexity 1 include/linux/kernel.h:___might_sleep
Cyclomatic Complexity 1 include/linux/list.h:INIT_LIST_HEAD
Cyclomatic Complexity 2 include/linux/list.h:__list_add
Cyclomatic Complexity 1 include/linux/list.h:list_add
Cyclomatic Complexity 1 include/linux/list.h:__list_del
Cyclomatic Complexity 2 include/linux/list.h:__list_del_entry
Cyclomatic Complexity 1 include/linux/list.h:list_del
Cyclomatic Complexity 1 include/linux/list.h:list_del_init
Cyclomatic Complexity 1 include/linux/list.h:list_empty
Cyclomatic Complexity 1 include/linux/list.h:__list_splice
Cyclomatic Complexity 2 include/linux/list.h:list_splice_init
Cyclomatic Complexity 1 arch/um/include/shared/mem.h:to_virt
Cyclomatic Complexity 1 include/asm-generic/getorder.h:__get_order
Cyclomatic Complexity 1 arch/um/include/asm/thread_info.h:current_thread_info
Cyclomatic Complexity 1 include/asm-generic/preempt.h:preempt_count
Cyclomatic Complexity 1 arch/x86/include/asm/atomic.h:arch_atomic_read
Cyclomatic Complexity 1 arch/x86/include/asm/atomic.h:arch_atomic_set
Cyclomatic Complexity 1 arch/x86/include/asm/atomic.h:arch_atomic_inc
Cyclomatic Complexity 1 arch/x86/include/asm/atomic.h:arch_atomic_dec_and_test
Cyclomatic Complexity 1 arch/x86/include/asm/atomic64_64.h:arch_atomic64_read
Cyclomatic Complexity 1 arch/x86/include/asm/atomic64_64.h:arch_atomic64_add
Cyclomatic Complexity 1 arch/x86/include/asm/atomic64_64.h:arch_atomic64_sub
Cyclomatic Complexity 1 arch/x86/include/asm/atomic64_64.h:arch_atomic64_inc
Cyclomatic Complexity 1 arch/x86/include/asm/atomic64_64.h:arch_atomic64_dec
Cyclomatic Complexity 1 include/asm-generic/atomic-instrumented.h:atomic_read
Cyclomatic Complexity 1 include/asm-generic/atomic-instrumented.h:atomic64_read
Cyclomatic Complexity 1 include/asm-generic/atomic-instrumented.h:atomic_set
Cyclomatic Complexity 1 include/asm-generic/atomic-instrumented.h:atomic_inc
Cyclomatic Complexity 1 include/asm-generic/atomic-instrumented.h:atomic64_inc
Cyclomatic Complexity 1 include/asm-generic/atomic-instrumented.h:atomic64_dec
Cyclomatic Complexity 1 include/asm-generic/atomic-instrumented.h:atomic64_add
Cyclomatic Complexity 1 include/asm-generic/atomic-instrumented.h:atomic64_sub
Cyclomatic Complexity 1 include/asm-generic/atomic-instrumented.h:atomic_dec_and_test
Cyclomatic Complexity 1 include/asm-generic/atomic-long.h:atomic_long_read
Cyclomatic Complexity 1 include/asm-generic/atomic-long.h:atomic_long_inc
Cyclomatic Complexity 1 include/asm-generic/atomic-long.h:atomic_long_dec
Cyclomatic Complexity 1 include/asm-generic/atomic-long.h:atomic_long_add
Cyclomatic Complexity 1 include/asm-generic/atomic-long.h:atomic_long_sub
Cyclomatic Complexity 1 arch/x86/um/asm/processor.h:rep_nop
Cyclomatic Complexity 1 include/linux/spinlock.h:spinlock_check
Cyclomatic Complexity 1 include/linux/spinlock.h:spin_lock
Cyclomatic Complexity 1 include/linux/spinlock.h:spin_unlock
Cyclomatic Complexity 1 include/linux/jump_label.h:static_key_count
Cyclomatic Complexity 2 include/linux/jump_label.h:static_key_false
Cyclomatic Complexity 1 include/linux/nodemask.h:node_state
Cyclomatic Complexity 1 include/linux/err.h:PTR_ERR
Cyclomatic Complexity 1 include/linux/err.h:IS_ERR
Cyclomatic Complexity 1 include/linux/workqueue.h:queue_work
Cyclomatic Complexity 1 include/linux/workqueue.h:schedule_work
Cyclomatic Complexity 1 include/linux/topology.h:numa_node_id
Cyclomatic Complexity 1 include/linux/topology.h:numa_mem_id
Cyclomatic Complexity 1 include/linux/gfp.h:__alloc_pages
Cyclomatic Complexity 4 include/linux/gfp.h:__alloc_pages_node
Cyclomatic Complexity 2 include/linux/gfp.h:alloc_pages_node
Cyclomatic Complexity 4 include/linux/bit_spinlock.h:bit_spin_lock
Cyclomatic Complexity 2 include/linux/bit_spinlock.h:bit_spin_trylock
Cyclomatic Complexity 2 include/linux/bit_spinlock.h:bit_spin_unlock
Cyclomatic Complexity 2 include/linux/bit_spinlock.h:bit_spin_is_locked
Cyclomatic Complexity 1 include/linux/fs.h:mount_pseudo
Cyclomatic Complexity 2 include/linux/page-flags.h:compound_head
Cyclomatic Complexity 1 include/linux/page-flags.h:PagePoisoned
Cyclomatic Complexity 1 include/linux/page-flags.h:PageLocked
Cyclomatic Complexity 1 include/linux/page-flags.h:PagePrivate
Cyclomatic Complexity 1 include/linux/page-flags.h:SetPagePrivate
Cyclomatic Complexity 1 include/linux/page-flags.h:ClearPagePrivate
Cyclomatic Complexity 1 include/linux/page-flags.h:PageOwnerPriv1
Cyclomatic Complexity 1 include/linux/page-flags.h:SetPageOwnerPriv1
Cyclomatic Complexity 1 include/linux/page-flags.h:ClearPageOwnerPriv1
Cyclomatic Complexity 1 include/linux/page-flags.h:PageIsolated
Cyclomatic Complexity 1 include/linux/page_ref.h:page_ref_count
Cyclomatic Complexity 2 include/linux/page_ref.h:page_ref_inc
Cyclomatic Complexity 2 include/linux/page_ref.h:page_ref_dec_and_test
Cyclomatic Complexity 1 include/linux/mm.h:put_page_testzero
Cyclomatic Complexity 1 include/linux/mm.h:page_mapcount_reset
Cyclomatic Complexity 1 include/linux/mm.h:page_zonenum
Cyclomatic Complexity 1 include/linux/mm.h:get_page
Cyclomatic Complexity 2 include/linux/mm.h:put_page
Cyclomatic Complexity 1 include/linux/mm.h:page_zone
Cyclomatic Complexity 1 include/linux/vmstat.h:__inc_zone_state
Cyclomatic Complexity 1 include/linux/vmstat.h:__dec_zone_state
Cyclomatic Complexity 1 include/linux/vmstat.h:__inc_zone_page_state
Cyclomatic Complexity 1 include/linux/vmstat.h:__dec_zone_page_state
Cyclomatic Complexity 1 include/linux/mm.h:lowmem_page_address
Cyclomatic Complexity 1 include/linux/uaccess.h:pagefault_disabled_inc
Cyclomatic Complexity 1 include/linux/uaccess.h:pagefault_disabled_dec

vim +129 mm/zsmalloc.c

32
> 33 #include <linux/module.h>
34 #include <linux/kernel.h>
35 #include <linux/sched.h>
36 #include <linux/magic.h>
37 #include <linux/bitops.h>
38 #include <linux/errno.h>
39 #include <linux/highmem.h>
40 #include <linux/string.h>
41 #include <linux/slab.h>
42 #include <asm/tlbflush.h>
43 #include <asm/pgtable.h>
44 #include <linux/cpumask.h>
45 #include <linux/cpu.h>
46 #include <linux/vmalloc.h>
47 #include <linux/preempt.h>
48 #include <linux/spinlock.h>
49 #include <linux/shrinker.h>
50 #include <linux/types.h>
51 #include <linux/debugfs.h>
52 #include <linux/zsmalloc.h>
53 #include <linux/zpool.h>
54 #include <linux/mount.h>
55 #include <linux/migrate.h>
56 #include <linux/pagemap.h>
57 #include <linux/fs.h>
58
59 #define ZSPAGE_MAGIC 0x58
60
61 /*
62 * This must be power of 2 and greater than of equal to sizeof(link_free).
63 * These two conditions ensure that any 'struct link_free' itself doesn't
64 * span more than 1 page which avoids complex case of mapping 2 pages simply
65 * to restore link_free pointer values.
66 */
67 #define ZS_ALIGN 8
68
69 /*
70 * A single 'zspage' is composed of up to 2^N discontiguous 0-order (single)
71 * pages. ZS_MAX_ZSPAGE_ORDER defines upper limit on N.
72 */
73 #define ZS_MAX_ZSPAGE_ORDER 2
74 #define ZS_MAX_PAGES_PER_ZSPAGE (_AC(1, UL) << ZS_MAX_ZSPAGE_ORDER)
75
76 #define ZS_HANDLE_SIZE (sizeof(unsigned long))
77
78 /*
79 * Object location (<PFN>, <obj_idx>) is encoded as
80 * as single (unsigned long) handle value.
81 *
82 * Note that object index <obj_idx> starts from 0.
83 *
84 * This is made more complicated by various memory models and PAE.
85 */
86
87 #ifndef MAX_POSSIBLE_PHYSMEM_BITS
88 #ifdef MAX_PHYSMEM_BITS
89 #define MAX_POSSIBLE_PHYSMEM_BITS MAX_PHYSMEM_BITS
90 #else
91 /*
92 * If this definition of MAX_PHYSMEM_BITS is used, OBJ_INDEX_BITS will just
93 * be PAGE_SHIFT
94 */
95 #define MAX_POSSIBLE_PHYSMEM_BITS BITS_PER_LONG
96 #endif
97 #endif
98
99 #define _PFN_BITS (MAX_POSSIBLE_PHYSMEM_BITS - PAGE_SHIFT)
100
101 /*
102 * Memory for allocating for handle keeps object position by
103 * encoding <page, obj_idx> and the encoded value has a room
104 * in least bit(ie, look at obj_to_location).
105 * We use the bit to synchronize between object access by
106 * user and migration.
107 */
108 #define HANDLE_PIN_BIT 0
109
110 /*
111 * Head in allocated object should have OBJ_ALLOCATED_TAG
112 * to identify the object was allocated or not.
113 * It's okay to add the status bit in the least bit because
114 * header keeps handle which is 4byte-aligned address so we
115 * have room for two bit at least.
116 */
117 #define OBJ_ALLOCATED_TAG 1
118 #define OBJ_TAG_BITS 1
119 #define OBJ_INDEX_BITS (BITS_PER_LONG - _PFN_BITS - OBJ_TAG_BITS)
120 #define OBJ_INDEX_MASK ((_AC(1, UL) << OBJ_INDEX_BITS) - 1)
121
122 /*
123 * When using PAE, the obj encoding might overflow if arch does
124 * not re-define MAX_PHYSMEM_BITS, since zsmalloc uses HIGHMEM.
125 * This checks for a future bad page access, when de-coding obj.
126 */
127 #define OBJ_OVERFLOW(_pfn) \
128 (((unsigned long long) _pfn << (OBJ_INDEX_BITS + OBJ_TAG_BITS)) >= \
> 129 ((_AC(1, ULL)) << MAX_POSSIBLE_PHYSMEM_BITS) ? 1 : 0)
130

---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation

Attachment: .config.gz
Description: application/gzip

Next message: Vincent Guittot: "Re: [PATCH 00/10] steal tasks to improve CPU utilization"
Previous message: Dennis Wassenberg: "Re: USB-C device hotplug issue"
In reply to: Russell King - ARM Linux: "Re: [PATCH 1/2] mm/zsmalloc.c: check encoded object value overflow for PAE"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]