Our Android phones occur Panic as follows:
[77522.303024][ T9734] Call trace:
[77522.303039][ T9734] dump_backtrace.cfi_jt+0x0/0x8
[77522.303052][ T9734] dump_stack_lvl+0xc4/0x140
[77522.303061][ T9734] dump_stack+0x1c/0x2c
[77522.303123][ T9734] mrdump_common_die+0x3a8/0x544 [mrdump]
[77522.303177][ T9734] ipanic_die+0x24/0x38 [mrdump]
[77522.303189][ T9734] die+0x340/0x698
[77522.303199][ T9734] bug_handler+0x48/0x108
[77522.303210][ T9734] brk_handler+0xac/0x1a8
[77522.303221][ T9734] do_debug_exception+0xe0/0x1e0
[77522.303233][ T9734] el1_dbg+0x38/0x54
[77522.303242][ T9734] el1_sync_handler+0x40/0x88
[77522.303255][ T9734] el1_sync+0x8c/0x140
[77522.303264][ T9734] plist_requeue+0xd4/0x110
[77522.303297][ T9734] tran_get_swap_pages+0xc8/0x364 [memfusion]
[77522.303329][ T9734] probe_android_vh_get_swap_page+0x1b4/0x220 [memfusion]
[77522.303342][ T9734] get_swap_page+0x258/0x304
[77522.303352][ T9734] shrink_page_list+0xe00/0x1e0c
[77522.303361][ T9734] shrink_inactive_list+0x2f4/0xac8
[77522.303373][ T9734] shrink_lruvec+0x1a4/0x34c
[77522.303383][ T9734] shrink_node_memcgs+0x84/0x3b0
[77522.303391][ T9734] shrink_node+0x2c4/0x6e4
[77522.303400][ T9734] shrink_zones+0x16c/0x29c
[77522.303410][ T9734] do_try_to_free_pages+0xe4/0x2bc
[77522.303418][ T9734] try_to_free_pages+0x388/0x7b4
[77522.303429][ T9734] __alloc_pages_direct_reclaim+0x88/0x278
[77522.303438][ T9734] __alloc_pages_slowpath+0x464/0xb24
[77522.303447][ T9734] __alloc_pages_nodemask+0x1f4/0x3dc
[77522.303458][ T9734] do_anonymous_page+0x164/0x914
[77522.303466][ T9734] handle_pte_fault+0x15c/0x9f8
[77522.303476][ T9734] ___handle_speculative_fault+0x234/0xe18
[77522.303485][ T9734] __handle_speculative_fault+0x78/0x21c
[77522.303497][ T9734] do_page_fault+0x36c/0x754
[77522.303506][ T9734] do_translation_fault+0x48/0x64
[77522.303514][ T9734] do_mem_abort+0x6c/0x164
[77522.303522][ T9734] el0_da+0x24/0x34
[77522.303531][ T9734] el0_sync_handler+0xc8/0xf0
[77522.303539][ T9734] el0_sync+0x1b4/0x1c0
The analysis shows that when we iterate the swap_avail_heads list, we get
node A, but before we access node A, node A is maybe deleted, and by the time
we actually access node A, it no longer exists, as follows:
CPU1 thread1 CPU2 thread2
plist_for_each_entry_safe()
get si->avail_lists[node] from swap_avail_heads
remove si->avail_lists[node] from swap_avail_heads
plist_requeue(&si->avail_lists[node])
BUG_ON(plist_node_empty(node)); // trigger
Due to when we use vendor hook of get_swap_page, the get_swap_pages() function
is overridden, use our own spin_lock to protect when iterate swap_avail_heads
list, but now use native swap_avail_lock spin_lock protect when the
swap_avail_heads list to add and delete nodes, so there will be concurrent
access.
So add vendor hook of add/delete/iterate node for avail_list, in this way, we
can use our own spin_lock to protect the swap_avail_heads list to add, delete
and iterate node.
Due to enable_swap_info function to call vendor hook of add_to_avail_list,
need first init swap_avail_heads, so also add vendor hook of
swap_avail_heads_init.
Due to the vendor hook of __cgroup_throttle_swaprate need to call
blkcg_schedule_throttle function, so export it also.
Bug: 225795494
Change-Id: I03107cbda6310fa7ae85e41b8cf1fa8225cafe78
Signed-off-by: Lincheng Yang <lincheng.yang@transsion.com>
Suggested-by: Bing Han <bing.han@transsion.com>
6356ed35b9