From 0f69dae4d1069963fdcc16e63655927d83281006 Mon Sep 17 00:00:00 2001 From: Zhaoyang Huang Date: Fri, 31 Jul 2020 08:27:45 +0800 Subject: trace : Have tracing buffer info use kvzalloc instead of kzalloc MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit High order memory stuff within trace could introduce OOM, use kvzalloc instead. Please find the bellowing for the call stack we run across in an android system. The scenario happens when traced_probes is woken up to get a large quantity of trace even if free memory is even higher than watermark_low.  traced_probes invoked oom-killer: gfp_mask=0x140c0c0(GFP_KERNEL|__GFP_COMP|__GFP_ZERO), nodemask=(null), order=2, oom_score_adj=-1 traced_probes cpuset=system-background mems_allowed=0 CPU: 3 PID: 588 Comm: traced_probes Tainted: G W O 4.14.181 #1 Hardware name: Generic DT based system (unwind_backtrace) from [] (show_stack+0x20/0x24) (show_stack) from [] (dump_stack+0xa8/0xec) (dump_stack) from [] (dump_header+0x9c/0x220) (dump_header) from [] (oom_kill_process+0xc0/0x5c4) (oom_kill_process) from [] (out_of_memory+0x220/0x310) (out_of_memory) from [] (__alloc_pages_nodemask+0xff8/0x13a4) (__alloc_pages_nodemask) from [] (kmalloc_order+0x30/0x48) (kmalloc_order) from [] (kmalloc_order_trace+0x30/0x118) (kmalloc_order_trace) from [] (tracing_buffers_open+0x50/0xfc) (tracing_buffers_open) from [] (do_dentry_open+0x278/0x34c) (do_dentry_open) from [] (vfs_open+0x50/0x70) (vfs_open) from [] (path_openat+0x5fc/0x169c) (path_openat) from [] (do_filp_open+0x94/0xf8) (do_filp_open) from [] (do_sys_open+0x168/0x26c) (do_sys_open) from [] (SyS_openat+0x34/0x38) (SyS_openat) from [] (ret_fast_syscall+0x0/0x28) Link: https://lkml.kernel.org/r/1596155265-32365-1-git-send-email-zhaoyang.huang@unisoc.com Signed-off-by: Zhaoyang Huang Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index dbcacdd56b02..06c0feae5ff9 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -7402,7 +7402,7 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp) if (ret) return ret; - info = kzalloc(sizeof(*info), GFP_KERNEL); + info = kvzalloc(sizeof(*info), GFP_KERNEL); if (!info) { trace_array_put(tr); return -ENOMEM; @@ -7528,7 +7528,7 @@ static int tracing_buffers_release(struct inode *inode, struct file *file) if (info->spare) ring_buffer_free_read_page(iter->array_buffer->buffer, info->spare_cpu, info->spare); - kfree(info); + kvfree(info); mutex_unlock(&trace_types_lock); -- cgit v1.2.3-59-g8ed1b