[PATCH 7/7] arm64: uprobes - ARM32 instruction probing
From: oleg@redhat.com (Oleg Nesterov)
Date: 2018-01-24 16:13:38
On 01/24, Maciej Slodczyk wrote:
Detect what kind of instruction is being probed and depending on the result: - if an A64 instruction handle it the old way, using existing A64 instructions probing code, - if an A32 instruction decode it and handle using the new code, moved from 32 bit arm kernel tree.
how this connects to the change in prepare_uretprobe(),
quoted hunk ↗ jump to hunk
--- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c@@ -1566,6 +1566,9 @@ static void prepare_uretprobe(struct uprobe *uprobe, struct pt_regs *regs) unsigned long orig_ret_vaddr, trampoline_vaddr; bool chained; + if (!current->mm) + return; +
? and how it is possible to hit ->mm == NULL here? Oleg.