| Message ID | 1443637392-6679-1-git-send-email-yang.shi@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, 30 Sep 2015 11:23:12 -0700 Yang Shi <yang.shi@linaro.org> wrote: > When running kprobe test on arm64 rt kernel, it reports the below warning: > > root@qemu7:~# modprobe kprobe_example > BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917 > in_atomic(): 0, irqs_disabled(): 128, pid: 484, name: modprobe > CPU: 0 PID: 484 Comm: modprobe Not tainted 4.1.6-rt5 #2 > Hardware name: linux,dummy-virt (DT) > Call trace: > [<ffffffc0000891b8>] dump_backtrace+0x0/0x128 > [<ffffffc000089300>] show_stack+0x20/0x30 > [<ffffffc00061dae8>] dump_stack+0x1c/0x28 > [<ffffffc0000bbad0>] ___might_sleep+0x120/0x198 > [<ffffffc0006223e8>] rt_spin_lock+0x28/0x40 > [<ffffffc000622b30>] __aarch64_insn_write+0x28/0x78 > [<ffffffc000622e48>] aarch64_insn_patch_text_nosync+0x18/0x48 > [<ffffffc000622ee8>] aarch64_insn_patch_text_cb+0x70/0xa0 OK, the above is called from stomp_machine(). > [<ffffffc000622f40>] aarch64_insn_patch_text_sync+0x28/0x48 > [<ffffffc0006236e0>] arch_arm_kprobe+0x38/0x48 > [<ffffffc00010e6f4>] arm_kprobe+0x34/0x50 > [<ffffffc000110374>] register_kprobe+0x4cc/0x5b8 > [<ffffffbffc002038>] kprobe_init+0x38/0x7c [kprobe_example] > [<ffffffc000084240>] do_one_initcall+0x90/0x1b0 > [<ffffffc00061c498>] do_init_module+0x6c/0x1cc > [<ffffffc0000fd0c0>] load_module+0x17f8/0x1db0 > [<ffffffc0000fd8cc>] SyS_finit_module+0xb4/0xc8 > > Convert patch_lock to raw loc kto avoid this issue. Yeah, I don't see anything in that lock that can sleep, or should take too much time (it's under stomp_machine). Looks like that should be raw. Acked-by: Steven Rostedt <rostedt@goodmis.org> -- Steve > > Although the problem is found on rt kernel, the fix should be applicable to > mainline kernel too. > > Signed-off-by: Yang Shi <yang.shi@linaro.org> > --- > arch/arm64/kernel/insn.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c > index f341866..c08b9ad 100644 > --- a/arch/arm64/kernel/insn.c > +++ b/arch/arm64/kernel/insn.c > @@ -85,7 +85,7 @@ bool aarch64_insn_is_branch_imm(u32 insn) > aarch64_insn_is_bcond(insn)); > } > > -static DEFINE_SPINLOCK(patch_lock); > +static DEFINE_RAW_SPINLOCK(patch_lock); > > static void __kprobes *patch_map(void *addr, int fixmap) > { > @@ -131,13 +131,13 @@ static int __kprobes __aarch64_insn_write(void *addr, u32 insn) > unsigned long flags = 0; > int ret; > > - spin_lock_irqsave(&patch_lock, flags); > + raw_spin_lock_irqsave(&patch_lock, flags); > waddr = patch_map(addr, FIX_TEXT_POKE0); > > ret = probe_kernel_write(waddr, &insn, AARCH64_INSN_SIZE); > > patch_unmap(FIX_TEXT_POKE0); > - spin_unlock_irqrestore(&patch_lock, flags); > + raw_spin_unlock_irqrestore(&patch_lock, flags); > > return ret; > }
diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c index f341866..c08b9ad 100644 --- a/arch/arm64/kernel/insn.c +++ b/arch/arm64/kernel/insn.c @@ -85,7 +85,7 @@ bool aarch64_insn_is_branch_imm(u32 insn) aarch64_insn_is_bcond(insn)); } -static DEFINE_SPINLOCK(patch_lock); +static DEFINE_RAW_SPINLOCK(patch_lock); static void __kprobes *patch_map(void *addr, int fixmap) { @@ -131,13 +131,13 @@ static int __kprobes __aarch64_insn_write(void *addr, u32 insn) unsigned long flags = 0; int ret; - spin_lock_irqsave(&patch_lock, flags); + raw_spin_lock_irqsave(&patch_lock, flags); waddr = patch_map(addr, FIX_TEXT_POKE0); ret = probe_kernel_write(waddr, &insn, AARCH64_INSN_SIZE); patch_unmap(FIX_TEXT_POKE0); - spin_unlock_irqrestore(&patch_lock, flags); + raw_spin_unlock_irqrestore(&patch_lock, flags); return ret; }
When running kprobe test on arm64 rt kernel, it reports the below warning: root@qemu7:~# modprobe kprobe_example BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917 in_atomic(): 0, irqs_disabled(): 128, pid: 484, name: modprobe CPU: 0 PID: 484 Comm: modprobe Not tainted 4.1.6-rt5 #2 Hardware name: linux,dummy-virt (DT) Call trace: [<ffffffc0000891b8>] dump_backtrace+0x0/0x128 [<ffffffc000089300>] show_stack+0x20/0x30 [<ffffffc00061dae8>] dump_stack+0x1c/0x28 [<ffffffc0000bbad0>] ___might_sleep+0x120/0x198 [<ffffffc0006223e8>] rt_spin_lock+0x28/0x40 [<ffffffc000622b30>] __aarch64_insn_write+0x28/0x78 [<ffffffc000622e48>] aarch64_insn_patch_text_nosync+0x18/0x48 [<ffffffc000622ee8>] aarch64_insn_patch_text_cb+0x70/0xa0 [<ffffffc000622f40>] aarch64_insn_patch_text_sync+0x28/0x48 [<ffffffc0006236e0>] arch_arm_kprobe+0x38/0x48 [<ffffffc00010e6f4>] arm_kprobe+0x34/0x50 [<ffffffc000110374>] register_kprobe+0x4cc/0x5b8 [<ffffffbffc002038>] kprobe_init+0x38/0x7c [kprobe_example] [<ffffffc000084240>] do_one_initcall+0x90/0x1b0 [<ffffffc00061c498>] do_init_module+0x6c/0x1cc [<ffffffc0000fd0c0>] load_module+0x17f8/0x1db0 [<ffffffc0000fd8cc>] SyS_finit_module+0xb4/0xc8 Convert patch_lock to raw loc kto avoid this issue. Although the problem is found on rt kernel, the fix should be applicable to mainline kernel too. Signed-off-by: Yang Shi <yang.shi@linaro.org> --- arch/arm64/kernel/insn.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)