Re: bisected: 4.18-rc* regression: x86-32 troubles (with timers?)

From: Daniel Borkmann
Date: Tue Jul 24 2018 - 14:40:39 EST


On 07/24/2018 06:47 AM, Meelis Roos wrote:
>>> Anyway, I started compile of v4.18-rc5 that was the latest I tested,
>>> with the commit in question reverted. Will see if I can test tomorrow
>>> morning. But I will leave tomorrow for a week and can only test further
>>> things if they happen to boot fine (no manual reboot possible for a
>>> week).
>>
>> Ok, thanks, please keep us posted on the outcome with the revert. Right
>> now I would doubt it's related resp. changes anything on the issue, but
>> lets see.
>
> v4.18-rc5 minus the patch in question worked fine on 2 bootups so it
> seems to be good.

And this was with CONFIG_BPF_JIT_ALWAYS_ON=y, correct? Could you try the
same with this below applied:

diff --git a/arch/x86/net/bpf_jit_comp32.c b/arch/x86/net/bpf_jit_comp32.c
index 5579987..313c983 100644
--- a/arch/x86/net/bpf_jit_comp32.c
+++ b/arch/x86/net/bpf_jit_comp32.c
@@ -175,7 +175,7 @@ static const u8 bpf2ia32[][2] = {
#define SCRATCH_SIZE 96

/* Total stack size used in JITed code */
-#define _STACK_SIZE (stack_depth + SCRATCH_SIZE)
+#define _STACK_SIZE (stack_depth + SCRATCH_SIZE + 4)

#define STACK_SIZE ALIGN(_STACK_SIZE, STACK_ALIGNMENT)


Thanks,
Daniel