On Mon, 1 Feb 2021 at 10:54, Dietmar Eggemann <dietmar.eggem...@arm.com> wrote:
>
> On 22/01/2021 13:39, Valentin Schneider wrote:
>
> [...]
>
> > @@ -1705,7 +1702,7 @@ void sched_init_numa(void)
> > /* Compute default topology size */
> > for (i = 0; sched_domain_topology[i].mask; i++);
> >
> > - tl = kzalloc((i + level + 1) *
> > + tl = kzalloc((i + nr_levels) *
> > sizeof(struct sched_domain_topology_level),
> > GFP_KERNEL);
> > if (!tl)
> > return;
>
> This hunk creates issues during startup on my Arm64 juno board on
> tip/sched/core.
>
> ---8<---
>
> From: Dietmar Eggemann <dietmar.eggem...@arm.com>
> Date: Mon, 1 Feb 2021 09:58:04 +0100
> Subject: [PATCH] sched/topology: Fix sched_domain_topology_level alloc in
> sched_init_numa
>
> Commit "sched/topology: Make sched_init_numa() use a set for the
> deduplicating sort" allocates 'i + nr_levels (level)' instead of
> 'i + nr_levels + 1' sched_domain_topology_level.
>
> This led to an Oops (on Arm64 juno with CONFIG_SCHED_DEBUG):
>
> sched_init_domains
> build_sched_domains()
> __free_domain_allocs()
> __sdt_free() {
> ...
> for_each_sd_topology(tl)
> ...
> sd = *per_cpu_ptr(sdd->sd, j); <--
> ...
> }
>
> Signed-off-by: Dietmar Eggemann <dietmar.eggem...@arm.com>
Same crash happens for me on hikey and db845c. This fixes the problem
Tested-by: Vincent Guittot <vincent.guit...@linaro.org>
> ---
>
> ./scripts/decode_stacktrace.sh ./vmlinux < input.log
>
> [ 0.495693] Internal error: Oops: 96000005 [#1] PREEMPT SMP
> [ 0.501280] Modules linked in:
> [ 0.504342] CPU: 0 PID: 1 Comm: swapper/0 Not tainted
> 5.11.0-rc2-00025-g7a976f77bb96 #95
> [ 0.512455] Hardware name: ARM Juno development board (r0) (DT)
> [ 0.518386] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO BTYPE=--)
> [ 0.524409] pc : build_sched_domains (kernel/sched/topology.c:1872
> kernel/sched/topology.c:1288 kernel/sched/topology.c:2120)
> [ 0.529132] lr : build_sched_domains (kernel/sched/topology.c:1868
> kernel/sched/topology.c:1288 kernel/sched/topology.c:2120)
> [ 0.533847] sp : ffff800011efbd00
> [ 0.537165] x29: ffff800011efbd00 x28: ffff800011b69a38
> [ 0.542496] x27: 0000000000000000 x26: 0000000000000000
> [ 0.547827] x25: ffff000800191600 x24: 0000000000000000
> [ 0.553157] x23: ffff800011b69a40 x22: 0000000000000001
> [ 0.558487] x21: ffff000800056e00 x20: ffff00080016f380
> [ 0.563818] x19: ffff800011b6a410 x18: 0000000000000000
> [ 0.569149] x17: 0000000000000000 x16: 0000000000000000
> [ 0.574478] x15: 0000000000000030 x14: ffffffffffffffff
> [ 0.579809] x13: ffff800011b82d38 x12: 0000000000000189
> [ 0.585139] x11: 0000000000000083 x10: ffff800011bdad38
> [ 0.590469] x9 : 00000000fffff000 x8 : ffff800011b82d38
> [ 0.595800] x7 : 00000000000000e0 x6 : 000000000000003f
> [ 0.601130] x5 : 0000000000000000 x4 : 0000000000000000
> [ 0.606460] x3 : 0000000000000000 x2 : ffff80096d857000
> [ 0.611790] x1 : 0000000000000001 x0 : 0000000000000001
> [ 0.617120] Call trace:
> [ 0.619566] build_sched_domains (kernel/sched/topology.c:1872
> kernel/sched/topology.c:1288 kernel/sched/topology.c:2120)
> [ 0.623934] sched_init_domains (kernel/sched/topology.c:2194)
> [ 0.627954] sched_init_smp (kernel/sched/core.c:7727)
> [ 0.631629] kernel_init_freeable (init/main.c:1528)
> [ 0.635914] kernel_init (init/main.c:1417)
> [ 0.639416] ret_from_fork (arch/arm64/kernel/entry.S:959)
> [ 0.643008] Code: b4000360 93407f1b aa0003e1 f87b7ae2 (f8626821)
> All code
> ========
> 0: 60 (bad)
> 1: 03 00 add (%rax),%eax
> 3: b4 1b mov $0x1b,%ah
> 5: 7f 40 jg 0x47
> 7: 93 xchg %eax,%ebx
> 8: e1 03 loope 0xd
> a: 00 aa e2 7a 7b f8 add %ch,-0x784851e(%rdx)
> 10:* 21 68 62 and %ebp,0x62(%rax) <-- trapping
> instruction
> 13: f8 clc
>
> Code starting with the faulting instruction
> ===========================================
> 0: 21 68 62 and %ebp,0x62(%rax)
> 3: f8 clc
> [ 0.649129] ---[ end trace 4453f742a7781011 ]---
> [ 0.653772] Kernel panic - not syncing: Attempted to kill init!
> exitcode=0x0000000b
> [ 0.661449] SMP: stopping secondary CPUs
> [ 0.665389] ---[ end Kernel panic - not syncing: Attempted to kill init!
> exitcode=0x0000000b ]---
>
> kernel/sched/topology.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
> index bf5c9bd10bfe..09d35044bd88 100644
> --- a/kernel/sched/topology.c
> +++ b/kernel/sched/topology.c
> @@ -1702,7 +1702,7 @@ void sched_init_numa(void)
> /* Compute default topology size */
> for (i = 0; sched_domain_topology[i].mask; i++);
>
> - tl = kzalloc((i + nr_levels) *
> + tl = kzalloc((i + nr_levels + 1) *
> sizeof(struct sched_domain_topology_level),
> GFP_KERNEL);
> if (!tl)
> return;
> --
> 2.25.1
