Re: [PATCH] irqchip/gic-v4.1: Use GFP_ATOMIC flag in allocate_vpe_l1_table()
On Tue, 30 Jun 2020 21:37:46 +0800, Zenghui Yu wrote: > Booting the latest kernel with DEBUG_ATOMIC_SLEEP=y on a GICv4.1 enabled > box, I get the following kernel splat: > > [0.053766] BUG: sleeping function called from invalid context at > mm/slab.h:567 > [0.053767] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 0, > name: swapper/1 > [0.053769] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.8.0-rc3+ #23 > [0.053770] Call trace: > [0.053774] dump_backtrace+0x0/0x218 > [0.053775] show_stack+0x2c/0x38 > [0.053777] dump_stack+0xc4/0x10c > [0.053779] ___might_sleep+0xfc/0x140 > [0.053780] __might_sleep+0x58/0x90 > [0.053782] slab_pre_alloc_hook+0x7c/0x90 > [0.053783] kmem_cache_alloc_trace+0x60/0x2f0 > [0.053785] its_cpu_init+0x6f4/0xe40 > [0.053786] gic_starting_cpu+0x24/0x38 > [0.053788] cpuhp_invoke_callback+0xa0/0x710 > [0.053789] notify_cpu_starting+0xcc/0xd8 > [0.053790] secondary_start_kernel+0x148/0x200 > > [...] Applied to irq/irqchip-next, thanks! [1/1] irqchip/gic-v4.1: Use GFP_ATOMIC flag in allocate_vpe_l1_table() commit: d1bd7e0ba533a2a6f313579ec9b504f6614c35c4 Cheers, M. -- Without deviation from the norm, progress is not possible.
Re: [PATCH] irqchip/gic-v4.1: Use GFP_ATOMIC flag in allocate_vpe_l1_table()
Hi Zenghui,
On 2020-07-27 04:50, Zenghui Yu wrote:
Hi Marc,
On 2020/6/30 21:37, Zenghui Yu wrote:
Booting the latest kernel with DEBUG_ATOMIC_SLEEP=y on a GICv4.1
enabled
box, I get the following kernel splat:
[0.053766] BUG: sleeping function called from invalid context at
mm/slab.h:567
[0.053767] in_atomic(): 1, irqs_disabled(): 128, non_block: 0,
pid: 0, name: swapper/1
[0.053769] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.8.0-rc3+
#23
[0.053770] Call trace:
[0.053774] dump_backtrace+0x0/0x218
[0.053775] show_stack+0x2c/0x38
[0.053777] dump_stack+0xc4/0x10c
[0.053779] ___might_sleep+0xfc/0x140
[0.053780] __might_sleep+0x58/0x90
[0.053782] slab_pre_alloc_hook+0x7c/0x90
[0.053783] kmem_cache_alloc_trace+0x60/0x2f0
[0.053785] its_cpu_init+0x6f4/0xe40
[0.053786] gic_starting_cpu+0x24/0x38
[0.053788] cpuhp_invoke_callback+0xa0/0x710
[0.053789] notify_cpu_starting+0xcc/0xd8
[0.053790] secondary_start_kernel+0x148/0x200
# ./scripts/faddr2line vmlinux its_cpu_init+0x6f4/0xe40
its_cpu_init+0x6f4/0xe40:
allocate_vpe_l1_table at drivers/irqchip/irq-gic-v3-its.c:2818
(inlined by) its_cpu_init_lpis at
drivers/irqchip/irq-gic-v3-its.c:3138
(inlined by) its_cpu_init at drivers/irqchip/irq-gic-v3-its.c:5166
It turned out that we're allocating memory using GFP_KERNEL (may
sleep)
within the CPU hotplug notifier, which is indeed an atomic context.
Bad
thing may happen if we're playing on a system with more than a single
CommonLPIAff group. Avoid it by turning this into an atomic
allocation.
Fixes: 5e5168461c22 ("irqchip/gic-v4.1: VPE table (aka
GICR_VPROPBASER) allocation")
Signed-off-by: Zenghui Yu
---
drivers/irqchip/irq-gic-v3-its.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/irqchip/irq-gic-v3-its.c
b/drivers/irqchip/irq-gic-v3-its.c
index 6a5a87fc4601..b66eeca442c4 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -2814,7 +2814,7 @@ static int allocate_vpe_l1_table(void)
if (val & GICR_VPROPBASER_4_1_VALID)
goto out;
- gic_data_rdist()->vpe_table_mask = kzalloc(sizeof(cpumask_t),
GFP_KERNEL);
+ gic_data_rdist()->vpe_table_mask = kzalloc(sizeof(cpumask_t),
GFP_ATOMIC);
if (!gic_data_rdist()->vpe_table_mask)
return -ENOMEM;
@@ -2881,7 +2881,7 @@ static int allocate_vpe_l1_table(void)
pr_debug("np = %d, npg = %lld, psz = %d, epp = %d, esz = %d\n",
np, npg, psz, epp, esz);
- page = alloc_pages(GFP_KERNEL | __GFP_ZERO, get_order(np *
PAGE_SIZE));
+ page = alloc_pages(GFP_ATOMIC | __GFP_ZERO, get_order(np *
PAGE_SIZE));
if (!page)
return -ENOMEM;
Do you mind taking this patch into v5.9? Or please let me know if you
still have any concerns on it?
Oops, I seem to have dropped this one on the floor.
I've picked it up now.
Thanks for the heads up,
M.
--
Jazz is not dead. It just smells funny...
Re: [PATCH] irqchip/gic-v4.1: Use GFP_ATOMIC flag in allocate_vpe_l1_table()
Hi Marc,
On 2020/6/30 21:37, Zenghui Yu wrote:
Booting the latest kernel with DEBUG_ATOMIC_SLEEP=y on a GICv4.1 enabled
box, I get the following kernel splat:
[0.053766] BUG: sleeping function called from invalid context at
mm/slab.h:567
[0.053767] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 0,
name: swapper/1
[0.053769] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.8.0-rc3+ #23
[0.053770] Call trace:
[0.053774] dump_backtrace+0x0/0x218
[0.053775] show_stack+0x2c/0x38
[0.053777] dump_stack+0xc4/0x10c
[0.053779] ___might_sleep+0xfc/0x140
[0.053780] __might_sleep+0x58/0x90
[0.053782] slab_pre_alloc_hook+0x7c/0x90
[0.053783] kmem_cache_alloc_trace+0x60/0x2f0
[0.053785] its_cpu_init+0x6f4/0xe40
[0.053786] gic_starting_cpu+0x24/0x38
[0.053788] cpuhp_invoke_callback+0xa0/0x710
[0.053789] notify_cpu_starting+0xcc/0xd8
[0.053790] secondary_start_kernel+0x148/0x200
# ./scripts/faddr2line vmlinux its_cpu_init+0x6f4/0xe40
its_cpu_init+0x6f4/0xe40:
allocate_vpe_l1_table at drivers/irqchip/irq-gic-v3-its.c:2818
(inlined by) its_cpu_init_lpis at drivers/irqchip/irq-gic-v3-its.c:3138
(inlined by) its_cpu_init at drivers/irqchip/irq-gic-v3-its.c:5166
It turned out that we're allocating memory using GFP_KERNEL (may sleep)
within the CPU hotplug notifier, which is indeed an atomic context. Bad
thing may happen if we're playing on a system with more than a single
CommonLPIAff group. Avoid it by turning this into an atomic allocation.
Fixes: 5e5168461c22 ("irqchip/gic-v4.1: VPE table (aka GICR_VPROPBASER)
allocation")
Signed-off-by: Zenghui Yu
---
drivers/irqchip/irq-gic-v3-its.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 6a5a87fc4601..b66eeca442c4 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -2814,7 +2814,7 @@ static int allocate_vpe_l1_table(void)
if (val & GICR_VPROPBASER_4_1_VALID)
goto out;
- gic_data_rdist()->vpe_table_mask = kzalloc(sizeof(cpumask_t), GFP_KERNEL);
+ gic_data_rdist()->vpe_table_mask = kzalloc(sizeof(cpumask_t),
GFP_ATOMIC);
if (!gic_data_rdist()->vpe_table_mask)
return -ENOMEM;
@@ -2881,7 +2881,7 @@ static int allocate_vpe_l1_table(void)
pr_debug("np = %d, npg = %lld, psz = %d, epp = %d, esz = %d\n",
np, npg, psz, epp, esz);
- page = alloc_pages(GFP_KERNEL | __GFP_ZERO, get_order(np * PAGE_SIZE));
+ page = alloc_pages(GFP_ATOMIC | __GFP_ZERO, get_order(np * PAGE_SIZE));
if (!page)
return -ENOMEM;
Do you mind taking this patch into v5.9? Or please let me know if you
still have any concerns on it?
Thanks,
Zenghui
[PATCH] irqchip/gic-v4.1: Use GFP_ATOMIC flag in allocate_vpe_l1_table()
Booting the latest kernel with DEBUG_ATOMIC_SLEEP=y on a GICv4.1 enabled
box, I get the following kernel splat:
[0.053766] BUG: sleeping function called from invalid context at
mm/slab.h:567
[0.053767] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 0,
name: swapper/1
[0.053769] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.8.0-rc3+ #23
[0.053770] Call trace:
[0.053774] dump_backtrace+0x0/0x218
[0.053775] show_stack+0x2c/0x38
[0.053777] dump_stack+0xc4/0x10c
[0.053779] ___might_sleep+0xfc/0x140
[0.053780] __might_sleep+0x58/0x90
[0.053782] slab_pre_alloc_hook+0x7c/0x90
[0.053783] kmem_cache_alloc_trace+0x60/0x2f0
[0.053785] its_cpu_init+0x6f4/0xe40
[0.053786] gic_starting_cpu+0x24/0x38
[0.053788] cpuhp_invoke_callback+0xa0/0x710
[0.053789] notify_cpu_starting+0xcc/0xd8
[0.053790] secondary_start_kernel+0x148/0x200
# ./scripts/faddr2line vmlinux its_cpu_init+0x6f4/0xe40
its_cpu_init+0x6f4/0xe40:
allocate_vpe_l1_table at drivers/irqchip/irq-gic-v3-its.c:2818
(inlined by) its_cpu_init_lpis at drivers/irqchip/irq-gic-v3-its.c:3138
(inlined by) its_cpu_init at drivers/irqchip/irq-gic-v3-its.c:5166
It turned out that we're allocating memory using GFP_KERNEL (may sleep)
within the CPU hotplug notifier, which is indeed an atomic context. Bad
thing may happen if we're playing on a system with more than a single
CommonLPIAff group. Avoid it by turning this into an atomic allocation.
Fixes: 5e5168461c22 ("irqchip/gic-v4.1: VPE table (aka GICR_VPROPBASER)
allocation")
Signed-off-by: Zenghui Yu
---
drivers/irqchip/irq-gic-v3-its.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 6a5a87fc4601..b66eeca442c4 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -2814,7 +2814,7 @@ static int allocate_vpe_l1_table(void)
if (val & GICR_VPROPBASER_4_1_VALID)
goto out;
- gic_data_rdist()->vpe_table_mask = kzalloc(sizeof(cpumask_t),
GFP_KERNEL);
+ gic_data_rdist()->vpe_table_mask = kzalloc(sizeof(cpumask_t),
GFP_ATOMIC);
if (!gic_data_rdist()->vpe_table_mask)
return -ENOMEM;
@@ -2881,7 +2881,7 @@ static int allocate_vpe_l1_table(void)
pr_debug("np = %d, npg = %lld, psz = %d, epp = %d, esz = %d\n",
np, npg, psz, epp, esz);
- page = alloc_pages(GFP_KERNEL | __GFP_ZERO, get_order(np * PAGE_SIZE));
+ page = alloc_pages(GFP_ATOMIC | __GFP_ZERO, get_order(np * PAGE_SIZE));
if (!page)
return -ENOMEM;
--
2.19.1
