Re: [PATCH 03/35] irqchip/gic-v3-its: Allow LPI invalidation via the DirectLPI interface
From: Zenghui Yu
Date: Thu Sep 26 2019 - 10:59:50 EST
Hi Marc,
I get one kernel panic with this patch on D05.
(I don't have the GICv4.1 board at the moment. I have to wait for the
appropriate HW to do more tests.)
On 2019/9/24 2:25, Marc Zyngier wrote:
We currently don't make much use of the DirectLPI feature, and it would
be beneficial to do this more, if only because it becomes a mandatory
feature for GICv4.1.
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
drivers/irqchip/irq-gic-v3-its.c | 51 +++++++++++++++++++++++---------
1 file changed, 37 insertions(+), 14 deletions(-)
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 58cb233cf138..c94eb287393b 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -175,6 +175,12 @@ static DEFINE_IDA(its_vpeid_ida);
#define gic_data_rdist_rd_base() (gic_data_rdist()->rd_base)
#define gic_data_rdist_vlpi_base() (gic_data_rdist_rd_base() + SZ_128K)
+static inline u32 its_get_event_id(struct irq_data *d)
+{
+ struct its_device *its_dev = irq_data_get_irq_chip_data(d);
+ return d->hwirq - its_dev->event_map.lpi_base;
+}
+
static struct its_collection *dev_event_to_col(struct its_device *its_dev,
u32 event)
{
@@ -183,6 +189,13 @@ static struct its_collection *dev_event_to_col(struct its_device *its_dev,
return its->collections + its_dev->event_map.col_map[event];
}
+static struct its_collection *irq_to_col(struct irq_data *d)
+{
+ struct its_device *its_dev = irq_data_get_irq_chip_data(d);
+
+ return dev_event_to_col(its_dev, its_get_event_id(d));
+}
+
irq_to_col uses device's event_map and col_map to get the target
collection, yes it works well with device's LPI.
But direct_lpi_inv also pass doorbells to it...
We don't allocate doorbells for any devices, instead for each vPE.
And see below,
static struct its_collection *valid_col(struct its_collection *col)
{
if (WARN_ON_ONCE(col->target_address & GENMASK_ULL(15, 0)))
@@ -1031,12 +1044,6 @@ static void its_send_vinvall(struct its_node *its, struct its_vpe *vpe)
* irqchip functions - assumes MSI, mostly.
*/
-static inline u32 its_get_event_id(struct irq_data *d)
-{
- struct its_device *its_dev = irq_data_get_irq_chip_data(d);
- return d->hwirq - its_dev->event_map.lpi_base;
-}
-
static void lpi_write_config(struct irq_data *d, u8 clr, u8 set)
{
irq_hw_number_t hwirq;
@@ -1081,12 +1088,28 @@ static void wait_for_syncr(void __iomem *rdbase)
cpu_relax();
}
+static void direct_lpi_inv(struct irq_data *d)
+{
+ struct its_collection *col;
+ void __iomem *rdbase;
+
+ /* Target the redistributor this LPI is currently routed to */
+ col = irq_to_col(d);
+ rdbase = per_cpu_ptr(gic_rdists->rdist, col->col_id)->rd_base;
+ gic_write_lpir(d->hwirq, rdbase + GICR_INVLPIR);
+
+ wait_for_syncr(rdbase);
+}
+
static void lpi_update_config(struct irq_data *d, u8 clr, u8 set)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
lpi_write_config(d, clr, set);
- its_send_inv(its_dev, its_get_event_id(d));
+ if (gic_rdists->has_direct_lpi && !irqd_is_forwarded_to_vcpu(d))
+ direct_lpi_inv(d);
+ else
+ its_send_inv(its_dev, its_get_event_id(d));
}
static void its_vlpi_set_doorbell(struct irq_data *d, bool enable)
@@ -2912,15 +2935,15 @@ static void its_vpe_send_cmd(struct its_vpe *vpe,
static void its_vpe_send_inv(struct irq_data *d)
{
- struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
-
if (gic_rdists->has_direct_lpi) {
- void __iomem *rdbase;
-
- rdbase = per_cpu_ptr(gic_rdists->rdist, vpe->col_idx)->rd_base;
- gic_write_lpir(vpe->vpe_db_lpi, rdbase + GICR_INVLPIR);
- wait_for_syncr(rdbase);
+ /*
+ * Don't mess about. Generating the invalidation is easily
+ * done by using the parent irq_data, just like below.
+ */
+ direct_lpi_inv(d->parent_data);
"GICv4-vpe"'s parent is "GICv3", not "ITS". What do we expect with
irq_data_get_irq_chip_data(parent's irq_data)?
I noticed it when running this series on D05 (with GICv4.0 and DirectLPI
support), panic call trace attached below.
I think we really need a fix here.
Thanks,
zenghui
} else {
+ struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
+
its_vpe_send_cmd(vpe, its_send_inv);
}
}
---8<
[ 2046.193227] Unable to handle kernel paging request at virtual address
0000002045fa4d92
[ 2046.201350] Mem abort info:
[ 2046.204132] ESR = 0x96000005
[ 2046.207174] Exception class = DABT (current EL), IL = 32 bits
[ 2046.213081] SET = 0, FnV = 0
[ 2046.216123] EA = 0, S1PTW = 0
[ 2046.219251] Data abort info:
[ 2046.222119] ISV = 0, ISS = 0x00000005
[ 2046.225942] CM = 0, WnR = 0
[ 2046.228898] user pgtable: 4k pages, 48-bit VAs, pgdp=0000001fa85d7000
[ 2046.235326] [0000002045fa4d92] pgd=0000001fb185d003, pud=0000000000000000
[ 2046.242103] Internal error: Oops: 96000005 [#1] PREEMPT SMP
[ 2046.247664] Modules linked in: openvswitch nsh nf_conncount nf_nat
nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ebtable_filter ebtables
ip6table_filter ip6_tables iptable_filter sunrpc vfat fat aes_ce_blk
crypto_simd cryptd aesel vhost_net tun vhost tap ip_tables ext4 mbcache
jbd2 sd_mod marvell hisi_sas_v2_hw hisi_sas_main ipmi_si libsas
scsi_transport_sas hns_mdio hnae br_netfilter bridge dm_mod stp llc nvme
nvme_core xt_sctp sctp libcrc32c nbd
[ 2046.307974] CPU: 3 PID: 15094 Comm: CPU 0/KVM Kdump: loaded Not
tainted 5.3.0gic-v4.1-devel+ #2
[ 2046.316658] Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.58
10/29/2018
[ 2046.323867] pstate: 60000085 (nZCv daIf -PAN -UAO)
[ 2046.328646] pc : direct_lpi_inv+0x7c/0xe0
[ 2046.332643] lr : its_vpe_send_inv.isra.24+0x50/0x60
[ 2046.337508] sp : ffff000034cab780
[ 2046.340810] x29: ffff000034cab780 x28: ffff000010e7c000
[ 2046.346110] x27: 0000000000000002 x26: ffff0000113718c0
[ 2046.351410] x25: ffff00001136f000 x24: ffff80af8a3f7420
[ 2046.356710] x23: 0000000000000001 x22: 0000000000000001
[ 2046.362010] x21: ffff80af95d96518 x20: ffff802fb78bf380
[ 2046.367309] x19: ffff80af95d96548 x18: 0000000000000000
[ 2046.372609] x17: 0000000000000000 x16: 0000000000000000
[ 2046.377908] x15: 0000000000000000 x14: 0000000000000000
[ 2046.383207] x13: 0000000000000000 x12: 0000000000000088
[ 2046.388506] x11: 0000000000000002 x10: ffff00001156a000
[ 2046.393805] x9 : 0000000000000000 x8 : ffff00001136f848
[ 2046.399105] x7 : ffff00001018c6a8 x6 : 0000001fba060000
[ 2046.404405] x5 : ffff000012c40000 x4 : 0000000045fa26c9
[ 2046.409704] x3 : ffff801fbb429800 x2 : 00000000000026c9
[ 2046.415004] x1 : ffff00001136f8a8 x0 : ffff000012163000
[ 2046.420303] Call trace:
[ 2046.422739] direct_lpi_inv+0x7c/0xe0
[ 2046.426388] its_vpe_send_inv.isra.24+0x50/0x60
[ 2046.430906] its_vpe_unmask_irq+0x34/0x40
[ 2046.434904] unmask_irq.part.5+0x30/0x50
[ 2046.438814] irq_enable+0x78/0x98
[ 2046.442116] __irq_startup+0x88/0x90
[ 2046.445680] irq_startup+0x7c/0x140
[ 2046.449156] __enable_irq+0x80/0x90
[ 2046.452632] enable_irq+0x58/0xb0
[ 2046.455934] its_make_vpe_non_resident+0xf0/0x108
[ 2046.460626] vgic_v4_put+0x64/0x70
[ 2046.464015] kvm_arch_vcpu_blocking+0x34/0x68
[ 2046.468360] kvm_vcpu_block+0x50/0x598
[ 2046.472097] kvm_handle_wfx+0x118/0x3d8
[ 2046.475920] handle_exit+0x14c/0x1c8
[ 2046.479484] kvm_arch_vcpu_ioctl_run+0x338/0xab8
[ 2046.484088] kvm_vcpu_ioctl+0x3c8/0xa60
[ 2046.487912] do_vfs_ioctl+0xc4/0x7f0
[ 2046.491475] ksys_ioctl+0x8c/0xa0
[ 2046.494778] __arm64_sys_ioctl+0x28/0x38
[ 2046.498689] el0_svc_common.constprop.0+0x80/0x1b8
[ 2046.503467] el0_svc_handler+0x34/0x90
[ 2046.507204] el0_svc+0x8/0xc
[ 2046.510076] Code: d0006f41 f940d865 9122a021 d000dee0 (786478c3)
[ 2046.516158] ---[ end trace f6392171e61487dc ]---
[ 2046.520763] Kernel panic - not syncing: Fatal exception
[ 2046.525976] SMP: stopping secondary CPUs
[ 2046.529913] Kernel Offset: disabled
[ 2046.533391] CPU features: 0x0002,20006008
[ 2046.537387] Memory Limit: none