From db01bd663f4e46479f2165f6b4b257a7785a5de8 Mon Sep 17 00:00:00 2001 From: Nianyao Tang Date: Thu, 19 Sep 2024 15:46:01 +0800 Subject: [PATCH] irqchip/gic-v3-its: Fix VSYNC referencing an unmapped VPE on GIC v4.1 mainline inclusion from mainline-v6.9-rc4 commit 80e9963fb3b5509dfcabe9652d56bf4b35542055 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IARQ2V Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=80e9963fb3b5509dfcabe9652d56bf4b35542055 --------------------------------------------------------------------------- As per the GICv4.1 spec (Arm IHI 0069H, 5.3.19): "A VMAPP with {V, Alloc}=={0, x} is self-synchronizing, This means the ITS command queue does not show the command as consumed until all of its effects are completed." Furthermore, VSYNC is allowed to deliver an SError when referencing a non existent VPE. By these definitions, a VMAPP followed by a VSYNC is a bug, as the later references a VPE that has been unmapped by the former. Fix it by eliding the VSYNC in this scenario. Fixes: 64edfaa9a234 ("irqchip/gic-v4.1: Implement the v4.1 flavour of VMAPP") Signed-off-by: Nianyao Tang Signed-off-by: Thomas Gleixner Reviewed-by: Marc Zyngier Reviewed-by: Zenghui Yu Link: https://lore.kernel.org/r/20240406022737.3898763-1-tangnianyao@huawei.com Signed-off-by: Zhou Wang --- drivers/irqchip/irq-gic-v3-its.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 2a284007f12a..ab92d8c02003 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -1040,6 +1040,7 @@ static struct its_vpe *its_build_vmapp_cmd(struct its_node *its, struct its_cmd_block *cmd, struct its_cmd_desc *desc) { + struct its_vpe *vpe = valid_vpe(its, desc->its_vmapp_cmd.vpe); unsigned long vpt_addr, vconf_addr; u64 target; bool alloc; @@ -1052,6 +1053,11 @@ static struct its_vpe *its_build_vmapp_cmd(struct its_node *its, if (is_v4_1(its)) { alloc = !atomic_dec_return(&desc->its_vmapp_cmd.vpe->vmapp_count); its_encode_alloc(cmd, alloc); + /* + * Unmapping a VPE is self-synchronizing on GICv4.1, + * no need to issue a VSYNC. + */ + vpe = NULL; } goto out; @@ -1081,7 +1087,7 @@ static struct its_vpe *its_build_vmapp_cmd(struct its_node *its, out: its_fixup_cmd(cmd); - return valid_vpe(its, desc->its_vmapp_cmd.vpe); + return vpe; } static struct its_vpe *its_build_vmapti_cmd(struct its_node *its, -- Gitee