Re: [PATCH v5 5/9] task_isolation: Add driver-specific hooks
From: Mark Rutland <mark.rutland@arm.com>
Date: 2020-12-02 14:19:17
Also in:
linux-api, linux-arch, linux-arm-kernel, lkml
On Mon, Nov 23, 2020 at 05:57:42PM +0000, Alex Belits wrote:
Some drivers don't call functions that call task_isolation_kernel_enter() in interrupt handlers. Call it directly.
I don't think putting this in drivers is the right approach. IIUC we only need to track user<->kernel transitions, and we can do that within the architectural entry code before we ever reach irqchip code. I suspect the current approacch is an artifact of that being difficult in the old structure of the arch code; recent rework should address that, and we can restruecture things further in future. Thanks, Mark.
quoted hunk ↗ jump to hunk
Signed-off-by: Alex Belits <redacted> --- drivers/irqchip/irq-armada-370-xp.c | 6 ++++++ drivers/irqchip/irq-gic-v3.c | 3 +++ drivers/irqchip/irq-gic.c | 3 +++ drivers/s390/cio/cio.c | 3 +++ 4 files changed, 15 insertions(+)diff --git a/drivers/irqchip/irq-armada-370-xp.c b/drivers/irqchip/irq-armada-370-xp.c index d7eb2e93db8f..4ac7babe1abe 100644 --- a/drivers/irqchip/irq-armada-370-xp.c +++ b/drivers/irqchip/irq-armada-370-xp.c@@ -29,6 +29,7 @@ #include <linux/slab.h> #include <linux/syscore_ops.h> #include <linux/msi.h> +#include <linux/isolation.h> #include <asm/mach/arch.h> #include <asm/exception.h> #include <asm/smp_plat.h>@@ -572,6 +573,7 @@ static const struct irq_domain_ops armada_370_xp_mpic_irq_ops = { static void armada_370_xp_handle_msi_irq(struct pt_regs *regs, bool is_chained) { u32 msimask, msinr; + int isol_entered = 0; msimask = readl_relaxed(per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS)@@ -588,6 +590,10 @@ static void armada_370_xp_handle_msi_irq(struct pt_regs *regs, bool is_chained) continue; if (is_chained) { + if (!isol_entered) { + task_isolation_kernel_enter(); + isol_entered = 1; + } irq = irq_find_mapping(armada_370_xp_msi_inner_domain, msinr - PCI_MSI_DOORBELL_START); generic_handle_irq(irq);diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index 16fecc0febe8..ded26dd4da0f 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c@@ -18,6 +18,7 @@ #include <linux/percpu.h> #include <linux/refcount.h> #include <linux/slab.h> +#include <linux/isolation.h> #include <linux/irqchip.h> #include <linux/irqchip/arm-gic-common.h>@@ -646,6 +647,8 @@ static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs { u32 irqnr; + task_isolation_kernel_enter(); + irqnr = gic_read_iar(); if (gic_supports_nmi() &&diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c index 6053245a4754..bb482b4ae218 100644 --- a/drivers/irqchip/irq-gic.c +++ b/drivers/irqchip/irq-gic.c@@ -35,6 +35,7 @@ #include <linux/interrupt.h> #include <linux/percpu.h> #include <linux/slab.h> +#include <linux/isolation.h> #include <linux/irqchip.h> #include <linux/irqchip/chained_irq.h> #include <linux/irqchip/arm-gic.h>@@ -337,6 +338,8 @@ static void __exception_irq_entry gic_handle_irq(struct pt_regs *regs) struct gic_chip_data *gic = &gic_data[0]; void __iomem *cpu_base = gic_data_cpu_base(gic); + task_isolation_kernel_enter(); + do { irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK); irqnr = irqstat & GICC_IAR_INT_ID_MASK;diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c index 6d716db2a46a..beab88881b6d 100644 --- a/drivers/s390/cio/cio.c +++ b/drivers/s390/cio/cio.c@@ -20,6 +20,7 @@ #include <linux/kernel_stat.h> #include <linux/interrupt.h> #include <linux/irq.h> +#include <linux/isolation.h> #include <asm/cio.h> #include <asm/delay.h> #include <asm/irq.h>@@ -584,6 +585,8 @@ void cio_tsch(struct subchannel *sch) struct irb *irb; int irq_context; + task_isolation_kernel_enter(); + irb = this_cpu_ptr(&cio_irb); /* Store interrupt response block to lowcore. */ if (tsch(sch->schid, irb) != 0)-- 2.20.1