[PATCH dovetail v9 00/11] riscv: Add dovetail support

[PATCH dovetail v9 00/11] riscv: Add dovetail support

[Tobias Schaffner]

Hi all,

this series introduces initial support for Dovetail on RISC-V.

Feedback, suggestions, and especially reviews are very welcome.

Changes since v1:
 * Disable independent irq/softirq stack usage when pipelining
 * Drop KVM changes as long as they can not be properly tested

Changes since v2:
 * Rework trap handling

Changes since v3:
 * Included the IRQ pipelining patches to have all riscv specific
   patches included
 * Rebased to dovetail/v6.18.y-dovetail-rebase
 * Merged most of the fixes
 * Fixed IRQ Stack handling and enabled IRQ_STACKS again

Changes since v4:
 * Rebased to dovetail/v7.0.y-dovetail-rebase
 * Applied suggestions from the last patch set
 * Added starfive-visionfive2 board support
 * Introduced raw console device based on sbi debug console
 * Reworked pipelined irq handling

Changes since v5:
 * Rebased to tip of dovetail/v7.0.y-dovetail-rebase
 * Applied suggestions from the last patch set
 * Use mark_trap_entry/exit_raw for kernel mode exception paths which
   use irq_nmi_entry/exit for now, as the nmi irq handlers expect hard
   irqs to stay off. This may be be subject to further optimization at
   a later stage, but I do not see any negative impact latency wise in
   my tests.

Changes since v6:
Address the review comments from the last patch set:
 * Keep the virtual irq state in sync with the hard irq state in trap
   handlers
 * Fix irq_nesting imbalance when running with disabled IRQ_STACKS

Changes since v7:
 * Simplify Trap handling
 * Rebase to wip/flo/v7.1-dovetail-rebase

Changes since v8:
 * Further simplify trap handling adressing Florians suggestions and
   recent fixes to irq-entry-common

Best,
Tobias

Tobias Schaffner (11):
  riscv: introduce raw console device
  riscv: irq_pipeline: add IRQ pipelining core
  irqchip/riscv-aplic-direct: enable pipelined interrupt control
  irqchip/irq-riscv-aplic-msi: enable pipelined interrupt control
  irqchip/irq-riscv-imsic-platform: enable pipelined interrupt control
  irqchip/irq-riscv-intc: enable pipelined interrupt control
  irqchip/irq-sifive-plic: enable pipelined interrupt control
  clocksource/timer-riscv: irq_pipeline: enable pipelined clock events
  pinctrl: starfive: irq_pipeline: enable pipelined interrupt control
  PCI: plda: irq_pipeline: enable pipelined interrupt control
  riscv: dovetail: add core support

 arch/riscv/Kconfig                            |   3 +
 arch/riscv/include/asm/dovetail.h             |  24 +++
 arch/riscv/include/asm/entry-common.h         |   3 +-
 arch/riscv/include/asm/irq_pipeline.h         | 143 +++++++++++++
 arch/riscv/include/asm/irqflags.h             |  32 ++-
 arch/riscv/include/asm/mmu_context.h          |   2 +
 arch/riscv/include/asm/smp.h                  |  25 +++
 arch/riscv/include/asm/syscall.h              |   6 +
 arch/riscv/include/asm/thread_info.h          |  17 ++
 arch/riscv/kernel/Makefile                    |   2 +
 arch/riscv/kernel/irq_pipeline.c              |  26 +++
 arch/riscv/kernel/kernel_mode_vector.c        |   2 +-
 arch/riscv/kernel/raw_printk.c                |  33 +++
 arch/riscv/kernel/sbi-ipi.c                   |  12 +-
 arch/riscv/kernel/smp.c                       |  56 +++--
 arch/riscv/kernel/smpboot.c                   |   2 +-
 arch/riscv/kernel/traps.c                     | 199 +++++++++++++++---
 arch/riscv/mm/context.c                       |  20 +-
 arch/riscv/mm/fault.c                         |   8 +-
 drivers/clocksource/timer-riscv.c             |  11 +-
 drivers/irqchip/irq-riscv-aplic-direct.c      |   3 +-
 drivers/irqchip/irq-riscv-aplic-msi.c         |   3 +-
 drivers/irqchip/irq-riscv-imsic-platform.c    |   4 +-
 drivers/irqchip/irq-riscv-intc.c              |   2 +
 drivers/irqchip/irq-sifive-plic.c             |  10 +-
 drivers/pci/controller/plda/pcie-plda-host.c  |   2 +
 .../starfive/pinctrl-starfive-jh7110.c        |   2 +-
 .../starfive/pinctrl-starfive-jh7110.h        |   2 +-
 28 files changed, 577 insertions(+), 77 deletions(-)
 create mode 100644 arch/riscv/include/asm/dovetail.h
 create mode 100644 arch/riscv/include/asm/irq_pipeline.h
 create mode 100644 arch/riscv/kernel/irq_pipeline.c
 create mode 100644 arch/riscv/kernel/raw_printk.c

-- 
2.43.0

[PATCH dovetail v9 01/11] riscv: introduce raw console device

[Tobias Schaffner]

Signed-off-by: Tobias Schaffner <tobias.schaffner@siemens.com>
Signed-off-by: Florian Bezdeka <florian.bezdeka@siemens.com>
---
 arch/riscv/kernel/Makefile     |  1 +
 arch/riscv/kernel/raw_printk.c | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+)
 create mode 100644 arch/riscv/kernel/raw_printk.c

diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
index cabb99cadfb6..4e310257499a 100644
--- a/arch/riscv/kernel/Makefile
+++ b/arch/riscv/kernel/Makefile
@@ -104,6 +104,7 @@ obj-$(CONFIG_RISCV_SBI)		+= sbi.o sbi_ecall.o
 ifeq ($(CONFIG_RISCV_SBI), y)
 obj-$(CONFIG_SMP)		+= sbi-ipi.o
 obj-$(CONFIG_SMP) += cpu_ops_sbi.o
+obj-$(CONFIG_RAW_PRINTK)	+= raw_printk.o
 endif
 obj-$(CONFIG_HOTPLUG_CPU)	+= cpu-hotplug.o
 obj-$(CONFIG_PARAVIRT)		+= paravirt.o
diff --git a/arch/riscv/kernel/raw_printk.c b/arch/riscv/kernel/raw_printk.c
new file mode 100644
index 000000000000..aa2f287daa29
--- /dev/null
+++ b/arch/riscv/kernel/raw_printk.c
@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Raw console device for RISC-V using SBI debug console (DBCN).
+ *
+ * Copyright (C) 2026 Siemens AG
+ * Author:       Tobias Schaffner <tobias.schaffner@siemens.com>.
+ */
+
+#include <linux/kernel.h>
+#include <linux/console.h>
+#include <linux/init.h>
+#include <asm/sbi.h>
+
+static void raw_console_write(struct console *co,
+			      const char *s, unsigned int count)
+{
+	sbi_debug_console_write(s, count);
+}
+
+static struct console raw_console = {
+	.name		= "rawcon",
+	.write_raw	= raw_console_write,
+	.flags		= CON_PRINTBUFFER | CON_ENABLED,
+	.index		= -1,
+};
+
+static int __init raw_console_init(void)
+{
+	register_console(&raw_console);
+
+	return 0;
+}
+console_initcall(raw_console_init);
-- 
2.43.0

[PATCH dovetail v9 02/11] riscv: irq_pipeline: add IRQ pipelining core

[Tobias Schaffner]

This patchset integrates IRQ pipelining into the RISC-V architecture,
bringing it in line with the Dovetail/IRQ pipeline model used on other
architectures. It adds the core pipelining infrastructure and adapts
low-level primitives to cleanly separate in-band and out-of-band
interrupt handling.

Signed-off-by: Tobias Schaffner <tobias.schaffner@siemens.com>
Co-authored-by: shannmu <shanmu1901@gmail.com>
Co-authored-by: Philippe Gerum <rpm@xenomai.org>
---
 arch/riscv/Kconfig                     |   1 +
 arch/riscv/include/asm/entry-common.h  |   3 +-
 arch/riscv/include/asm/irq_pipeline.h  | 143 +++++++++++++++++++++++++
 arch/riscv/include/asm/irqflags.h      |  32 ++++--
 arch/riscv/include/asm/smp.h           |  25 +++++
 arch/riscv/include/asm/thread_info.h   |   9 ++
 arch/riscv/kernel/Makefile             |   1 +
 arch/riscv/kernel/irq_pipeline.c       |  26 +++++
 arch/riscv/kernel/kernel_mode_vector.c |   2 +-
 arch/riscv/kernel/sbi-ipi.c            |  12 ++-
 arch/riscv/kernel/smp.c                |  56 ++++++----
 arch/riscv/kernel/smpboot.c            |   2 +-
 arch/riscv/kernel/traps.c              |  85 +++++++++++++++
 arch/riscv/mm/fault.c                  |   8 +-
 14 files changed, 370 insertions(+), 35 deletions(-)
 create mode 100644 arch/riscv/include/asm/irq_pipeline.h
 create mode 100644 arch/riscv/kernel/irq_pipeline.c

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index c5754942cf85..7c58654c4ece 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -150,6 +150,7 @@ config RISCV
 	select HAVE_ARCH_USERFAULTFD_MINOR if 64BIT && USERFAULTFD
 	select HAVE_ARCH_USERFAULTFD_WP if 64BIT && MMU && USERFAULTFD && RISCV_ISA_SVRSW60T59B
 	select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
+	select HAVE_IRQ_PIPELINE
 	select HAVE_ASM_MODVERSIONS
 	select HAVE_CONTEXT_TRACKING_USER
 	select HAVE_DEBUG_KMEMLEAK
diff --git a/arch/riscv/include/asm/entry-common.h b/arch/riscv/include/asm/entry-common.h
index 34ed149af5d1..28ea8090316d 100644
--- a/arch/riscv/include/asm/entry-common.h
+++ b/arch/riscv/include/asm/entry-common.h
@@ -22,7 +22,8 @@ static inline void arch_exit_to_user_mode_prepare(struct pt_regs *regs,
 
 #define arch_exit_to_user_mode_prepare arch_exit_to_user_mode_prepare
 
-void handle_page_fault(struct pt_regs *regs);
+struct irqentry_state;
+void handle_page_fault(struct pt_regs *regs, struct irqentry_state state);
 void handle_break(struct pt_regs *regs);
 
 #ifdef CONFIG_RISCV_MISALIGNED
diff --git a/arch/riscv/include/asm/irq_pipeline.h b/arch/riscv/include/asm/irq_pipeline.h
new file mode 100644
index 000000000000..d4d4b7e79c67
--- /dev/null
+++ b/arch/riscv/include/asm/irq_pipeline.h
@@ -0,0 +1,143 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * IRQ Pipelining adapted from the ARM version.
+ *
+ * Copyright (C) 2024-2026 Siemens AG
+ * Author:       Tobias Schaffner <tobias.schaffner@siemens.com>.
+ */
+
+#ifndef _ASM_RISCV_IRQ_PIPELINE_H
+#define _ASM_RISCV_IRQ_PIPELINE_H
+
+#ifdef CONFIG_IRQ_PIPELINE
+
+#include <asm/ptrace.h>
+#include <asm/smp.h>
+
+#define OOB_NR_IPI		3
+
+extern int ipi_virq_base;
+
+#define CALL_FUNCTION_OOB_IPI (ipi_virq_base + OOB_CALL_FUNCTION_IPI)
+#define RESCHEDULE_OOB_IPI (ipi_virq_base + OOB_RESCHEDULE_IPI)
+#define TIMER_OOB_IPI (ipi_virq_base + OOB_TIMER_IPI)
+
+/* NOTE: Any bit should be fine as long as we don't hit SR_SIE or SR_MIE. */
+#define IRQMASK_i_POS   31
+
+static inline notrace
+unsigned long arch_irqs_virtual_to_native_flags(int stalled)
+{
+	if (!stalled)
+		return SR_IE;
+	return 0;
+}
+
+static inline notrace
+unsigned long arch_irqs_native_to_virtual_flags(unsigned long flags)
+{
+	return (!!native_irqs_disabled_flags(flags)) << IRQMASK_i_POS;
+}
+
+static inline int arch_irqs_disabled_flags(unsigned long flags)
+{
+	return native_irqs_disabled_flags(flags);
+}
+
+static inline notrace void arch_local_irq_enable(void)
+{
+	barrier();
+	inband_irq_enable();
+}
+
+static inline notrace void arch_local_irq_disable(void)
+{
+	inband_irq_disable();
+	barrier();
+}
+
+static inline notrace unsigned long arch_local_save_flags(void)
+{
+	int stalled = inband_irqs_disabled();
+
+	barrier();
+	return arch_irqs_virtual_to_native_flags(stalled);
+}
+
+static inline notrace unsigned long arch_local_irq_save(void)
+{
+	int stalled = inband_irq_save();
+
+	barrier();
+	return arch_irqs_virtual_to_native_flags(stalled);
+}
+
+/* set interrupt enabled status */
+static inline void arch_local_irq_restore(unsigned long flags)
+{
+	inband_irq_restore(arch_irqs_disabled_flags(flags));
+	barrier();
+}
+
+static inline
+void arch_save_timer_regs(struct pt_regs *dst, struct pt_regs *src)
+{
+	dst->status = src->status;
+	dst->epc = src->epc;
+}
+
+#else /* !CONFIG_IRQ_PIPELINE */
+
+static inline unsigned long arch_local_irq_save(void)
+{
+	return native_irq_save();
+}
+
+static inline void arch_local_irq_enable(void)
+{
+	native_irq_enable();
+}
+
+static inline void arch_local_irq_disable(void)
+{
+	native_irq_disable();
+}
+
+static inline unsigned long arch_local_save_flags(void)
+{
+	return native_save_flags();
+}
+
+static inline void arch_local_irq_restore(unsigned long flags)
+{
+	native_irq_restore(flags);
+}
+
+static inline int arch_irqs_disabled_flags(unsigned long flags)
+{
+	return native_irqs_disabled_flags(flags);
+}
+
+#endif /* !CONFIG_IRQ_PIPELINE */
+
+/* test hardware interrupt enable bit */
+static inline int arch_irqs_disabled(void)
+{
+	return arch_irqs_disabled_flags(arch_local_save_flags());
+}
+
+struct pt_regs;
+
+extern void (*handle_arch_irq)(struct pt_regs *);
+
+static inline void arch_handle_irq_pipelined(struct pt_regs *regs)
+{
+	handle_arch_irq(regs);
+}
+
+static inline int arch_enable_oob_stage(void)
+{
+	return 0;
+}
+
+#endif /* _ASM_RISCV_IRQ_PIPELINE_H */
diff --git a/arch/riscv/include/asm/irqflags.h b/arch/riscv/include/asm/irqflags.h
index 6fd8cbfcfcc7..c3087b74752b 100644
--- a/arch/riscv/include/asm/irqflags.h
+++ b/arch/riscv/include/asm/irqflags.h
@@ -10,45 +10,57 @@
 #include <asm/csr.h>
 
 /* read interrupt enabled status */
-static inline unsigned long arch_local_save_flags(void)
+static inline unsigned long native_save_flags(void)
 {
-	return csr_read(CSR_STATUS);
+	return csr_read(CSR_STATUS) & SR_IE;
 }
 
 /* unconditionally enable interrupts */
-static inline void arch_local_irq_enable(void)
+static inline void native_irq_enable(void)
 {
 	csr_set(CSR_STATUS, SR_IE);
 }
 
 /* unconditionally disable interrupts */
-static inline void arch_local_irq_disable(void)
+static inline void native_irq_disable(void)
 {
 	csr_clear(CSR_STATUS, SR_IE);
 }
 
 /* get status and disable interrupts */
-static inline unsigned long arch_local_irq_save(void)
+static inline unsigned long native_irq_save(void)
 {
 	return csr_read_clear(CSR_STATUS, SR_IE);
 }
 
 /* test flags */
-static inline int arch_irqs_disabled_flags(unsigned long flags)
+static inline int native_irqs_disabled_flags(unsigned long flags)
 {
 	return !(flags & SR_IE);
 }
 
 /* test hardware interrupt enable bit */
-static inline int arch_irqs_disabled(void)
+static inline bool native_irqs_disabled(void)
 {
-	return arch_irqs_disabled_flags(arch_local_save_flags());
+	return native_irqs_disabled_flags(native_save_flags());
 }
 
 /* set interrupt enabled status */
-static inline void arch_local_irq_restore(unsigned long flags)
+static inline void native_irq_restore(unsigned long flags)
 {
-	csr_set(CSR_STATUS, flags & SR_IE);
+	if (flags & SR_IE)
+		csr_set(CSR_STATUS, SR_IE);
+	else
+		csr_clear(CSR_STATUS, SR_IE);
+}
+
+#include <asm/irq_pipeline.h>
+
+static inline void native_irq_sync(void)
+{
+	native_irq_enable();
+	asm volatile("nop" : : : "memory");
+	native_irq_disable();
 }
 
 #endif /* _ASM_RISCV_IRQFLAGS_H */
diff --git a/arch/riscv/include/asm/smp.h b/arch/riscv/include/asm/smp.h
index 0ecc67641b09..8a409484d002 100644
--- a/arch/riscv/include/asm/smp.h
+++ b/arch/riscv/include/asm/smp.h
@@ -15,6 +15,31 @@
 struct seq_file;
 extern unsigned long boot_cpu_hartid;
 
+#ifdef CONFIG_IRQ_PIPELINE
+extern int ipi_max;
+#define IRQ_RISCV_IPI_MAX ipi_max
+#else
+#define IRQ_RISCV_IPI_MAX BITS_PER_BYTE
+#endif
+
+enum ipi_message_type {
+	IPI_RESCHEDULE,
+	IPI_CALL_FUNC,
+	IPI_CPU_STOP,
+	IPI_CPU_CRASH_STOP,
+	IPI_IRQ_WORK,
+	IPI_TIMER,
+	IPI_CPU_BACKTRACE,
+	IPI_KGDB_ROUNDUP,
+#ifdef CONFIG_IRQ_PIPELINE
+	OOB_TIMER_IPI,
+	OOB_RESCHEDULE_IPI,
+	OOB_CALL_FUNCTION_IPI,
+#endif
+	IPI_MAX,
+
+};
+
 #ifdef CONFIG_SMP
 
 #include <linux/jump_label.h>
diff --git a/arch/riscv/include/asm/thread_info.h b/arch/riscv/include/asm/thread_info.h
index 55019fdfa9ec..8bfb02064f48 100644
--- a/arch/riscv/include/asm/thread_info.h
+++ b/arch/riscv/include/asm/thread_info.h
@@ -52,6 +52,10 @@
  */
 struct thread_info {
 	unsigned long		flags;		/* low level flags */
+#ifdef CONFIG_IRQ_PIPELINE
+	__u32			local_flags;	/* local (synchronous) flags */
+#define ti_local_flags(__ti)    ((__ti)->local_flags)
+#endif
 	int                     preempt_count;  /* 0=>preemptible, <0=>BUG */
 	/*
 	 * These stack pointers are overwritten on every system call or
@@ -124,4 +128,9 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
 
 #define _TIF_RISCV_V_DEFER_RESTORE	BIT(TIF_RISCV_V_DEFER_RESTORE)
 
+/*
+ * Local (synchronous) thread flags.
+ */
+#define _TLF_OOB		0x0001
+
 #endif /* _ASM_RISCV_THREAD_INFO_H */
diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
index 4e310257499a..fb51d1bc5e3a 100644
--- a/arch/riscv/kernel/Makefile
+++ b/arch/riscv/kernel/Makefile
@@ -93,6 +93,7 @@ obj-$(CONFIG_MODULES)		+= module.o
 obj-$(CONFIG_MODULE_SECTIONS)	+= module-sections.o
 
 obj-$(CONFIG_CPU_PM)		+= suspend_entry.o suspend.o
+obj-$(CONFIG_IRQ_PIPELINE)	+= irq_pipeline.o
 obj-$(CONFIG_HIBERNATION)	+= hibernate.o hibernate-asm.o
 
 obj-$(CONFIG_FUNCTION_TRACER)	+= mcount.o ftrace.o
diff --git a/arch/riscv/kernel/irq_pipeline.c b/arch/riscv/kernel/irq_pipeline.c
new file mode 100644
index 000000000000..a478e9c3b3a4
--- /dev/null
+++ b/arch/riscv/kernel/irq_pipeline.c
@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * IRQ Pipelining implementation adapted from the ARM version.
+ *
+ * Copyright (C) 2024-2026 Siemens AG
+ * Author:       Tobias Schaffner <tobias.schaffner@siemens.com>.
+ */
+#include <linux/irq.h>
+#include <linux/irq_pipeline.h>
+
+void arch_do_IRQ_pipelined(struct irq_desc *desc)
+{
+	struct pt_regs *regs = raw_cpu_ptr(&irq_pipeline.tick_regs);
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
+	irq_enter_rcu();
+	handle_irq_desc(desc);
+	irq_exit_rcu();
+
+	set_irq_regs(old_regs);
+}
+
+void __init arch_irq_pipeline_init(void)
+{
+	/* no per-arch init. */
+}
diff --git a/arch/riscv/kernel/kernel_mode_vector.c b/arch/riscv/kernel/kernel_mode_vector.c
index 99972a48e86b..c4444577449c 100644
--- a/arch/riscv/kernel/kernel_mode_vector.c
+++ b/arch/riscv/kernel/kernel_mode_vector.c
@@ -171,7 +171,7 @@ asmlinkage void riscv_v_context_nesting_end(struct pt_regs *regs)
 	struct __riscv_v_ext_state *vstate = &current->thread.kernel_vstate;
 	u32 depth;
 
-	WARN_ON(!irqs_disabled());
+	WARN_ON(!hard_irqs_disabled());
 
 	if (!riscv_preempt_v_started(current))
 		return;
diff --git a/arch/riscv/kernel/sbi-ipi.c b/arch/riscv/kernel/sbi-ipi.c
index 0cc5559c08d8..600e2b51f1de 100644
--- a/arch/riscv/kernel/sbi-ipi.c
+++ b/arch/riscv/kernel/sbi-ipi.c
@@ -57,7 +57,7 @@ void __init sbi_ipi_init(void)
 		return;
 	}
 
-	virq = ipi_mux_create(BITS_PER_BYTE, sbi_send_ipi);
+	virq = ipi_mux_create(IRQ_RISCV_IPI_MAX, sbi_send_ipi);
 	if (virq <= 0) {
 		pr_err("unable to create muxed IPIs\n");
 		irq_dispose_mapping(sbi_ipi_virq);
@@ -75,12 +75,18 @@ void __init sbi_ipi_init(void)
 			  "irqchip/sbi-ipi:starting",
 			  sbi_ipi_starting_cpu, NULL);
 
-	riscv_ipi_set_virq_range(virq, BITS_PER_BYTE);
+	riscv_ipi_set_virq_range(virq, IRQ_RISCV_IPI_MAX);
 	pr_info("providing IPIs using SBI IPI extension\n");
 
 	/*
 	 * Use the SBI remote fence extension to avoid
 	 * the extra context switch needed to handle IPIs.
+	 *
+	 * When the IRQ pipeline is enabled, avoid the SBI remote fence
+	 * extension because SBI rfence traps to M-mode via ecall.
+	 * Use the IPI-based fence path instead, which stays  entirely in
+	 * S-mode and can be preempted by OOB interrupts.
 	 */
-	static_branch_enable(&riscv_sbi_for_rfence);
+	if (!irqs_pipelined())
+		static_branch_enable(&riscv_sbi_for_rfence);
 }
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 5ed5095320e6..8f842aec1e0e 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -21,6 +21,7 @@
 #include <linux/seq_file.h>
 #include <linux/delay.h>
 #include <linux/irq.h>
+#include <linux/irq_pipeline.h>
 #include <linux/irq_work.h>
 #include <linux/nmi.h>
 
@@ -28,18 +29,6 @@
 #include <asm/cacheflush.h>
 #include <asm/cpu_ops.h>
 
-enum ipi_message_type {
-	IPI_RESCHEDULE,
-	IPI_CALL_FUNC,
-	IPI_CPU_STOP,
-	IPI_CPU_CRASH_STOP,
-	IPI_IRQ_WORK,
-	IPI_TIMER,
-	IPI_CPU_BACKTRACE,
-	IPI_KGDB_ROUNDUP,
-	IPI_MAX
-};
-
 static const char * const ipi_names[] = {
 	[IPI_RESCHEDULE]	= "Rescheduling interrupts",
 	[IPI_CALL_FUNC]		= "Function call interrupts",
@@ -49,6 +38,11 @@ static const char * const ipi_names[] = {
 	[IPI_TIMER]		= "Timer broadcast interrupts",
 	[IPI_CPU_BACKTRACE]     = "CPU backtrace interrupts",
 	[IPI_KGDB_ROUNDUP]	= "KGDB roundup interrupts",
+#ifdef CONFIG_IRQ_PIPELINE
+	[OOB_TIMER_IPI]		= "OOB timer interrupts",
+	[OOB_RESCHEDULE_IPI]	= "OOB reschedule interrupts",
+	[OOB_CALL_FUNCTION_IPI]	= "OOB call function interrupts",
+#endif
 };
 
 unsigned long __cpuid_to_hartid_map[NR_CPUS] __ro_after_init = {
@@ -63,11 +57,35 @@ void __init smp_setup_processor_id(void)
 	pr_info("Booting Linux on hartid %lu\n", boot_cpu_hartid);
 }
 
-static DEFINE_PER_CPU_READ_MOSTLY(int, ipi_dummy_dev);
-static int ipi_virq_base __ro_after_init;
+int ipi_virq_base __ro_after_init;
 static int nr_ipi __ro_after_init = IPI_MAX;
 static struct irq_desc *ipi_desc[IPI_MAX] __read_mostly;
 
+#ifdef CONFIG_IRQ_PIPELINE
+#define INBAND_IPI_MAX (IPI_MAX - OOB_NR_IPI)
+int ipi_max __ro_after_init = IPI_MAX;
+
+void irq_send_oob_ipi(unsigned int irq,
+		const struct cpumask *cpumask)
+{
+	unsigned int op = irq - ipi_virq_base;
+
+	if (WARN_ON(irq_pipeline_debug() &&
+		    (op < INBAND_IPI_MAX ||
+		     op >= IPI_MAX)))
+		return;
+
+	/* Init oob ipis at first involve*/
+	if (unlikely(ipi_desc[op] == NULL))
+		ipi_desc[op] = irq_to_desc(irq);
+
+	__ipi_send_mask(ipi_desc[op], cpumask);
+}
+EXPORT_SYMBOL_GPL(irq_send_oob_ipi);
+#else
+#define INBAND_IPI_MAX IPI_MAX
+#endif
+
 int riscv_hartid_to_cpuid(unsigned long hartid)
 {
 	int i;
@@ -95,7 +113,7 @@ static inline void ipi_cpu_crash_stop(unsigned int cpu, struct pt_regs *regs)
 
 	atomic_dec(&waiting_for_crash_ipi);
 
-	local_irq_disable();
+	local_irq_disable_full();
 
 #ifdef CONFIG_HOTPLUG_CPU
 	if (cpu_has_hotplug(cpu))
@@ -209,9 +227,11 @@ void riscv_ipi_set_virq_range(int virq, int nr)
 
 	/* Request IPIs */
 	for (i = 0; i < nr_ipi; i++) {
-		err = request_percpu_irq(ipi_virq_base + i, handle_IPI,
-					 ipi_names[i], &ipi_dummy_dev);
-		WARN_ON(err);
+		if (i < INBAND_IPI_MAX) {
+			err = request_percpu_irq(ipi_virq_base + i, handle_IPI,
+						 ipi_names[i], &irq_stat);
+			WARN_ON(err);
+		}
 
 		ipi_desc[i] = irq_to_desc(ipi_virq_base + i);
 		irq_set_status_flags(ipi_virq_base + i, IRQ_HIDDEN);
diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
index 8b628580fe11..3eda9cbb31c3 100644
--- a/arch/riscv/kernel/smpboot.c
+++ b/arch/riscv/kernel/smpboot.c
@@ -259,6 +259,6 @@ asmlinkage __visible void smp_callin(void)
 #ifndef CONFIG_HOTPLUG_PARALLEL
 	complete(&cpu_running);
 #endif
-	local_irq_enable();
+	local_irq_enable_full();
 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
 }
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
index 8c62c771a656..fe6c547c93e4 100644
--- a/arch/riscv/kernel/traps.c
+++ b/arch/riscv/kernel/traps.c
@@ -112,10 +112,32 @@ void die(struct pt_regs *regs, const char *str)
 		make_task_dead(SIGSEGV);
 }
 
+static __always_inline
+bool mark_trap_entry(struct pt_regs *regs)
+{
+	if (likely(running_inband())) {
+		if (user_mode(regs))
+			hard_cond_local_irq_enable();
+		return true;
+	}
+
+	return false;
+}
+
+static __always_inline
+void mark_trap_exit(struct pt_regs *regs)
+{
+	if (likely(running_inband()) && user_mode(regs))
+		hard_cond_local_irq_disable();
+}
+
 void do_trap(struct pt_regs *regs, int signo, int code, unsigned long addr)
 {
 	struct task_struct *tsk = current;
 
+	if (!mark_trap_entry(regs))
+		return;
+
 	if (show_unhandled_signals && unhandled_signal(tsk, signo)
 	    && printk_ratelimit()) {
 		pr_info("%s[%d]: unhandled signal %d code 0x%x at 0x" REG_FMT,
@@ -127,6 +149,8 @@ void do_trap(struct pt_regs *regs, int signo, int code, unsigned long addr)
 	}
 
 	force_sig_fault(signo, code, (void __user *)addr);
+
+	mark_trap_exit(regs);
 }
 
 static void do_trap_error(struct pt_regs *regs, int signo, int code,
@@ -421,6 +445,65 @@ asmlinkage __visible noinstr void do_page_fault(struct pt_regs *regs)
 }
 #endif
 
+#ifdef CONFIG_IRQ_PIPELINE
+
+extern void (*handle_arch_irq)(struct pt_regs *);
+
+static void noinstr handle_riscv_irq_pipelined(struct pt_regs *regs)
+{
+	struct pt_regs *old_regs = set_irq_regs(regs);
+	handle_arch_irq(regs);
+	set_irq_regs(old_regs);
+}
+
+DEFINE_PER_CPU(int, irq_nesting);
+
+static void noinstr handle_riscv_irq_pipelined_on_stack(struct pt_regs *regs)
+{
+	int nesting = this_cpu_inc_return(irq_nesting);
+
+	if (IS_ENABLED(CONFIG_IRQ_STACKS) && nesting == 1)
+		call_on_irq_stack(regs, handle_riscv_irq_pipelined);
+	else
+		handle_riscv_irq_pipelined(regs);
+	this_cpu_dec(irq_nesting);
+}
+
+asmlinkage void noinstr do_irq(struct pt_regs *regs)
+{
+	irqentry_state_t state;
+	struct irq_stage_data *prevd;
+
+	/* OOB fast path: Log the IRQ and return. */
+	if (unlikely(running_oob() || irqs_disabled())) {
+		instrumentation_begin();
+		prevd = handle_irq_pipelined_prepare(regs);
+		handle_riscv_irq_pipelined(regs);
+		handle_irq_pipelined_finish(prevd, regs);
+		if (running_inband() && user_mode(regs)) {
+			stall_inband_nocheck();
+			irqentry_exit_to_user_mode(regs);
+		}
+		instrumentation_end();
+		return;
+	}
+
+	/* Handle inband IRQ. */
+	state = irqentry_enter(regs);
+	instrumentation_begin();
+	prevd = handle_irq_pipelined_prepare(regs);
+	handle_riscv_irq_pipelined_on_stack(regs);
+	trace_hardirqs_on();
+	unstall_inband_nocheck();
+	handle_irq_pipelined_finish(prevd, regs);
+	stall_inband_nocheck();
+	trace_hardirqs_off();
+	instrumentation_end();
+	irqentry_exit(regs, state);
+}
+
+#else	/* !CONFIG_IRQ_PIPELINE */
+
 static void noinstr handle_riscv_irq(struct pt_regs *regs)
 {
 	struct pt_regs *old_regs;
@@ -444,6 +527,8 @@ asmlinkage void noinstr do_irq(struct pt_regs *regs)
 	irqentry_exit(regs, state);
 }
 
+#endif /* !CONFIG_IRQ_PIPELINE */
+
 #ifdef CONFIG_GENERIC_BUG
 int is_valid_bugaddr(unsigned long pc)
 {
diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index 04ed6f8acae4..c5709112c346 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -79,6 +79,7 @@ static void show_pte(unsigned long addr)
 static void die_kernel_fault(const char *msg, unsigned long addr,
 		struct pt_regs *regs)
 {
+	irq_pipeline_oops();
 	bust_spinlocks(1);
 
 	pr_alert("Unable to handle kernel %s at virtual address " REG_FMT "\n", msg,
@@ -275,7 +276,7 @@ static inline bool access_error(unsigned long cause, struct vm_area_struct *vma)
  * This routine handles page faults.  It determines the address and the
  * problem, and then passes it off to one of the appropriate routines.
  */
-void handle_page_fault(struct pt_regs *regs)
+void handle_page_fault(struct pt_regs *regs, irqentry_state_t state)
 {
 	struct task_struct *tsk;
 	struct vm_area_struct *vma;
@@ -315,8 +316,13 @@ void handle_page_fault(struct pt_regs *regs)
 	}
 
 	/* Enable interrupts if they were enabled in the parent context. */
+#ifdef CONFIG_IRQ_PIPELINE
+	if (state.stage_info != IRQENTRY_INBAND_STALLED)
+		local_irq_enable_full();
+#else
 	if (!regs_irqs_disabled(regs))
 		local_irq_enable();
+#endif
 
 	/*
 	 * If we're in an interrupt, have no user context, or are running
-- 
2.43.0

[PATCH dovetail v9 03/11] irqchip/riscv-aplic-direct: enable pipelined interrupt control

[Tobias Schaffner]

Signed-off-by: Tobias Schaffner <tobias.schaffner@siemens.com>
Signed-off-by: Florian Bezdeka <florian.bezdeka@siemens.com>
---
 drivers/irqchip/irq-riscv-aplic-direct.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-riscv-aplic-direct.c b/drivers/irqchip/irq-riscv-aplic-direct.c
index 5a9650225dd8..b5d7205e1055 100644
--- a/drivers/irqchip/irq-riscv-aplic-direct.c
+++ b/drivers/irqchip/irq-riscv-aplic-direct.c
@@ -89,7 +89,8 @@ static struct irq_chip aplic_direct_chip = {
 #endif
 	.flags		= IRQCHIP_SET_TYPE_MASKED |
 			  IRQCHIP_SKIP_SET_WAKE |
-			  IRQCHIP_MASK_ON_SUSPEND,
+			  IRQCHIP_MASK_ON_SUSPEND |
+			  IRQCHIP_PIPELINE_SAFE,
 };
 
 static int aplic_direct_irqdomain_translate(struct irq_domain *d, struct irq_fwspec *fwspec,
-- 
2.43.0

[PATCH dovetail v9 04/11] irqchip/irq-riscv-aplic-msi: enable pipelined interrupt control

[Tobias Schaffner]

Signed-off-by: Tobias Schaffner <tobias.schaffner@siemens.com>
Signed-off-by: Florian Bezdeka <florian.bezdeka@siemens.com>
---
 drivers/irqchip/irq-riscv-aplic-msi.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-riscv-aplic-msi.c b/drivers/irqchip/irq-riscv-aplic-msi.c
index fb8d1838609f..25de8929ea37 100644
--- a/drivers/irqchip/irq-riscv-aplic-msi.c
+++ b/drivers/irqchip/irq-riscv-aplic-msi.c
@@ -156,7 +156,8 @@ static const struct msi_domain_template aplic_msi_template = {
 		.irq_write_msi_msg	= aplic_msi_write_msg,
 		.flags			= IRQCHIP_SET_TYPE_MASKED |
 					  IRQCHIP_SKIP_SET_WAKE |
-					  IRQCHIP_MASK_ON_SUSPEND,
+					  IRQCHIP_MASK_ON_SUSPEND |
+					  IRQCHIP_PIPELINE_SAFE,
 	},
 
 	.ops = {
-- 
2.43.0

[PATCH dovetail v9 05/11] irqchip/irq-riscv-imsic-platform: enable pipelined interrupt control

[Tobias Schaffner]

Signed-off-by: Tobias Schaffner <tobias.schaffner@siemens.com>
Signed-off-by: Florian Bezdeka <florian.bezdeka@siemens.com>
---
 drivers/irqchip/irq-riscv-imsic-platform.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-riscv-imsic-platform.c b/drivers/irqchip/irq-riscv-imsic-platform.c
index 643c8e459611..0b0dafecbfff 100644
--- a/drivers/irqchip/irq-riscv-imsic-platform.c
+++ b/drivers/irqchip/irq-riscv-imsic-platform.c
@@ -219,7 +219,9 @@ static struct irq_chip imsic_irq_base_chip = {
 	.irq_retrigger			= imsic_irq_retrigger,
 	.irq_ack			= imsic_irq_ack,
 	.irq_compose_msi_msg		= imsic_irq_compose_msg,
-	.flags				= IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND,
+	.flags				= IRQCHIP_SKIP_SET_WAKE |
+					  IRQCHIP_MASK_ON_SUSPEND |
+					  IRQCHIP_PIPELINE_SAFE,
 };
 
 static int imsic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
-- 
2.43.0

[PATCH dovetail v9 06/11] irqchip/irq-riscv-intc: enable pipelined interrupt control

[Tobias Schaffner]

Signed-off-by: Tobias Schaffner <tobias.schaffner@siemens.com>
Signed-off-by: Florian Bezdeka <florian.bezdeka@siemens.com>
---
 drivers/irqchip/irq-riscv-intc.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/irqchip/irq-riscv-intc.c b/drivers/irqchip/irq-riscv-intc.c
index 84418dbd5a27..855ce8dde27a 100644
--- a/drivers/irqchip/irq-riscv-intc.c
+++ b/drivers/irqchip/irq-riscv-intc.c
@@ -111,6 +111,7 @@ static struct irq_chip riscv_intc_chip = {
 	.irq_mask = riscv_intc_irq_mask,
 	.irq_unmask = riscv_intc_irq_unmask,
 	.irq_eoi = riscv_intc_irq_eoi,
+	.flags = IRQCHIP_PIPELINE_SAFE,
 };
 
 static struct irq_chip andes_intc_chip = {
@@ -118,6 +119,7 @@ static struct irq_chip andes_intc_chip = {
 	.irq_mask	= andes_intc_irq_mask,
 	.irq_unmask	= andes_intc_irq_unmask,
 	.irq_eoi	= riscv_intc_irq_eoi,
+	.flags		= IRQCHIP_PIPELINE_SAFE,
 };
 
 static int riscv_intc_domain_map(struct irq_domain *d, unsigned int irq,
-- 
2.43.0

[PATCH dovetail v9 07/11] irqchip/irq-sifive-plic: enable pipelined interrupt control

[Tobias Schaffner]

Signed-off-by: Tobias Schaffner <tobias.schaffner@siemens.com>
Signed-off-by: Florian Bezdeka <florian.bezdeka@siemens.com>
---
 drivers/irqchip/irq-sifive-plic.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
index 5b0dac104814..e9ea0c86366e 100644
--- a/drivers/irqchip/irq-sifive-plic.c
+++ b/drivers/irqchip/irq-sifive-plic.c
@@ -88,7 +88,7 @@ struct plic_handler {
 	 * Protect mask operations on the registers given that we can't
 	 * assume atomic memory operations work on them.
 	 */
-	raw_spinlock_t		enable_lock;
+	hard_spinlock_t		enable_lock;
 	void __iomem		*enable_base;
 	u32			*enable_save;
 	struct plic_priv	*priv;
@@ -227,7 +227,8 @@ static struct irq_chip plic_edge_chip = {
 #endif
 	.irq_set_type	= plic_irq_set_type,
 	.flags		= IRQCHIP_SKIP_SET_WAKE |
-			  IRQCHIP_AFFINITY_PRE_STARTUP,
+			  IRQCHIP_AFFINITY_PRE_STARTUP |
+			  IRQCHIP_PIPELINE_SAFE,
 };
 
 static struct irq_chip plic_chip = {
@@ -242,7 +243,8 @@ static struct irq_chip plic_chip = {
 #endif
 	.irq_set_type	= plic_irq_set_type,
 	.flags		= IRQCHIP_SKIP_SET_WAKE |
-			  IRQCHIP_AFFINITY_PRE_STARTUP,
+			  IRQCHIP_AFFINITY_PRE_STARTUP |
+			  IRQCHIP_PIPELINE_SAFE,
 };
 
 static int plic_irq_set_type(struct irq_data *d, unsigned int type)
@@ -444,7 +446,7 @@ static irq_hw_number_t cp100_get_hwirq(struct plic_handler *handler, void __iome
 	u32 iso_mask;
 	int i;
 
-	guard(raw_spinlock)(&handler->enable_lock);
+	guard(hard_spinlock)(&handler->enable_lock);
 
 	/* Existing enable state is already cached in enable_save */
 	iso_mask = cp100_isolate_pending_irq(nr_irq_groups, handler);
-- 
2.43.0

[PATCH dovetail v9 08/11] clocksource/timer-riscv: irq_pipeline: enable pipelined clock events

[Tobias Schaffner]

Signed-off-by: Tobias Schaffner <tobias.schaffner@siemens.com>
Signed-off-by: Florian Bezdeka <florian.bezdeka@siemens.com>
---
 drivers/clocksource/timer-riscv.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c
index cfc4d83c42c0..fceebef28978 100644
--- a/drivers/clocksource/timer-riscv.c
+++ b/drivers/clocksource/timer-riscv.c
@@ -71,7 +71,8 @@ static int riscv_clock_shutdown(struct clock_event_device *evt)
 static unsigned int riscv_clock_event_irq;
 static DEFINE_PER_CPU(struct clock_event_device, riscv_clock_event) = {
 	.name			= "riscv_timer_clockevent",
-	.features		= CLOCK_EVT_FEAT_ONESHOT,
+	.features		= CLOCK_EVT_FEAT_ONESHOT |
+				  CLOCK_EVT_FEAT_PIPELINE,
 	.rating			= 100,
 	.set_next_event		= riscv_clock_next_event,
 	.set_state_shutdown	= riscv_clock_shutdown,
@@ -150,7 +151,7 @@ static irqreturn_t riscv_timer_interrupt(int irq, void *dev_id)
 	struct clock_event_device *evdev = this_cpu_ptr(&riscv_clock_event);
 
 	riscv_clock_event_stop();
-	evdev->event_handler(evdev);
+	clockevents_handle_event(evdev);
 
 	return IRQ_HANDLED;
 }
@@ -182,9 +183,9 @@ static int __init riscv_timer_init_common(void)
 
 	sched_clock_register(riscv_sched_clock, 64, riscv_timebase);
 
-	error = request_percpu_irq(riscv_clock_event_irq,
-				    riscv_timer_interrupt,
-				    "riscv-timer", &riscv_clock_event);
+	error = request_percpu_irq_affinity_flags(riscv_clock_event_irq,
+				     riscv_timer_interrupt, IRQF_TIMER,
+				     "riscv-timer", NULL, &riscv_clock_event);
 	if (error) {
 		pr_err("registering percpu irq failed [%d]\n", error);
 		return error;
-- 
2.43.0

[PATCH dovetail v9 09/11] pinctrl: starfive: irq_pipeline: enable pipelined interrupt control

[Tobias Schaffner]

Signed-off-by: Tobias Schaffner <tobias.schaffner@siemens.com>
Signed-off-by: Florian Bezdeka <florian.bezdeka@siemens.com>
---
 drivers/pinctrl/starfive/pinctrl-starfive-jh7110.c | 2 +-
 drivers/pinctrl/starfive/pinctrl-starfive-jh7110.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pinctrl/starfive/pinctrl-starfive-jh7110.c b/drivers/pinctrl/starfive/pinctrl-starfive-jh7110.c
index e44480e71ea8..88c8940fd975 100644
--- a/drivers/pinctrl/starfive/pinctrl-starfive-jh7110.c
+++ b/drivers/pinctrl/starfive/pinctrl-starfive-jh7110.c
@@ -829,7 +829,7 @@ static struct irq_chip jh7110_irq_chip = {
 	.irq_mask_ack = jh7110_irq_mask_ack,
 	.irq_unmask   = jh7110_irq_unmask,
 	.irq_set_type = jh7110_irq_set_type,
-	.flags	      = IRQCHIP_IMMUTABLE | IRQCHIP_SET_TYPE_MASKED,
+	.flags	      = IRQCHIP_IMMUTABLE | IRQCHIP_SET_TYPE_MASKED | IRQCHIP_PIPELINE_SAFE,
 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
 };
 
diff --git a/drivers/pinctrl/starfive/pinctrl-starfive-jh7110.h b/drivers/pinctrl/starfive/pinctrl-starfive-jh7110.h
index 2da2d6858008..959578765cba 100644
--- a/drivers/pinctrl/starfive/pinctrl-starfive-jh7110.h
+++ b/drivers/pinctrl/starfive/pinctrl-starfive-jh7110.h
@@ -15,7 +15,7 @@ struct jh7110_pinctrl {
 	struct device *dev;
 	struct gpio_chip gc;
 	struct pinctrl_gpio_range gpios;
-	raw_spinlock_t lock;
+	hard_spinlock_t lock;
 	void __iomem *base;
 	struct pinctrl_dev *pctl;
 	/* register read/write mutex */
-- 
2.43.0

[PATCH dovetail v9 10/11] PCI: plda: irq_pipeline: enable pipelined interrupt control

[Tobias Schaffner]

Signed-off-by: Tobias Schaffner <tobias.schaffner@siemens.com>
Signed-off-by: Florian Bezdeka <florian.bezdeka@siemens.com>
---
 drivers/pci/controller/plda/pcie-plda-host.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/pci/controller/plda/pcie-plda-host.c b/drivers/pci/controller/plda/pcie-plda-host.c
index 3c2f68383010..8f0fda4b9421 100644
--- a/drivers/pci/controller/plda/pcie-plda-host.c
+++ b/drivers/pci/controller/plda/pcie-plda-host.c
@@ -244,6 +244,7 @@ static struct irq_chip plda_intx_irq_chip = {
 	.irq_ack = plda_ack_intx_irq,
 	.irq_mask = plda_mask_intx_irq,
 	.irq_unmask = plda_unmask_intx_irq,
+	.flags = IRQCHIP_PIPELINE_SAFE,
 };
 
 static int plda_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
@@ -358,6 +359,7 @@ static struct irq_chip plda_event_irq_chip = {
 	.irq_ack = plda_ack_event_irq,
 	.irq_mask = plda_mask_event_irq,
 	.irq_unmask = plda_unmask_event_irq,
+	.flags = IRQCHIP_PIPELINE_SAFE,
 };
 
 static const struct plda_event_ops plda_event_ops = {
-- 
2.43.0

[PATCH dovetail v9 11/11] riscv: dovetail: add core support

[Tobias Schaffner]

Add Dovetail co-kernel support for RISC-V, including, irq pipeline
integration, out-of-band aware trap handling and memory management.

Signed-off-by: Tobias Schaffner <tobias.schaffner@siemens.com>
---
 arch/riscv/Kconfig                   |   2 +
 arch/riscv/include/asm/dovetail.h    |  24 ++++++
 arch/riscv/include/asm/mmu_context.h |   2 +
 arch/riscv/include/asm/syscall.h     |   6 ++
 arch/riscv/include/asm/thread_info.h |   8 ++
 arch/riscv/kernel/traps.c            | 114 +++++++++++++++++++++------
 arch/riscv/mm/context.c              |  20 ++++-
 7 files changed, 148 insertions(+), 28 deletions(-)
 create mode 100644 arch/riscv/include/asm/dovetail.h

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 7c58654c4ece..912aada80962 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -151,6 +151,7 @@ config RISCV
 	select HAVE_ARCH_USERFAULTFD_WP if 64BIT && MMU && USERFAULTFD && RISCV_ISA_SVRSW60T59B
 	select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
 	select HAVE_IRQ_PIPELINE
+	select HAVE_DOVETAIL
 	select HAVE_ASM_MODVERSIONS
 	select HAVE_CONTEXT_TRACKING_USER
 	select HAVE_DEBUG_KMEMLEAK
@@ -376,6 +377,7 @@ config AS_HAS_OPTION_ARCH
 
 source "arch/riscv/Kconfig.socs"
 source "arch/riscv/Kconfig.errata"
+source "kernel/Kconfig.dovetail"
 
 menu "Platform type"
 
diff --git a/arch/riscv/include/asm/dovetail.h b/arch/riscv/include/asm/dovetail.h
new file mode 100644
index 000000000000..e5a46cf1f67f
--- /dev/null
+++ b/arch/riscv/include/asm/dovetail.h
@@ -0,0 +1,24 @@
+/*
+* SPDX-License-Identifier: GPL-2.0
+*
+* Copyright (C) 2024-2026 Siemens AG
+* Author:       Tobias Schaffner <tobias.schaffner@siemens.com>.
+*/
+#ifndef _ASM_RISCV_DOVETAIL_H
+#define _ASM_RISCV_DOVETAIL_H
+
+#if !defined(__ASSEMBLY__)
+#ifdef CONFIG_DOVETAIL
+
+static inline void arch_dovetail_exec_prepare(void)
+{ }
+
+static inline void arch_dovetail_switch_prepare(bool leave_inband)
+{ }
+
+static inline void arch_dovetail_switch_finish(bool enter_inband)
+{ }
+
+#endif /* CONFIG_DOVETAIL */
+#endif /* !__ASSEMBLY__ */
+#endif /* _ASM_RISCV_DOVETAIL_H */
diff --git a/arch/riscv/include/asm/mmu_context.h b/arch/riscv/include/asm/mmu_context.h
index dbf27a78df6c..a1ac9192d51c 100644
--- a/arch/riscv/include/asm/mmu_context.h
+++ b/arch/riscv/include/asm/mmu_context.h
@@ -15,6 +15,8 @@
 
 void switch_mm(struct mm_struct *prev, struct mm_struct *next,
 	struct task_struct *task);
+void switch_oob_mm(struct mm_struct *prev, struct mm_struct *next,
+	struct task_struct *task);
 
 #define activate_mm activate_mm
 static inline void activate_mm(struct mm_struct *prev,
diff --git a/arch/riscv/include/asm/syscall.h b/arch/riscv/include/asm/syscall.h
index 8067e666a4ca..12376b54268e 100644
--- a/arch/riscv/include/asm/syscall.h
+++ b/arch/riscv/include/asm/syscall.h
@@ -117,6 +117,12 @@ static inline bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs)
 	return false;
 }
 
+static inline unsigned long syscall_get_arg0(struct task_struct *task,
+					     struct pt_regs *regs)
+{
+	return regs->orig_a0;
+}
+
 asmlinkage long sys_riscv_flush_icache(uintptr_t, uintptr_t, uintptr_t);
 
 asmlinkage long sys_riscv_hwprobe(struct riscv_hwprobe *, size_t, size_t,
diff --git a/arch/riscv/include/asm/thread_info.h b/arch/riscv/include/asm/thread_info.h
index 8bfb02064f48..4934b7c8f1f1 100644
--- a/arch/riscv/include/asm/thread_info.h
+++ b/arch/riscv/include/asm/thread_info.h
@@ -41,6 +41,7 @@
 
 #include <asm/processor.h>
 #include <asm/csr.h>
+#include <dovetail/thread_info.h>
 
 /*
  * low level task data that entry.S needs immediate access to
@@ -80,6 +81,7 @@ struct thread_info {
 #ifdef CONFIG_RISCV_USER_CFI
 	struct cfi_state	user_cfi_state;
 #endif
+	struct oob_thread_state oob_state;      /* co-kernel thread state */
 };
 
 #ifdef CONFIG_SHADOW_CALL_STACK
@@ -123,6 +125,9 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
 
 #include <asm-generic/thread_info_tif.h>
 
+#define TIF_MAYDAY			14      /* emergency trap pending */
+#define _TIF_MAYDAY			(1 << TIF_MAYDAY)
+
 #define TIF_32BIT			16	/* compat-mode 32bit process */
 #define TIF_RISCV_V_DEFER_RESTORE	17	/* restore Vector before returning to user */
 
@@ -132,5 +137,8 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
  * Local (synchronous) thread flags.
  */
 #define _TLF_OOB		0x0001
+#define _TLF_DOVETAIL		0x0002
+#define _TLF_OFFSTAGE		0x0004
+#define _TLF_OOBTRAP		0x0008
 
 #endif /* _ASM_RISCV_THREAD_INFO_H */
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
index fe6c547c93e4..4dd7160e19c3 100644
--- a/arch/riscv/kernel/traps.c
+++ b/arch/riscv/kernel/traps.c
@@ -22,6 +22,8 @@
 #include <linux/irq.h>
 #include <linux/kexec.h>
 #include <linux/entry-common.h>
+#include <linux/audit.h>
+#include <linux/dovetail.h>
 
 #include <asm/asm-prototypes.h>
 #include <asm/bug.h>
@@ -115,18 +117,24 @@ void die(struct pt_regs *regs, const char *str)
 static __always_inline
 bool mark_trap_entry(struct pt_regs *regs)
 {
+	oob_trap_notify(regs->cause, regs);
+
 	if (likely(running_inband())) {
 		if (user_mode(regs))
 			hard_cond_local_irq_enable();
 		return true;
 	}
 
+	oob_trap_unwind(regs->cause, regs);
+
 	return false;
 }
 
 static __always_inline
 void mark_trap_exit(struct pt_regs *regs)
 {
+	oob_trap_unwind(regs->cause, regs);
+
 	if (likely(running_inband()) && user_mode(regs))
 		hard_cond_local_irq_disable();
 }
@@ -172,13 +180,19 @@ asmlinkage __visible __trap_section void name(struct pt_regs *regs)		\
 {										\
 	if (user_mode(regs)) {							\
 		irqentry_enter_from_user_mode(regs);				\
-		local_irq_enable();						\
-		do_trap_error(regs, signo, code, regs->epc, "Oops - " str);	\
-		local_irq_disable();						\
+		if (mark_trap_entry(regs)) {					\
+			local_irq_enable();					\
+			do_trap_error(regs, signo, code, regs->epc, "Oops - " str); \
+			local_irq_disable();					\
+			mark_trap_exit(regs);					\
+		}								\
 		irqentry_exit_to_user_mode(regs);				\
 	} else {								\
 		irqentry_state_t state = irqentry_nmi_enter(regs);		\
-		do_trap_error(regs, signo, code, regs->epc, "Oops - " str);	\
+		if (mark_trap_entry(regs)) {					\
+			do_trap_error(regs, signo, code, regs->epc, "Oops - " str); \
+			mark_trap_exit(regs);					\
+		}								\
 		irqentry_nmi_exit(regs, state);					\
 	}									\
 }
@@ -198,21 +212,26 @@ asmlinkage __visible __trap_section void do_trap_insn_illegal(struct pt_regs *re
 
 	if (user_mode(regs)) {
 		irqentry_enter_from_user_mode(regs);
-		local_irq_enable();
+		if (mark_trap_entry(regs)) {
+			local_irq_enable();
 
-		handled = riscv_v_first_use_handler(regs);
-		if (!handled)
-			do_trap_error(regs, SIGILL, ILL_ILLOPC, regs->epc,
-				      "Oops - illegal instruction");
+			handled = riscv_v_first_use_handler(regs);
 
-		local_irq_disable();
+			if (!handled)
+				do_trap_error(regs, SIGILL, ILL_ILLOPC, regs->epc,
+					      "Oops - illegal instruction");
+
+			local_irq_disable();
+			mark_trap_exit(regs);
+		}
 		irqentry_exit_to_user_mode(regs);
 	} else {
 		irqentry_state_t state = irqentry_nmi_enter(regs);
-
-		do_trap_error(regs, SIGILL, ILL_ILLOPC, regs->epc,
-			      "Oops - illegal instruction");
-
+		if (mark_trap_entry(regs)) {
+			do_trap_error(regs, SIGILL, ILL_ILLOPC, regs->epc,
+				      "Oops - illegal instruction");
+			mark_trap_exit(regs);
+		}
 		irqentry_nmi_exit(regs, state);
 	}
 }
@@ -244,17 +263,26 @@ static void do_trap_misaligned(struct pt_regs *regs, enum misaligned_access_type
 
 	if (user_mode(regs)) {
 		irqentry_enter_from_user_mode(regs);
+		if (!mark_trap_entry(regs))
+			goto out;
 		local_irq_enable();
 	} else {
 		state = irqentry_nmi_enter(regs);
+		if (!mark_trap_entry(regs))
+			goto out;
 	}
 
 	if (misaligned_handler[type].handler(regs))
 		do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->epc,
 			      misaligned_handler[type].type_str);
 
-	if (user_mode(regs)) {
+	if (user_mode(regs))
 		local_irq_disable();
+
+	mark_trap_exit(regs);
+
+out:
+	if (user_mode(regs)) {
 		irqentry_exit_to_user_mode(regs);
 	} else {
 		irqentry_nmi_exit(regs, state);
@@ -330,17 +358,21 @@ asmlinkage __visible __trap_section void do_trap_break(struct pt_regs *regs)
 {
 	if (user_mode(regs)) {
 		irqentry_enter_from_user_mode(regs);
-		local_irq_enable();
+		if (mark_trap_entry(regs)) {
+			local_irq_enable();
 
-		handle_break(regs);
+			handle_break(regs);
 
-		local_irq_disable();
+			local_irq_disable();
+			mark_trap_exit(regs);
+		}
 		irqentry_exit_to_user_mode(regs);
 	} else {
 		irqentry_state_t state = irqentry_nmi_enter(regs);
-
-		handle_break(regs);
-
+		if (mark_trap_entry(regs)) {
+			handle_break(regs);
+			mark_trap_exit(regs);
+		}
 		irqentry_nmi_exit(regs, state);
 	}
 }
@@ -359,6 +391,15 @@ void do_trap_ecall_u(struct pt_regs *regs)
 
 		syscall = syscall_enter_from_user_mode(regs, syscall);
 
+		if(dovetailing()) {
+			if (syscall == EXIT_SYSCALL_OOB) {
+				hard_local_irq_disable();
+				return;
+			}
+			if (syscall == EXIT_SYSCALL_TAIL)
+				goto done_inband;
+		}
+
 		add_random_kstack_offset();
 
 		if (syscall >= 0 && syscall < NR_syscalls) {
@@ -366,6 +407,13 @@ void do_trap_ecall_u(struct pt_regs *regs)
 			syscall_handler(regs, syscall);
 		}
 
+done_inband:
+		/*
+		 * Dovetail: balance audit entry that generic exit
+		 * skips for in_oob_syscall().
+		 */
+		if (dovetailing() && in_oob_syscall(regs))
+			audit_syscall_exit(regs);
 		syscall_exit_to_user_mode(regs);
 	} else {
 		irqentry_state_t state = irqentry_nmi_enter(regs);
@@ -420,11 +468,13 @@ asmlinkage __visible __trap_section void do_trap_software_check(struct pt_regs *
 {
 	if (user_mode(regs)) {
 		irqentry_enter_from_user_mode(regs);
+		if (mark_trap_entry(regs)) {
+			/* not a cfi violation, then merge into flow of unknown trap handler */
+			if (!handle_user_cfi_violation(regs))
+				do_trap_unknown(regs);
 
-		/* not a cfi violation, then merge into flow of unknown trap handler */
-		if (!handle_user_cfi_violation(regs))
-			do_trap_unknown(regs);
-
+			mark_trap_exit(regs);
+		}
 		irqentry_exit_to_user_mode(regs);
 	} else {
 		/* sw check exception coming from kernel is a bug in kernel */
@@ -437,10 +487,22 @@ asmlinkage __visible noinstr void do_page_fault(struct pt_regs *regs)
 {
 	irqentry_state_t state = irqentry_enter(regs);
 
-	handle_page_fault(regs);
+	mark_trap_entry(regs);
+
+	BUG_ON(dovetail_debug() && !running_inband());
+
+	if (!user_mode(regs))
+		hard_cond_local_irq_enable();
+
+	handle_page_fault(regs, state);
 
 	local_irq_disable();
 
+	mark_trap_exit(regs);
+
+	if (!user_mode(regs))
+		hard_cond_local_irq_disable();
+
 	irqentry_exit(regs, state);
 }
 #endif
diff --git a/arch/riscv/mm/context.c b/arch/riscv/mm/context.c
index 55c20ad1f744..8f38b4a5eb26 100644
--- a/arch/riscv/mm/context.c
+++ b/arch/riscv/mm/context.c
@@ -25,7 +25,7 @@ static unsigned long num_asids;
 
 static atomic_long_t current_version;
 
-static DEFINE_RAW_SPINLOCK(context_lock);
+static DEFINE_HARD_SPINLOCK(context_lock);
 static cpumask_t context_tlb_flush_pending;
 static unsigned long *context_asid_map;
 
@@ -315,7 +315,7 @@ static inline void flush_icache_deferred(struct mm_struct *mm, unsigned int cpu,
 #endif
 }
 
-void switch_mm(struct mm_struct *prev, struct mm_struct *next,
+static void do_switch_mm(struct mm_struct *prev, struct mm_struct *next,
 	struct task_struct *task)
 {
 	unsigned int cpu;
@@ -336,3 +336,19 @@ void switch_mm(struct mm_struct *prev, struct mm_struct *next,
 
 	flush_icache_deferred(next, cpu, task);
 }
+
+void switch_mm(struct mm_struct *prev, struct mm_struct *next,
+	struct task_struct *task)
+{
+	unsigned long flags;
+
+	protect_inband_mm(flags);
+	do_switch_mm(prev, next, task);
+	unprotect_inband_mm(flags);
+}
+
+void switch_oob_mm(struct mm_struct *prev, struct mm_struct *next,
+	struct task_struct *task)
+{
+	do_switch_mm(prev, next, task);
+}
-- 
2.43.0

Re: [PATCH dovetail v9 00/11] riscv: Add dovetail support

[Florian Bezdeka]

On Fri, 2026-07-03 at 17:27 +0200, Tobias Schaffner wrote:
> Hi all,
> 
> this series introduces initial support for Dovetail on RISC-V.
> 
> Feedback, suggestions, and especially reviews are very welcome.
> 
> Changes since v1:
>  * Disable independent irq/softirq stack usage when pipelining
>  * Drop KVM changes as long as they can not be properly tested
> 
> Changes since v2:
>  * Rework trap handling
> 
> Changes since v3:
>  * Included the IRQ pipelining patches to have all riscv specific
>    patches included
>  * Rebased to dovetail/v6.18.y-dovetail-rebase
>  * Merged most of the fixes
>  * Fixed IRQ Stack handling and enabled IRQ_STACKS again
> 
> Changes since v4:
>  * Rebased to dovetail/v7.0.y-dovetail-rebase
>  * Applied suggestions from the last patch set
>  * Added starfive-visionfive2 board support
>  * Introduced raw console device based on sbi debug console
>  * Reworked pipelined irq handling
> 
> Changes since v5:
>  * Rebased to tip of dovetail/v7.0.y-dovetail-rebase
>  * Applied suggestions from the last patch set
>  * Use mark_trap_entry/exit_raw for kernel mode exception paths which
>    use irq_nmi_entry/exit for now, as the nmi irq handlers expect hard
>    irqs to stay off. This may be be subject to further optimization at
>    a later stage, but I do not see any negative impact latency wise in
>    my tests.
> 
> Changes since v6:
> Address the review comments from the last patch set:
>  * Keep the virtual irq state in sync with the hard irq state in trap
>    handlers
>  * Fix irq_nesting imbalance when running with disabled IRQ_STACKS
> 
> Changes since v7:
>  * Simplify Trap handling
>  * Rebase to wip/flo/v7.1-dovetail-rebase
> 
> Changes since v8:
>  * Further simplify trap handling adressing Florians suggestions and
>    recent fixes to irq-entry-common

Minor:

 - Changelog in reverse order, newest first
 - Enumeration of changed patches, so we don't have to review all
   of them again.



Philippe, how do we proceed here? Do you want me to update the +riscv
branches that we have for 7.1 and than take over from there? Or should
we move it to the 7.2 cycle?

Same question for 7.1: How do we proceed as 7.2-rc1 is out... 

Re: [PATCH dovetail v9 00/11] riscv: Add dovetail support

[Philippe Gerum]

Florian Bezdeka <florian.bezdeka@siemens.com> writes:

> On Fri, 2026-07-03 at 17:27 +0200, Tobias Schaffner wrote:
>> Hi all,
>> 
>> this series introduces initial support for Dovetail on RISC-V.
>> 
>> Feedback, suggestions, and especially reviews are very welcome.
>> 
>> Changes since v1:
>>  * Disable independent irq/softirq stack usage when pipelining
>>  * Drop KVM changes as long as they can not be properly tested
>> 
>> Changes since v2:
>>  * Rework trap handling
>> 
>> Changes since v3:
>>  * Included the IRQ pipelining patches to have all riscv specific
>>    patches included
>>  * Rebased to dovetail/v6.18.y-dovetail-rebase
>>  * Merged most of the fixes
>>  * Fixed IRQ Stack handling and enabled IRQ_STACKS again
>> 
>> Changes since v4:
>>  * Rebased to dovetail/v7.0.y-dovetail-rebase
>>  * Applied suggestions from the last patch set
>>  * Added starfive-visionfive2 board support
>>  * Introduced raw console device based on sbi debug console
>>  * Reworked pipelined irq handling
>> 
>> Changes since v5:
>>  * Rebased to tip of dovetail/v7.0.y-dovetail-rebase
>>  * Applied suggestions from the last patch set
>>  * Use mark_trap_entry/exit_raw for kernel mode exception paths which
>>    use irq_nmi_entry/exit for now, as the nmi irq handlers expect hard
>>    irqs to stay off. This may be be subject to further optimization at
>>    a later stage, but I do not see any negative impact latency wise in
>>    my tests.
>> 
>> Changes since v6:
>> Address the review comments from the last patch set:
>>  * Keep the virtual irq state in sync with the hard irq state in trap
>>    handlers
>>  * Fix irq_nesting imbalance when running with disabled IRQ_STACKS
>> 
>> Changes since v7:
>>  * Simplify Trap handling
>>  * Rebase to wip/flo/v7.1-dovetail-rebase
>> 
>> Changes since v8:
>>  * Further simplify trap handling adressing Florians suggestions and
>>    recent fixes to irq-entry-common
>
> Minor:
>
>  - Changelog in reverse order, newest first
>  - Enumeration of changed patches, so we don't have to review all
>    of them again.
>
>
>
> Philippe, how do we proceed here? Do you want me to update the +riscv
> branches that we have for 7.1 and than take over from there? Or should
> we move it to the 7.2 cycle?
>
> Same question for 7.1: How do we proceed as 7.2-rc1 is out... 

Please pick the risc-v port for 7.1, then I'll handle the forward port
to 7.2 from there.

-- 
Philippe.

Re: [PATCH dovetail v9 11/11] riscv: dovetail: add core support

[Florian Bezdeka]

On Fri, 2026-07-03 at 17:27 +0200, Tobias Schaffner wrote:
> @@ -359,6 +391,15 @@ void do_trap_ecall_u(struct pt_regs *regs)
>  
>  		syscall = syscall_enter_from_user_mode(regs, syscall);
>  
> +		if(dovetailing()) {

checkpatch:

ERROR: space required before the open parenthesis '('
#1426: FILE: arch/riscv/kernel/traps.c:394:
+		if(dovetailing()) {


Please double check checkpatch output for the complete series, there
seems room for improvement.

> +			if (syscall == EXIT_SYSCALL_OOB) {
> +				hard_local_irq_disable();
> +				return;
> +			}
> +			if (syscall == EXIT_SYSCALL_TAIL)
> +				goto done_inband;
> +		}
> +

Re: [PATCH dovetail v9 11/11] riscv: dovetail: add core support

[Tobias Schaffner]

On 7/6/26 17:06, Florian Bezdeka wrote:
> On Fri, 2026-07-03 at 17:27 +0200, Tobias Schaffner wrote:
>> @@ -359,6 +391,15 @@ void do_trap_ecall_u(struct pt_regs *regs)
>>   
>>   		syscall = syscall_enter_from_user_mode(regs, syscall);
>>   
>> +		if(dovetailing()) {
> 
> checkpatch:
> 
> ERROR: space required before the open parenthesis '('
> #1426: FILE: arch/riscv/kernel/traps.c:394:
> +		if(dovetailing()) {
> 
> 
> Please double check checkpatch output for the complete series, there
> seems room for improvement.

Ah... That's the only checkpatch comlain. I will send a new version.

>> +			if (syscall == EXIT_SYSCALL_OOB) {
>> +				hard_local_irq_disable();
>> +				return;
>> +			}
>> +			if (syscall == EXIT_SYSCALL_TAIL)
>> +				goto done_inband;
>> +		}
>> +

Re: [PATCH dovetail v9 11/11] riscv: dovetail: add core support

[Florian Bezdeka]

On Mon, 2026-07-06 at 19:16 +0200, Tobias Schaffner wrote:
> On 7/6/26 17:06, Florian Bezdeka wrote:
> > On Fri, 2026-07-03 at 17:27 +0200, Tobias Schaffner wrote:
> > > @@ -359,6 +391,15 @@ void do_trap_ecall_u(struct pt_regs *regs)
> > >   
> > >   		syscall = syscall_enter_from_user_mode(regs, syscall);
> > >   
> > > +		if(dovetailing()) {
> > 
> > checkpatch:
> > 
> > ERROR: space required before the open parenthesis '('
> > #1426: FILE: arch/riscv/kernel/traps.c:394:
> > +		if(dovetailing()) {
> > 
> > 
> > Please double check checkpatch output for the complete series, there
> > seems room for improvement.
> 
> Ah... That's the only checkpatch comlain. I will send a new version.

Looking at the complete series there is more...

The most important ones (on v10):

WARNING: function definition argument 'struct pt_regs *' should also
have an identifier name
#271: FILE: arch/riscv/include/asm/irq_pipeline.h:131:
+extern void (*handle_arch_irq)(struct pt_regs *);

WARNING: Missing a blank line after declarations
#682: FILE: arch/riscv/kernel/traps.c:455:
+	struct pt_regs *old_regs = set_irq_regs(regs);
+	handle_arch_irq(regs);

WARNING: Missing or malformed SPDX-License-Identifier tag in line 1
#1174: FILE: arch/riscv/include/asm/dovetail.h:1:
+/*

WARNING: Misplaced SPDX-License-Identifier tag - use line 1 instead
#1175: FILE: arch/riscv/include/asm/dovetail.h:2:
+* SPDX-License-Identifier: GPL-2.0

WARNING: Block comments should align the * on each line
#1175: FILE: arch/riscv/include/asm/dovetail.h:2:
+/*
+* SPDX-License-Identifier: GPL-2.0

Any reasons why you didn't address all those further warnings?

Btw: Line numbers above relate to a one-series mailbox file compiled by
b4: 

b4 am <your-message-id-from-the-list>
scripts/checkpatch <generated.mbox>

> 
> > > +			if (syscall == EXIT_SYSCALL_OOB) {
> > > +				hard_local_irq_disable();
> > > +				return;
> > > +			}
> > > +			if (syscall == EXIT_SYSCALL_TAIL)
> > > +				goto done_inband;
> > > +		}
> > > +

Re: [PATCH dovetail v9 11/11] riscv: dovetail: add core support

[Tobias Schaffner]

On 7/8/26 00:18, Florian Bezdeka wrote:
> On Mon, 2026-07-06 at 19:16 +0200, Tobias Schaffner wrote:
>> On 7/6/26 17:06, Florian Bezdeka wrote:
>>> On Fri, 2026-07-03 at 17:27 +0200, Tobias Schaffner wrote:
>>>> @@ -359,6 +391,15 @@ void do_trap_ecall_u(struct pt_regs *regs)
>>>>    
>>>>    		syscall = syscall_enter_from_user_mode(regs, syscall);
>>>>    
>>>> +		if(dovetailing()) {
>>>
>>> checkpatch:
>>>
>>> ERROR: space required before the open parenthesis '('
>>> #1426: FILE: arch/riscv/kernel/traps.c:394:
>>> +		if(dovetailing()) {
>>>
>>>
>>> Please double check checkpatch output for the complete series, there
>>> seems room for improvement.
>>
>> Ah... That's the only checkpatch comlain. I will send a new version.
> 
> Looking at the complete series there is more...
> 
> The most important ones (on v10):
> 
> WARNING: function definition argument 'struct pt_regs *' should also
> have an identifier name
> #271: FILE: arch/riscv/include/asm/irq_pipeline.h:131:
> +extern void (*handle_arch_irq)(struct pt_regs *);
> 
> WARNING: Missing a blank line after declarations
> #682: FILE: arch/riscv/kernel/traps.c:455:
> +	struct pt_regs *old_regs = set_irq_regs(regs);
> +	handle_arch_irq(regs);
> 
> WARNING: Missing or malformed SPDX-License-Identifier tag in line 1
> #1174: FILE: arch/riscv/include/asm/dovetail.h:1:
> +/*
> 
> WARNING: Misplaced SPDX-License-Identifier tag - use line 1 instead
> #1175: FILE: arch/riscv/include/asm/dovetail.h:2:
> +* SPDX-License-Identifier: GPL-2.0
> 
> WARNING: Block comments should align the * on each line
> #1175: FILE: arch/riscv/include/asm/dovetail.h:2:
> +/*
> +* SPDX-License-Identifier: GPL-2.0
> 
> Any reasons why you didn't address all those further warnings?

Got it. My tooling filtered these warning as long as there is no
error. I fixed the last styling issues and will push them in a few
minutes.

> Btw: Line numbers above relate to a one-series mailbox file compiled by
> b4:
> 
> b4 am <your-message-id-from-the-list>
> scripts/checkpatch <generated.mbox>
> 
>>
>>>> +			if (syscall == EXIT_SYSCALL_OOB) {
>>>> +				hard_local_irq_disable();
>>>> +				return;
>>>> +			}
>>>> +			if (syscall == EXIT_SYSCALL_TAIL)
>>>> +				goto done_inband;
>>>> +		}
>>>> +