RISC-V Fixes for 5.17-rc6

* A fix for the K210 sdcard defconfig, to avoid using a fixed delay for
   the root FS.
 * A fix to make sure there's a proper call frame for
   trace_hardirqs_{on,off}().
 
 ---
 
 There are a handful of additional fixes in flight, but not for this
 week.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCAAxFiEEAM520YNJYN/OiG3470yhUCzLq0EFAmIZHmQTHHBhbG1lckBk
 YWJiZWx0LmNvbQAKCRDvTKFQLMurQT4ND/42sEQLhcQcDpdvFDX/0zBr1Y8RNy25
 7I9JBYmuTK5AfwmE52I/OcdCLE9bNELH1g+LMK/3amEqhkUtDelBb5UdC4TYfvRm
 SRlj75XKPxESMEW9EjU5BeAz+uDI4oMkOmDPyp+Xv/OayGrFQIPUTo75/SiOdlH7
 a2khiH4/OxqkVlOff3Ko96M4RNSUeUIEVSfrH4pgJC8n+031u02TvR1IIx5TT7ti
 W5YIMw6VZ32Gl5ByZaBMbs9pz+iOKDrn3UfnPrVpbs6P3389EmR4btJpqfzN9JeC
 UQzcx4rqoDzTtJvqkOxiR+Ig4nNJGyeYVvxaGH67MkD/nz6rS26adIs+xPGKjDCC
 TtFyLt4h2+JX+1kNiutTLrQLAaQO4N+LSkysIsoSr9wNGCdnSrAQRxoOLwIuTMBS
 61kRsBvuiuRJZQlbgkP2tiTug/8dYs4vQzPNeC5VO/c3MZB5/j2ykYdKBSsElrpi
 +br602CMdeqvT+M+pT9lWdxa8X9lbYVm1z3hx2FyRdbnYw3nbcQq/mGp8Ju9O5zt
 JXajwPFtUPpWXzm2CcRjeh+2GKoLetgVpwHAIOmnDd6meTXp/BEu12+o7c8vf3H7
 k12BPHVPH1gPklG2Oh8Z/UvevICd4AHlSJT7J19xh7fYVMaaALVQ71Nd2jFbv9N/
 eu8KKxR2pKXiPw==
 =1a16
 -----END PGP SIGNATURE-----

Merge tag 'riscv-for-linus-5.17-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V fixes from Palmer Dabbelt:

 - A fix for the K210 sdcard defconfig, to avoid using a
   fixed delay for the root FS

 - A fix to make sure there's a proper call frame for
   trace_hardirqs_{on,off}().

* tag 'riscv-for-linus-5.17-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: fix oops caused by irqsoff latency tracer
  riscv: fix nommu_k210_sdcard_defconfig

arch/riscv/configs/nommu_k210_sdcard_defconfig

@@ -23,7 +23,7 @@ CONFIG_SLOB=y
 CONFIG_SOC_CANAAN=y
 CONFIG_SMP=y
 CONFIG_NR_CPUS=2
-CONFIG_CMDLINE="earlycon console=ttySIF0 rootdelay=2 root=/dev/mmcblk0p1 ro"
+CONFIG_CMDLINE="earlycon console=ttySIF0 root=/dev/mmcblk0p1 rootwait ro"
 CONFIG_CMDLINE_FORCE=y
 # CONFIG_SECCOMP is not set
 # CONFIG_STACKPROTECTOR is not set

arch/riscv/kernel/Makefile

@@ -51,6 +51,8 @@ obj-$(CONFIG_MODULE_SECTIONS)	+= module-sections.o
 obj-$(CONFIG_FUNCTION_TRACER)	+= mcount.o ftrace.o
 obj-$(CONFIG_DYNAMIC_FTRACE)	+= mcount-dyn.o
 
+obj-$(CONFIG_TRACE_IRQFLAGS)	+= trace_irq.o
+
 obj-$(CONFIG_RISCV_BASE_PMU)	+= perf_event.o
 obj-$(CONFIG_PERF_EVENTS)	+= perf_callchain.o
 obj-$(CONFIG_HAVE_PERF_REGS)	+= perf_regs.o

arch/riscv/kernel/entry.S

@@ -108,7 +108,7 @@ _save_context:
 .option pop
 
 #ifdef CONFIG_TRACE_IRQFLAGS
-	call trace_hardirqs_off
+	call __trace_hardirqs_off
 #endif
 
 #ifdef CONFIG_CONTEXT_TRACKING
@@ -143,7 +143,7 @@ skip_context_tracking:
 	li t0, EXC_BREAKPOINT
 	beq s4, t0, 1f
 #ifdef CONFIG_TRACE_IRQFLAGS
-	call trace_hardirqs_on
+	call __trace_hardirqs_on
 #endif
 	csrs CSR_STATUS, SR_IE
 
@@ -234,7 +234,7 @@ ret_from_exception:
 	REG_L s0, PT_STATUS(sp)
 	csrc CSR_STATUS, SR_IE
 #ifdef CONFIG_TRACE_IRQFLAGS
-	call trace_hardirqs_off
+	call __trace_hardirqs_off
 #endif
 #ifdef CONFIG_RISCV_M_MODE
 	/* the MPP value is too large to be used as an immediate arg for addi */
@@ -270,10 +270,10 @@ restore_all:
 	REG_L s1, PT_STATUS(sp)
 	andi t0, s1, SR_PIE
 	beqz t0, 1f
-	call trace_hardirqs_on
+	call __trace_hardirqs_on
 	j 2f
 1:
-	call trace_hardirqs_off
+	call __trace_hardirqs_off
 2:
 #endif
 	REG_L a0, PT_STATUS(sp)

arch/riscv/kernel/trace_irq.c

@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022 Changbin Du <changbin.du@gmail.com>
+ */
+
+#include <linux/irqflags.h>
+#include <linux/kprobes.h>
+#include "trace_irq.h"
+
+/*
+ * trace_hardirqs_on/off require the caller to setup frame pointer properly.
+ * Otherwise, CALLER_ADDR1 might trigger an pagging exception in kernel.
+ * Here we add one extra level so they can be safely called by low
+ * level entry code which $fp is used for other purpose.
+ */
+
+void __trace_hardirqs_on(void)
+{
+	trace_hardirqs_on();
+}
+NOKPROBE_SYMBOL(__trace_hardirqs_on);
+
+void __trace_hardirqs_off(void)
+{
+	trace_hardirqs_off();
+}
+NOKPROBE_SYMBOL(__trace_hardirqs_off);

arch/riscv/kernel/trace_irq.h

@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2022 Changbin Du <changbin.du@gmail.com>
+ */
+#ifndef __TRACE_IRQ_H
+#define __TRACE_IRQ_H
+
+void __trace_hardirqs_on(void);
+void __trace_hardirqs_off(void);
+
+#endif /* __TRACE_IRQ_H */