[PATCH 1/6] powerpc: Add ppc_md.name to dump stack arch description

[PATCH 1/6] powerpc: Add ppc_md.name to dump stack arch description

[Michael Ellerman]

As soon as we know the name of the machine description we're using,
add it to the dump stack arch description, which is printed in case of
an oops.

eg: Hardware name: ... machine:pSeries

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/include/asm/setup.h   |  2 ++
 arch/powerpc/kernel/setup-common.c | 14 ++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h
index 85143849a586..e29e83f8a89c 100644
--- a/arch/powerpc/include/asm/setup.h
+++ b/arch/powerpc/include/asm/setup.h
@@ -88,6 +88,8 @@ unsigned long __init prom_init(unsigned long r3, unsigned long r4,
 			       unsigned long pp, unsigned long r6,
 			       unsigned long r7, unsigned long kbase);
 
+extern struct seq_buf ppc_hw_desc;
+
 #endif /* !__ASSEMBLY__ */
 
 #endif	/* _ASM_POWERPC_SETUP_H */
diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
index dd98f43bd685..42279c3f1d31 100644
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -18,6 +18,7 @@
 #include <linux/delay.h>
 #include <linux/initrd.h>
 #include <linux/platform_device.h>
+#include <linux/printk.h>
 #include <linux/seq_file.h>
 #include <linux/ioport.h>
 #include <linux/console.h>
@@ -25,6 +26,7 @@
 #include <linux/root_dev.h>
 #include <linux/cpu.h>
 #include <linux/unistd.h>
+#include <linux/seq_buf.h>
 #include <linux/serial.h>
 #include <linux/serial_8250.h>
 #include <linux/percpu.h>
@@ -588,6 +590,15 @@ static __init int add_pcspkr(void)
 device_initcall(add_pcspkr);
 #endif	/* CONFIG_PCSPKR_PLATFORM */
 
+static char ppc_hw_desc_buf[128] __initdata;
+
+struct seq_buf ppc_hw_desc __initdata = {
+	.buffer = ppc_hw_desc_buf,
+	.size = sizeof(ppc_hw_desc_buf),
+	.len = 0,
+	.readpos = 0,
+};
+
 static __init void probe_machine(void)
 {
 	extern struct machdep_calls __machine_desc_start;
@@ -628,6 +639,9 @@ static __init void probe_machine(void)
 		for (;;);
 	}
 
+	seq_buf_printf(&ppc_hw_desc,"machine:%s ", ppc_md.name);
+	dump_stack_set_arch_desc(ppc_hw_desc.buffer);
+
 	printk(KERN_INFO "Using %s machine description\n", ppc_md.name);
 }
 
-- 
2.37.3

[PATCH 2/6] powerpc: Add PVR & CPU name to dump stack arch description

[Michael Ellerman]

Add the PVR and CPU name to the dump stack arch description, which is
printed in case of an oops.

eg: Hardware name: ... POWER8E (raw) pvr:0x4b0201

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/kernel/prom.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 2e7a04dab2f7..7987d69f1785 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -30,6 +30,7 @@
 #include <linux/libfdt.h>
 #include <linux/cpu.h>
 #include <linux/pgtable.h>
+#include <linux/seq_buf.h>
 
 #include <asm/rtas.h>
 #include <asm/page.h>
@@ -819,6 +820,10 @@ void __init early_init_devtree(void *params)
 
 	dt_cpu_ftrs_scan();
 
+	/* We can now set the CPU name & PVR for the oops output */
+	seq_buf_printf(&ppc_hw_desc, "%s pvr:0x%04lx ", cur_cpu_spec->cpu_name,
+		       mfspr(SPRN_PVR));
+
 	/* Retrieve CPU related informations from the flat tree
 	 * (altivec support, boot CPU ID, ...)
 	 */
-- 
2.37.3

[PATCH 3/6] powerpc/64: Add logical PVR to the dump stack arch description

[Michael Ellerman]

If we detect a logical PVR add that to the dump stack arch
description, which is printed in case of an oops.

eg: Hardware name: ... lpvr:0xf000004

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/kernel/prom.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 7987d69f1785..dca06ef7fcde 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -390,8 +390,10 @@ static int __init early_init_dt_scan_cpus(unsigned long node,
 	 */
 	if (!dt_cpu_ftrs_in_use()) {
 		prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
-		if (prop && (be32_to_cpup(prop) & 0xff000000) == 0x0f000000)
+		if (prop && (be32_to_cpup(prop) & 0xff000000) == 0x0f000000) {
 			identify_cpu(0, be32_to_cpup(prop));
+			seq_buf_printf(&ppc_hw_desc, "lpvr:0x%04x ", be32_to_cpup(prop));
+		}
 
 		check_cpu_feature_properties(node);
 		check_cpu_features(node, "ibm,pa-features", ibm_pa_features,
-- 
2.37.3

[PATCH 4/6] powerpc: Add device-tree model to dump stack arch description

[Michael Ellerman]

Add the model of the machine we're on to the dump stack arch
description, which is printed in case of an oops.

eg: Hardware name: model:'IBM,8247-22L'

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/kernel/prom.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index dca06ef7fcde..605e4ad8a4c2 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -715,6 +715,23 @@ static void __init tm_init(void)
 static void tm_init(void) { }
 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
 
+static int __init
+early_init_dt_scan_model(unsigned long node, const char *uname,
+			 int depth, void *data)
+{
+	const char *prop;
+
+	if (depth != 0)
+		return 0;
+
+	prop = of_get_flat_dt_prop(node, "model", NULL);
+	if (prop)
+		seq_buf_printf(&ppc_hw_desc, "model:'%s' ", prop);
+
+	/* break now */
+	return 1;
+}
+
 #ifdef CONFIG_PPC64
 static void __init save_fscr_to_task(void)
 {
@@ -743,6 +760,8 @@ void __init early_init_devtree(void *params)
 	if (!early_init_dt_verify(params))
 		panic("BUG: Failed verifying flat device tree, bad version?");
 
+	of_scan_flat_dt(early_init_dt_scan_model, NULL);
+
 #ifdef CONFIG_PPC_RTAS
 	/* Some machines might need RTAS info for debugging, grab it now. */
 	of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
-- 
2.37.3

[PATCH 5/6] powerpc/powernv: Add opal details to dump stack arch description

[Michael Ellerman]

Add OPAL version details to the dump stack arch description, which is
printed in case of an oops.

eg: Hardware name: ... opal:v6.2

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/powernv/setup.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index dac545aa0308..fddc61ec1d5b 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -17,6 +17,7 @@
 #include <linux/console.h>
 #include <linux/delay.h>
 #include <linux/irq.h>
+#include <linux/seq_buf.h>
 #include <linux/seq_file.h>
 #include <linux/of.h>
 #include <linux/of_fdt.h>
@@ -207,8 +208,33 @@ static void __init pnv_setup_arch(void)
 	pnv_rng_init();
 }
 
+static void __init pnv_add_dump_stack_arch_desc(void)
+{
+	struct device_node *dn;
+	const char *version;
+
+	dn = of_find_node_by_path("/ibm,opal/firmware");
+	if (!dn)
+		return;
+
+	version = of_get_property(dn, "version", NULL);
+	if (!version)
+		version = of_get_property(dn, "git-id", NULL);
+
+	if (version)
+		seq_buf_printf(&ppc_hw_desc, "opal:%s", version);
+
+	version = of_get_property(dn, "mi-version", NULL);
+	if (version)
+		seq_buf_printf(&ppc_hw_desc, "mi:%s", version);
+
+	of_node_put(dn);
+}
+
 static void __init pnv_init(void)
 {
+	pnv_add_dump_stack_arch_desc();
+
 	/*
 	 * Initialize the LPC bus now so that legacy serial
 	 * ports can be found on it
-- 
2.37.3

[PATCH 6/6] powerpc/pseries: Add firmware details to dump stack arch description

[Michael Ellerman]

Add firmware version details to the dump stack arch description, which
is printed in case of an oops.

Currently /hypervisor only exists on KVM, so if we don't find that
look for something that suggests we're on phyp and if so that's
probably a good guess. The actual content of the ibm,fw-net-version
seems to be a full path so is too long to add to the description.

eg: Hardware name: ... of:'IBM,FW860.42 (SV860_138)' hv:phyp

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/pseries/setup.c | 36 ++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 5e44c65a032c..f0ce8256ebb8 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -41,6 +41,7 @@
 #include <linux/of_pci.h>
 #include <linux/memblock.h>
 #include <linux/swiotlb.h>
+#include <linux/seq_buf.h>
 
 #include <asm/mmu.h>
 #include <asm/processor.h>
@@ -1011,6 +1012,39 @@ static void __init pSeries_cmo_feature_init(void)
 	pr_debug(" <- fw_cmo_feature_init()\n");
 }
 
+static void __init pseries_add_dump_stack_arch_desc(void)
+{
+	struct device_node *dn;
+	const char *prop;
+
+	dn = of_find_node_by_path("/openprom");
+	if (dn) {
+		prop = of_get_property(dn, "model", NULL);
+		if (prop)
+			seq_buf_printf(&ppc_hw_desc, "of:'%s' ", prop);
+
+		of_node_put(dn);
+	}
+
+	dn = of_find_node_by_path("/hypervisor");
+	if (dn) {
+		prop = of_get_property(dn, "compatible", NULL);
+		if (prop)
+			seq_buf_printf(&ppc_hw_desc, "hv:%s ", prop);
+
+		of_node_put(dn);
+	} else {
+		dn = of_find_node_by_path("/");
+		if (dn) {
+			prop = of_get_property(dn, "ibm,fw-net-version", NULL);
+			if (prop)
+				seq_buf_printf(&ppc_hw_desc, "hv:phyp ");
+
+			of_node_put(dn);
+		}
+	}
+}
+
 /*
  * Early initialization.  Relocation is on but do not reference unbolted pages
  */
@@ -1018,6 +1052,8 @@ static void __init pseries_init(void)
 {
 	pr_debug(" -> pseries_init()\n");
 
+	pseries_add_dump_stack_arch_desc();
+
 #ifdef CONFIG_HVC_CONSOLE
 	if (firmware_has_feature(FW_FEATURE_LPAR))
 		hvc_vio_init_early();
-- 
2.37.3

Re: [PATCH 6/6] powerpc/pseries: Add firmware details to dump stack arch description

[Nathan Lynch]

Michael Ellerman <mpe@ellerman.id.au> writes:

> Add firmware version details to the dump stack arch description, which
> is printed in case of an oops.
>
> Currently /hypervisor only exists on KVM, so if we don't find that
> look for something that suggests we're on phyp and if so that's
> probably a good guess. The actual content of the ibm,fw-net-version
> seems to be a full path so is too long to add to the description.

My only reservation is that ibm,fw-net-version seems to be unspecified
and could disappear in future firmware versions.

/ibm,powervm-partition would be the best PAPR-specified property for
this purpose, but I don't see it on a P8/860 partition I checked,
unfortunately. I do see it on a P9. Presumably it's present in device
trees on PowerVM P9 systems and later, but it's probably too new to use
for this.

/ibm,lpar-capable "indicates that the platform is capable of supporting
logical partitioning and is only present on such systems." This one is
present on the P8.

So consider this a weak suggestion to replace the ibm,fw-net-version
check with ibm,lpar-capable. But I don't want to bikeshed it, overall
the series looks good.

>
> eg: Hardware name: ... of:'IBM,FW860.42 (SV860_138)' hv:phyp

Will this info get printed during boot as well? There are many times it
would have been useful to me when looking at logs from non-oopsed
kernels.

Re: [PATCH 1/6] powerpc: Add ppc_md.name to dump stack arch description

[Nathan Lynch]

Michael Ellerman <mpe@ellerman.id.au> writes:
> @@ -588,6 +590,15 @@ static __init int add_pcspkr(void)
>  device_initcall(add_pcspkr);
>  #endif	/* CONFIG_PCSPKR_PLATFORM */
>  
> +static char ppc_hw_desc_buf[128] __initdata;
> +
> +struct seq_buf ppc_hw_desc __initdata = {
> +	.buffer = ppc_hw_desc_buf,
> +	.size = sizeof(ppc_hw_desc_buf),
> +	.len = 0,
> +	.readpos = 0,
> +};
> +
>  static __init void probe_machine(void)
>  {
>  	extern struct machdep_calls __machine_desc_start;
> @@ -628,6 +639,9 @@ static __init void probe_machine(void)
>  		for (;;);
>  	}
>  
> +	seq_buf_printf(&ppc_hw_desc,"machine:%s ", ppc_md.name);
> +	dump_stack_set_arch_desc(ppc_hw_desc.buffer);

At first I was confused by the seemingly unnecessary use of the seq_buf,
but after reading the rest of the series I see that this is the final
addition to a temporary buffer before setting the arch description
string. Looks OK to me.

Re: [PATCH 6/6] powerpc/pseries: Add firmware details to dump stack arch description

[Michael Ellerman]

Nathan Lynch <nathanl@linux.ibm.com> writes:
> Michael Ellerman <mpe@ellerman.id.au> writes:
>
>> Add firmware version details to the dump stack arch description, which
>> is printed in case of an oops.
>>
>> Currently /hypervisor only exists on KVM, so if we don't find that
>> look for something that suggests we're on phyp and if so that's
>> probably a good guess. The actual content of the ibm,fw-net-version
>> seems to be a full path so is too long to add to the description.
>
> My only reservation is that ibm,fw-net-version seems to be unspecified
> and could disappear in future firmware versions.

Yeah good point.

> /ibm,powervm-partition would be the best PAPR-specified property for
> this purpose, but I don't see it on a P8/860 partition I checked,
> unfortunately. I do see it on a P9. Presumably it's present in device
> trees on PowerVM P9 systems and later, but it's probably too new to use
> for this.

I'll look for both, it's easy enough.

> /ibm,lpar-capable "indicates that the platform is capable of supporting
> logical partitioning and is only present on such systems." This one is
> present on the P8.

But conceivably qemu/KVM could provide that property, which would defeat
the purpose here which is to differentiate which actual hypervisor we're
under.

>> eg: Hardware name: ... of:'IBM,FW860.42 (SV860_138)' hv:phyp
>
> Will this info get printed during boot as well? There are many times it
> would have been useful to me when looking at logs from non-oopsed
> kernels.

No it's not. But you're right that would often be useful.

I think we can print it at the end of probe_machine().

I'll send a v2.

cheers

[PATCH 5/6] powerpc/powernv: Add opal details to dump stack arch description

[Michael Ellerman]

Once we have unflattened the device tree we can easily grab these opal
version details and add them to dump stack arch description, which is
printed in case of an oops.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/powernv/setup.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 16fdcb23f4c3..9250552d4b42 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -62,8 +62,34 @@ static void __init pnv_setup_arch(void)
 	/* XXX PMCS */
 }
 
+static void __init pnv_add_dump_stack_arch_desc(void)
+{
+	struct device_node *dn;
+	const char *version;
+
+	dn = of_find_node_by_path("/ibm,opal/firmware");
+	if (!dn)
+		return;
+
+	version = of_get_property(dn, "version", NULL);
+	if (version)
+		dump_stack_add_arch_desc(version);
+
+	version = of_get_property(dn, "git-id", NULL);
+	if (version)
+		dump_stack_add_arch_desc(version);
+
+	version = of_get_property(dn, "mi-version", NULL);
+	if (version)
+		dump_stack_add_arch_desc(version);
+
+	of_node_put(dn);
+}
+
 static void __init pnv_init_early(void)
 {
+	pnv_add_dump_stack_arch_desc();
+
 	/*
 	 * Initialize the LPC bus now so that legacy serial
 	 * ports can be found on it
-- 
2.1.0