arch/powerpc/kernel/nvram_64.c | 8 ++++---- arch/powerpc/platforms/powernv/opal-kmsg.c | 4 ++-- arch/um/kernel/kmsg_dump.c | 2 +- drivers/gpu/drm/drm_panic.c | 4 ++-- drivers/hv/hv_common.c | 4 ++-- drivers/mtd/mtdoops.c | 2 +- fs/pstore/platform.c | 10 +++++----- include/linux/kmsg_dump.h | 22 +++++++++++++++++++--- kernel/panic.c | 2 +- kernel/printk/printk.c | 11 ++++++++--- 10 files changed, 45 insertions(+), 24 deletions(-)
kmsg_dump doesn't forward the panic reason string to the kmsg_dumper
callback.
This patch adds a new struct kmsg_dump_detail, that will hold the
reason and description, and pass it to the dump() callback.
To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc()
function and a macro for backward compatibility.
I've written this for drm_panic, but it can be useful for other
kmsg_dumper.
It allows to see the panic reason, like "sysrq triggered crash"
or "VFS: Unable to mount root fs on xxxx" on the drm panic screen.
v2:
* Use a struct kmsg_dump_detail to hold the reason and description
pointer, for more flexibility if we want to add other parameters.
(Kees Cook)
* Fix powerpc/nvram_64 build, as I didn't update the forward
declaration of oops_to_nvram()
Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
---
arch/powerpc/kernel/nvram_64.c | 8 ++++----
arch/powerpc/platforms/powernv/opal-kmsg.c | 4 ++--
arch/um/kernel/kmsg_dump.c | 2 +-
drivers/gpu/drm/drm_panic.c | 4 ++--
drivers/hv/hv_common.c | 4 ++--
drivers/mtd/mtdoops.c | 2 +-
fs/pstore/platform.c | 10 +++++-----
include/linux/kmsg_dump.h | 22 +++++++++++++++++++---
kernel/panic.c | 2 +-
kernel/printk/printk.c | 11 ++++++++---
10 files changed, 45 insertions(+), 24 deletions(-)
diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c
index e385d3164648..f9c6568a9137 100644
--- a/arch/powerpc/kernel/nvram_64.c
+++ b/arch/powerpc/kernel/nvram_64.c
@@ -73,7 +73,7 @@ static const char *nvram_os_partitions[] = {
};
static void oops_to_nvram(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason);
+ struct kmsg_dump_detail *detail);
static struct kmsg_dumper nvram_kmsg_dumper = {
.dump = oops_to_nvram
@@ -643,7 +643,7 @@ void __init nvram_init_oops_partition(int rtas_partition_exists)
* partition. If that's too much, go back and capture uncompressed text.
*/
static void oops_to_nvram(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason)
+ struct kmsg_dump_detail *detail)
{
struct oops_log_info *oops_hdr = (struct oops_log_info *)oops_buf;
static unsigned int oops_count = 0;
@@ -655,7 +655,7 @@ static void oops_to_nvram(struct kmsg_dumper *dumper,
unsigned int err_type = ERR_TYPE_KERNEL_PANIC_GZ;
int rc = -1;
- switch (reason) {
+ switch (detail->reason) {
case KMSG_DUMP_SHUTDOWN:
/* These are almost always orderly shutdowns. */
return;
@@ -671,7 +671,7 @@ static void oops_to_nvram(struct kmsg_dumper *dumper,
break;
default:
pr_err("%s: ignoring unrecognized KMSG_DUMP_* reason %d\n",
- __func__, (int) reason);
+ __func__, (int) detail->reason);
return;
}
diff --git a/arch/powerpc/platforms/powernv/opal-kmsg.c b/arch/powerpc/platforms/powernv/opal-kmsg.c
index 6c3bc4b4da98..bb4218fa796e 100644
--- a/arch/powerpc/platforms/powernv/opal-kmsg.c
+++ b/arch/powerpc/platforms/powernv/opal-kmsg.c
@@ -20,13 +20,13 @@
* message, it just ensures that OPAL completely flushes the console buffer.
*/
static void kmsg_dump_opal_console_flush(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason)
+ struct kmsg_dump_detail *detail)
{
/*
* Outside of a panic context the pollers will continue to run,
* so we don't need to do any special flushing.
*/
- if (reason != KMSG_DUMP_PANIC)
+ if (detail->reason != KMSG_DUMP_PANIC)
return;
opal_flush_console(0);
diff --git a/arch/um/kernel/kmsg_dump.c b/arch/um/kernel/kmsg_dump.c
index 4382cf02a6d1..419021175272 100644
--- a/arch/um/kernel/kmsg_dump.c
+++ b/arch/um/kernel/kmsg_dump.c
@@ -8,7 +8,7 @@
#include <os.h>
static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason)
+ struct kmsg_dump_detail *detail)
{
static struct kmsg_dump_iter iter;
static DEFINE_SPINLOCK(lock);
diff --git a/drivers/gpu/drm/drm_panic.c b/drivers/gpu/drm/drm_panic.c
index 948aed00595e..8794c7f6c0ee 100644
--- a/drivers/gpu/drm/drm_panic.c
+++ b/drivers/gpu/drm/drm_panic.c
@@ -655,11 +655,11 @@ static struct drm_plane *to_drm_plane(struct kmsg_dumper *kd)
return container_of(kd, struct drm_plane, kmsg_panic);
}
-static void drm_panic(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason)
+static void drm_panic(struct kmsg_dumper *dumper, struct kmsg_dump_detail *detail)
{
struct drm_plane *plane = to_drm_plane(dumper);
- if (reason == KMSG_DUMP_PANIC)
+ if (detail->reason == KMSG_DUMP_PANIC)
draw_panic_plane(plane);
}
diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
index 9c452bfbd571..7a35c82976e0 100644
--- a/drivers/hv/hv_common.c
+++ b/drivers/hv/hv_common.c
@@ -207,13 +207,13 @@ static int hv_die_panic_notify_crash(struct notifier_block *self,
* buffer and call into Hyper-V to transfer the data.
*/
static void hv_kmsg_dump(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason)
+ struct kmsg_dump_detail *detail)
{
struct kmsg_dump_iter iter;
size_t bytes_written;
/* We are only interested in panics. */
- if (reason != KMSG_DUMP_PANIC || !sysctl_record_panic_msg)
+ if (detail->reason != KMSG_DUMP_PANIC || !sysctl_record_panic_msg)
return;
/*
diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c
index 2f11585b5613..86d49db9196d 100644
--- a/drivers/mtd/mtdoops.c
+++ b/drivers/mtd/mtdoops.c
@@ -298,7 +298,7 @@ static void find_next_position(struct mtdoops_context *cxt)
}
static void mtdoops_do_dump(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason)
+ struct kmsg_dump_detail *detail)
{
struct mtdoops_context *cxt = container_of(dumper,
struct mtdoops_context, dump);
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 3497ede88aa0..9c6b7c97fa3c 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -275,7 +275,7 @@ void pstore_record_init(struct pstore_record *record,
* end of the buffer.
*/
static void pstore_dump(struct kmsg_dumper *dumper,
- enum kmsg_dump_reason reason)
+ struct kmsg_dump_detail *detail)
{
struct kmsg_dump_iter iter;
unsigned long total = 0;
@@ -285,9 +285,9 @@ static void pstore_dump(struct kmsg_dumper *dumper,
int saved_ret = 0;
int ret;
- why = kmsg_dump_reason_str(reason);
+ why = kmsg_dump_reason_str(detail->reason);
- if (pstore_cannot_block_path(reason)) {
+ if (pstore_cannot_block_path(detail->reason)) {
if (!spin_trylock_irqsave(&psinfo->buf_lock, flags)) {
pr_err("dump skipped in %s path because of concurrent dump\n",
in_nmi() ? "NMI" : why);
@@ -311,7 +311,7 @@ static void pstore_dump(struct kmsg_dumper *dumper,
pstore_record_init(&record, psinfo);
record.type = PSTORE_TYPE_DMESG;
record.count = oopscount;
- record.reason = reason;
+ record.reason = detail->reason;
record.part = part;
record.buf = psinfo->buf;
@@ -352,7 +352,7 @@ static void pstore_dump(struct kmsg_dumper *dumper,
}
ret = psinfo->write(&record);
- if (ret == 0 && reason == KMSG_DUMP_OOPS) {
+ if (ret == 0 && detail->reason == KMSG_DUMP_OOPS) {
pstore_new_entry = 1;
pstore_timer_kick();
} else {
diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h
index 906521c2329c..65f5a47727bc 100644
--- a/include/linux/kmsg_dump.h
+++ b/include/linux/kmsg_dump.h
@@ -39,6 +39,17 @@ struct kmsg_dump_iter {
u64 next_seq;
};
+/**
+ *struct kmsg_dump_detail - kernel crash detail
+ * @reason: reason for the crash, see kmsg_dump_reason.
+ * @description: optional short string, to provide additional information.
+ */
+
+struct kmsg_dump_detail {
+ enum kmsg_dump_reason reason;
+ const char *description;
+};
+
/**
* struct kmsg_dumper - kernel crash message dumper structure
* @list: Entry in the dumper list (private)
@@ -49,13 +60,13 @@ struct kmsg_dump_iter {
*/
struct kmsg_dumper {
struct list_head list;
- void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason);
+ void (*dump)(struct kmsg_dumper *dumper, struct kmsg_dump_detail *detail);
enum kmsg_dump_reason max_reason;
bool registered;
};
#ifdef CONFIG_PRINTK
-void kmsg_dump(enum kmsg_dump_reason reason);
+void kmsg_dump_desc(enum kmsg_dump_reason reason, const char *desc);
bool kmsg_dump_get_line(struct kmsg_dump_iter *iter, bool syslog,
char *line, size_t size, size_t *len);
@@ -71,7 +82,7 @@ int kmsg_dump_unregister(struct kmsg_dumper *dumper);
const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason);
#else
-static inline void kmsg_dump(enum kmsg_dump_reason reason)
+static inline void kmsg_dump_desc(enum kmsg_dump_reason reason, const char *desc)
{
}
@@ -107,4 +118,9 @@ static inline const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason)
}
#endif
+static inline void kmsg_dump(enum kmsg_dump_reason reason)
+{
+ kmsg_dump_desc(reason, NULL);
+}
+
#endif /* _LINUX_KMSG_DUMP_H */
diff --git a/kernel/panic.c b/kernel/panic.c
index 0843a275531a..0a8b29c44f3c 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -378,7 +378,7 @@ void panic(const char *fmt, ...)
panic_print_sys_info(false);
- kmsg_dump(KMSG_DUMP_PANIC);
+ kmsg_dump_desc(KMSG_DUMP_PANIC, buf);
/*
* If you doubt kdump always works fine in any situation,
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 5dcc05e1aa56..19bc414be5f0 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -4272,16 +4272,21 @@ const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason)
EXPORT_SYMBOL_GPL(kmsg_dump_reason_str);
/**
- * kmsg_dump - dump kernel log to kernel message dumpers.
+ * kmsg_dump_desc - dump kernel log to kernel message dumpers.
* @reason: the reason (oops, panic etc) for dumping
+ * @desc: a short string to describe what caused the panic or oops. Can be NULL
+ * if no additional description is available.
*
* Call each of the registered dumper's dump() callback, which can
* retrieve the kmsg records with kmsg_dump_get_line() or
* kmsg_dump_get_buffer().
*/
-void kmsg_dump(enum kmsg_dump_reason reason)
+void kmsg_dump_desc(enum kmsg_dump_reason reason, const char *desc)
{
struct kmsg_dumper *dumper;
+ struct kmsg_dump_detail detail = {
+ .reason = reason,
+ .description = desc};
rcu_read_lock();
list_for_each_entry_rcu(dumper, &dump_list, list) {
@@ -4299,7 +4304,7 @@ void kmsg_dump(enum kmsg_dump_reason reason)
continue;
/* invoke dumper which will iterate over records */
- dumper->dump(dumper, reason);
+ dumper->dump(dumper, &detail);
}
rcu_read_unlock();
}
base-commit: 82e4255305c554b0bb18b7ccf2db86041b4c8b6e
--
2.45.2On 7/2/2024 5:26 AM, Jocelyn Falempe wrote: > kmsg_dump doesn't forward the panic reason string to the kmsg_dumper > callback. > This patch adds a new struct kmsg_dump_detail, that will hold the > reason and description, and pass it to the dump() callback. > > To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc() > function and a macro for backward compatibility. > > I've written this for drm_panic, but it can be useful for other > kmsg_dumper. > It allows to see the panic reason, like "sysrq triggered crash" > or "VFS: Unable to mount root fs on xxxx" on the drm panic screen. > > v2: > * Use a struct kmsg_dump_detail to hold the reason and description > pointer, for more flexibility if we want to add other parameters. > (Kees Cook) > * Fix powerpc/nvram_64 build, as I didn't update the forward > declaration of oops_to_nvram() > > Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com> > --- > arch/powerpc/kernel/nvram_64.c | 8 ++++---- > arch/powerpc/platforms/powernv/opal-kmsg.c | 4 ++-- > arch/um/kernel/kmsg_dump.c | 2 +- > drivers/gpu/drm/drm_panic.c | 4 ++-- > drivers/hv/hv_common.c | 4 ++-- Acked-by: Nuno Das Neves <nunodasneves@linux.microsoft.com> (hyperv) LGTM
On 02/07/2024 14:26, Jocelyn Falempe wrote: > kmsg_dump doesn't forward the panic reason string to the kmsg_dumper > callback. > This patch adds a new struct kmsg_dump_detail, that will hold the > reason and description, and pass it to the dump() callback. > > To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc() > function and a macro for backward compatibility. > > I've written this for drm_panic, but it can be useful for other > kmsg_dumper. > It allows to see the panic reason, like "sysrq triggered crash" > or "VFS: Unable to mount root fs on xxxx" on the drm panic screen. > > v2: > * Use a struct kmsg_dump_detail to hold the reason and description > pointer, for more flexibility if we want to add other parameters. > (Kees Cook) > * Fix powerpc/nvram_64 build, as I didn't update the forward > declaration of oops_to_nvram() > > Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com> > --- > arch/powerpc/kernel/nvram_64.c | 8 ++++---- > arch/powerpc/platforms/powernv/opal-kmsg.c | 4 ++-- > arch/um/kernel/kmsg_dump.c | 2 +- > drivers/gpu/drm/drm_panic.c | 4 ++-- > drivers/hv/hv_common.c | 4 ++-- > drivers/mtd/mtdoops.c | 2 +- > fs/pstore/platform.c | 10 +++++----- > include/linux/kmsg_dump.h | 22 +++++++++++++++++++--- > kernel/panic.c | 2 +- > kernel/printk/printk.c | 11 ++++++++--- > 10 files changed, 45 insertions(+), 24 deletions(-) > [...] I pushed it to drm-misc-next, with the whitespace change in kmsg_dump.h Thanks all for your reviews and comments. Best regards, -- Jocelyn
Jocelyn Falempe <jfalempe@redhat.com> writes: > kmsg_dump doesn't forward the panic reason string to the kmsg_dumper > callback. > This patch adds a new struct kmsg_dump_detail, that will hold the > reason and description, and pass it to the dump() callback. > > To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc() > function and a macro for backward compatibility. > > I've written this for drm_panic, but it can be useful for other > kmsg_dumper. > It allows to see the panic reason, like "sysrq triggered crash" > or "VFS: Unable to mount root fs on xxxx" on the drm panic screen. > > v2: > * Use a struct kmsg_dump_detail to hold the reason and description > pointer, for more flexibility if we want to add other parameters. > (Kees Cook) > * Fix powerpc/nvram_64 build, as I didn't update the forward > declaration of oops_to_nvram() > > Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com> > --- > arch/powerpc/kernel/nvram_64.c | 8 ++++---- > arch/powerpc/platforms/powernv/opal-kmsg.c | 4 ++-- Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) cheers
On 02/07/2024 14:26, Jocelyn Falempe wrote:
> kmsg_dump doesn't forward the panic reason string to the kmsg_dumper
> callback.
> This patch adds a new struct kmsg_dump_detail, that will hold the
> reason and description, and pass it to the dump() callback.
>
> To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc()
> function and a macro for backward compatibility.
>
> I've written this for drm_panic, but it can be useful for other
> kmsg_dumper.
> It allows to see the panic reason, like "sysrq triggered crash"
> or "VFS: Unable to mount root fs on xxxx" on the drm panic screen.
>
> v2:
> * Use a struct kmsg_dump_detail to hold the reason and description
> pointer, for more flexibility if we want to add other parameters.
> (Kees Cook)
> * Fix powerpc/nvram_64 build, as I didn't update the forward
> declaration of oops_to_nvram()
>
> Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
> ---
> arch/powerpc/kernel/nvram_64.c | 8 ++++----
> arch/powerpc/platforms/powernv/opal-kmsg.c | 4 ++--
> arch/um/kernel/kmsg_dump.c | 2 +-
> drivers/gpu/drm/drm_panic.c | 4 ++--
> drivers/hv/hv_common.c | 4 ++--
> drivers/mtd/mtdoops.c | 2 +-
> fs/pstore/platform.c | 10 +++++-----
> include/linux/kmsg_dump.h | 22 +++++++++++++++++++---
> kernel/panic.c | 2 +-
> kernel/printk/printk.c | 11 ++++++++---
> 10 files changed, 45 insertions(+), 24 deletions(-)
>
> diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c
> index e385d3164648..f9c6568a9137 100644
> --- a/arch/powerpc/kernel/nvram_64.c
> +++ b/arch/powerpc/kernel/nvram_64.c
> @@ -73,7 +73,7 @@ static const char *nvram_os_partitions[] = {
> };
>
> static void oops_to_nvram(struct kmsg_dumper *dumper,
> - enum kmsg_dump_reason reason);
> + struct kmsg_dump_detail *detail);
>
> static struct kmsg_dumper nvram_kmsg_dumper = {
> .dump = oops_to_nvram
> @@ -643,7 +643,7 @@ void __init nvram_init_oops_partition(int rtas_partition_exists)
> * partition. If that's too much, go back and capture uncompressed text.
> */
> static void oops_to_nvram(struct kmsg_dumper *dumper,
> - enum kmsg_dump_reason reason)
> + struct kmsg_dump_detail *detail)
> {
> struct oops_log_info *oops_hdr = (struct oops_log_info *)oops_buf;
> static unsigned int oops_count = 0;
> @@ -655,7 +655,7 @@ static void oops_to_nvram(struct kmsg_dumper *dumper,
> unsigned int err_type = ERR_TYPE_KERNEL_PANIC_GZ;
> int rc = -1;
>
> - switch (reason) {
> + switch (detail->reason) {
> case KMSG_DUMP_SHUTDOWN:
> /* These are almost always orderly shutdowns. */
> return;
> @@ -671,7 +671,7 @@ static void oops_to_nvram(struct kmsg_dumper *dumper,
> break;
> default:
> pr_err("%s: ignoring unrecognized KMSG_DUMP_* reason %d\n",
> - __func__, (int) reason);
> + __func__, (int) detail->reason);
> return;
> }
>
> diff --git a/arch/powerpc/platforms/powernv/opal-kmsg.c b/arch/powerpc/platforms/powernv/opal-kmsg.c
> index 6c3bc4b4da98..bb4218fa796e 100644
> --- a/arch/powerpc/platforms/powernv/opal-kmsg.c
> +++ b/arch/powerpc/platforms/powernv/opal-kmsg.c
> @@ -20,13 +20,13 @@
> * message, it just ensures that OPAL completely flushes the console buffer.
> */
> static void kmsg_dump_opal_console_flush(struct kmsg_dumper *dumper,
> - enum kmsg_dump_reason reason)
> + struct kmsg_dump_detail *detail)
> {
> /*
> * Outside of a panic context the pollers will continue to run,
> * so we don't need to do any special flushing.
> */
> - if (reason != KMSG_DUMP_PANIC)
> + if (detail->reason != KMSG_DUMP_PANIC)
> return;
>
> opal_flush_console(0);
> diff --git a/arch/um/kernel/kmsg_dump.c b/arch/um/kernel/kmsg_dump.c
> index 4382cf02a6d1..419021175272 100644
> --- a/arch/um/kernel/kmsg_dump.c
> +++ b/arch/um/kernel/kmsg_dump.c
> @@ -8,7 +8,7 @@
> #include <os.h>
>
> static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
> - enum kmsg_dump_reason reason)
> + struct kmsg_dump_detail *detail)
> {
> static struct kmsg_dump_iter iter;
> static DEFINE_SPINLOCK(lock);
> diff --git a/drivers/gpu/drm/drm_panic.c b/drivers/gpu/drm/drm_panic.c
> index 948aed00595e..8794c7f6c0ee 100644
> --- a/drivers/gpu/drm/drm_panic.c
> +++ b/drivers/gpu/drm/drm_panic.c
> @@ -655,11 +655,11 @@ static struct drm_plane *to_drm_plane(struct kmsg_dumper *kd)
> return container_of(kd, struct drm_plane, kmsg_panic);
> }
>
> -static void drm_panic(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason)
> +static void drm_panic(struct kmsg_dumper *dumper, struct kmsg_dump_detail *detail)
> {
> struct drm_plane *plane = to_drm_plane(dumper);
>
> - if (reason == KMSG_DUMP_PANIC)
> + if (detail->reason == KMSG_DUMP_PANIC)
> draw_panic_plane(plane);
> }
>
> diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
> index 9c452bfbd571..7a35c82976e0 100644
> --- a/drivers/hv/hv_common.c
> +++ b/drivers/hv/hv_common.c
> @@ -207,13 +207,13 @@ static int hv_die_panic_notify_crash(struct notifier_block *self,
> * buffer and call into Hyper-V to transfer the data.
> */
> static void hv_kmsg_dump(struct kmsg_dumper *dumper,
> - enum kmsg_dump_reason reason)
> + struct kmsg_dump_detail *detail)
> {
> struct kmsg_dump_iter iter;
> size_t bytes_written;
>
> /* We are only interested in panics. */
> - if (reason != KMSG_DUMP_PANIC || !sysctl_record_panic_msg)
> + if (detail->reason != KMSG_DUMP_PANIC || !sysctl_record_panic_msg)
> return;
>
> /*
> diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c
> index 2f11585b5613..86d49db9196d 100644
> --- a/drivers/mtd/mtdoops.c
> +++ b/drivers/mtd/mtdoops.c
> @@ -298,7 +298,7 @@ static void find_next_position(struct mtdoops_context *cxt)
> }
>
> static void mtdoops_do_dump(struct kmsg_dumper *dumper,
> - enum kmsg_dump_reason reason)
> + struct kmsg_dump_detail *detail)
> {
> struct mtdoops_context *cxt = container_of(dumper,
> struct mtdoops_context, dump);
> diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
> index 3497ede88aa0..9c6b7c97fa3c 100644
> --- a/fs/pstore/platform.c
> +++ b/fs/pstore/platform.c
> @@ -275,7 +275,7 @@ void pstore_record_init(struct pstore_record *record,
> * end of the buffer.
> */
> static void pstore_dump(struct kmsg_dumper *dumper,
> - enum kmsg_dump_reason reason)
> + struct kmsg_dump_detail *detail)
> {
> struct kmsg_dump_iter iter;
> unsigned long total = 0;
> @@ -285,9 +285,9 @@ static void pstore_dump(struct kmsg_dumper *dumper,
> int saved_ret = 0;
> int ret;
>
> - why = kmsg_dump_reason_str(reason);
> + why = kmsg_dump_reason_str(detail->reason);
>
> - if (pstore_cannot_block_path(reason)) {
> + if (pstore_cannot_block_path(detail->reason)) {
> if (!spin_trylock_irqsave(&psinfo->buf_lock, flags)) {
> pr_err("dump skipped in %s path because of concurrent dump\n",
> in_nmi() ? "NMI" : why);
> @@ -311,7 +311,7 @@ static void pstore_dump(struct kmsg_dumper *dumper,
> pstore_record_init(&record, psinfo);
> record.type = PSTORE_TYPE_DMESG;
> record.count = oopscount;
> - record.reason = reason;
> + record.reason = detail->reason;
> record.part = part;
> record.buf = psinfo->buf;
>
> @@ -352,7 +352,7 @@ static void pstore_dump(struct kmsg_dumper *dumper,
> }
>
> ret = psinfo->write(&record);
> - if (ret == 0 && reason == KMSG_DUMP_OOPS) {
> + if (ret == 0 && detail->reason == KMSG_DUMP_OOPS) {
> pstore_new_entry = 1;
> pstore_timer_kick();
> } else {
> diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h
> index 906521c2329c..65f5a47727bc 100644
> --- a/include/linux/kmsg_dump.h
> +++ b/include/linux/kmsg_dump.h
> @@ -39,6 +39,17 @@ struct kmsg_dump_iter {
> u64 next_seq;
> };
>
> +/**
> + *struct kmsg_dump_detail - kernel crash detail
> + * @reason: reason for the crash, see kmsg_dump_reason.
> + * @description: optional short string, to provide additional information.
> + */
> +
> +struct kmsg_dump_detail {
> + enum kmsg_dump_reason reason;
> + const char *description;
> +};
> +
> /**
> * struct kmsg_dumper - kernel crash message dumper structure
> * @list: Entry in the dumper list (private)
> @@ -49,13 +60,13 @@ struct kmsg_dump_iter {
> */
> struct kmsg_dumper {
> struct list_head list;
> - void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason);
> + void (*dump)(struct kmsg_dumper *dumper, struct kmsg_dump_detail *detail);
> enum kmsg_dump_reason max_reason;
> bool registered;
> };
>
> #ifdef CONFIG_PRINTK
> -void kmsg_dump(enum kmsg_dump_reason reason);
> +void kmsg_dump_desc(enum kmsg_dump_reason reason, const char *desc);
>
> bool kmsg_dump_get_line(struct kmsg_dump_iter *iter, bool syslog,
> char *line, size_t size, size_t *len);
> @@ -71,7 +82,7 @@ int kmsg_dump_unregister(struct kmsg_dumper *dumper);
>
> const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason);
> #else
> -static inline void kmsg_dump(enum kmsg_dump_reason reason)
> +static inline void kmsg_dump_desc(enum kmsg_dump_reason reason, const char *desc)
> {
> }
>
> @@ -107,4 +118,9 @@ static inline const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason)
> }
> #endif
>
> +static inline void kmsg_dump(enum kmsg_dump_reason reason)
> +{
> + kmsg_dump_desc(reason, NULL);
> +}
> +
> #endif /* _LINUX_KMSG_DUMP_H */
> diff --git a/kernel/panic.c b/kernel/panic.c
> index 0843a275531a..0a8b29c44f3c 100644
> --- a/kernel/panic.c
> +++ b/kernel/panic.c
> @@ -378,7 +378,7 @@ void panic(const char *fmt, ...)
>
> panic_print_sys_info(false);
>
> - kmsg_dump(KMSG_DUMP_PANIC);
> + kmsg_dump_desc(KMSG_DUMP_PANIC, buf);
>
> /*
> * If you doubt kdump always works fine in any situation,
> diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
> index 5dcc05e1aa56..19bc414be5f0 100644
> --- a/kernel/printk/printk.c
> +++ b/kernel/printk/printk.c
> @@ -4272,16 +4272,21 @@ const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason)
> EXPORT_SYMBOL_GPL(kmsg_dump_reason_str);
>
> /**
> - * kmsg_dump - dump kernel log to kernel message dumpers.
> + * kmsg_dump_desc - dump kernel log to kernel message dumpers.
> * @reason: the reason (oops, panic etc) for dumping
> + * @desc: a short string to describe what caused the panic or oops. Can be NULL
> + * if no additional description is available.
> *
> * Call each of the registered dumper's dump() callback, which can
> * retrieve the kmsg records with kmsg_dump_get_line() or
> * kmsg_dump_get_buffer().
> */
> -void kmsg_dump(enum kmsg_dump_reason reason)
> +void kmsg_dump_desc(enum kmsg_dump_reason reason, const char *desc)
> {
> struct kmsg_dumper *dumper;
> + struct kmsg_dump_detail detail = {
> + .reason = reason,
> + .description = desc};
>
> rcu_read_lock();
> list_for_each_entry_rcu(dumper, &dump_list, list) {
> @@ -4299,7 +4304,7 @@ void kmsg_dump(enum kmsg_dump_reason reason)
> continue;
>
> /* invoke dumper which will iterate over records */
> - dumper->dump(dumper, reason);
> + dumper->dump(dumper, &detail);
> }
> rcu_read_unlock();
> }
>
> base-commit: 82e4255305c554b0bb18b7ccf2db86041b4c8b6e
Gentle ping, I need reviews from powerpc, usermod linux, mtd, pstore and
hyperv, to be able to push it in the drm-misc tree.
Best regards,
--
Jocelyn
On July 12, 2024 2:59:30 AM PDT, Jocelyn Falempe <jfalempe@redhat.com> wrote: >Gentle ping, I need reviews from powerpc, usermod linux, mtd, pstore and hyperv, to be able to push it in the drm-misc tree. Oops, I thought I'd Acked already! Acked-by: Kees Cook <kees@kernel.org> And, yeah, as mpe said, you're all good to take this via drm-misc. Thanks! -Kees -- Kees Cook
On 12/07/2024 15:34, Kees Cook wrote: > > > On July 12, 2024 2:59:30 AM PDT, Jocelyn Falempe <jfalempe@redhat.com> wrote: >> Gentle ping, I need reviews from powerpc, usermod linux, mtd, pstore and hyperv, to be able to push it in the drm-misc tree. > > Oops, I thought I'd Acked already! > > Acked-by: Kees Cook <kees@kernel.org> > > And, yeah, as mpe said, you're all good to take this via drm-misc. Thanks a lot. If there is no objection I will push it to drm-misc mid next week. I may have all required acks by then. > > Thanks! > > -Kees > > Best regards, -- Jocelyn
Jocelyn Falempe <jfalempe@redhat.com> writes: > On 02/07/2024 14:26, Jocelyn Falempe wrote: >> kmsg_dump doesn't forward the panic reason string to the kmsg_dumper >> callback. >> This patch adds a new struct kmsg_dump_detail, that will hold the >> reason and description, and pass it to the dump() callback. >> >> To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc() >> function and a macro for backward compatibility. >> >> I've written this for drm_panic, but it can be useful for other >> kmsg_dumper. >> It allows to see the panic reason, like "sysrq triggered crash" >> or "VFS: Unable to mount root fs on xxxx" on the drm panic screen. >> >> v2: >> * Use a struct kmsg_dump_detail to hold the reason and description >> pointer, for more flexibility if we want to add other parameters. >> (Kees Cook) >> * Fix powerpc/nvram_64 build, as I didn't update the forward >> declaration of oops_to_nvram() >> >> Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com> >> --- >> arch/powerpc/kernel/nvram_64.c | 8 ++++---- >> arch/powerpc/platforms/powernv/opal-kmsg.c | 4 ++-- >> arch/um/kernel/kmsg_dump.c | 2 +- >> drivers/gpu/drm/drm_panic.c | 4 ++-- >> drivers/hv/hv_common.c | 4 ++-- >> drivers/mtd/mtdoops.c | 2 +- >> fs/pstore/platform.c | 10 +++++----- >> include/linux/kmsg_dump.h | 22 +++++++++++++++++++--- >> kernel/panic.c | 2 +- >> kernel/printk/printk.c | 11 ++++++++--- >> 10 files changed, 45 insertions(+), 24 deletions(-) > ... > Gentle ping, I need reviews from powerpc, usermod linux, mtd, pstore and > hyperv, to be able to push it in the drm-misc tree. For a simple mechanical change like that you don't need reviews from every subsystem. As long as it's posted to each subsystem and there's been a bit of time for folks to see it, and the build robots to build it, that should be sufficient. Otherwise you could be waiting forever. cheers
On Tue 2024-07-02 14:26:04, Jocelyn Falempe wrote: > kmsg_dump doesn't forward the panic reason string to the kmsg_dumper > callback. > This patch adds a new struct kmsg_dump_detail, that will hold the > reason and description, and pass it to the dump() callback. > > To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc() > function and a macro for backward compatibility. > > I've written this for drm_panic, but it can be useful for other > kmsg_dumper. > It allows to see the panic reason, like "sysrq triggered crash" > or "VFS: Unable to mount root fs on xxxx" on the drm panic screen. > > v2: > * Use a struct kmsg_dump_detail to hold the reason and description > pointer, for more flexibility if we want to add other parameters. > (Kees Cook) > * Fix powerpc/nvram_64 build, as I didn't update the forward > declaration of oops_to_nvram() > > Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com> Looks good to me. With the minor fixes suggested by Kees: Acked-by: Petr Mladek <pmladek@suse.com> Best Regards, Petr
On Tue, Jul 02, 2024 at 02:26:04PM +0200, Jocelyn Falempe wrote:
> kmsg_dump doesn't forward the panic reason string to the kmsg_dumper
> callback.
> This patch adds a new struct kmsg_dump_detail, that will hold the
> reason and description, and pass it to the dump() callback.
Thanks! I like this much better. :)
>
> To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc()
> function and a macro for backward compatibility.
>
> I've written this for drm_panic, but it can be useful for other
> kmsg_dumper.
> It allows to see the panic reason, like "sysrq triggered crash"
> or "VFS: Unable to mount root fs on xxxx" on the drm panic screen.
>
> v2:
> * Use a struct kmsg_dump_detail to hold the reason and description
> pointer, for more flexibility if we want to add other parameters.
> (Kees Cook)
> * Fix powerpc/nvram_64 build, as I didn't update the forward
> declaration of oops_to_nvram()
The versioning history commonly goes after the "---".
> [...]
> diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h
> index 906521c2329c..65f5a47727bc 100644
> --- a/include/linux/kmsg_dump.h
> +++ b/include/linux/kmsg_dump.h
> @@ -39,6 +39,17 @@ struct kmsg_dump_iter {
> u64 next_seq;
> };
>
> +/**
> + *struct kmsg_dump_detail - kernel crash detail
Is kern-doc happy with this? I think there is supposed to be a space
between the "*" and the first word:
/**
* struct kmsg...
Otherwise looks good to me!
--
Kees Cook
On 02/07/2024 22:29, Kees Cook wrote:
> On Tue, Jul 02, 2024 at 02:26:04PM +0200, Jocelyn Falempe wrote:
>> kmsg_dump doesn't forward the panic reason string to the kmsg_dumper
>> callback.
>> This patch adds a new struct kmsg_dump_detail, that will hold the
>> reason and description, and pass it to the dump() callback.
>
> Thanks! I like this much better. :)
>
>>
>> To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc()
>> function and a macro for backward compatibility.
>>
>> I've written this for drm_panic, but it can be useful for other
>> kmsg_dumper.
>> It allows to see the panic reason, like "sysrq triggered crash"
>> or "VFS: Unable to mount root fs on xxxx" on the drm panic screen.
>>
>> v2:
>> * Use a struct kmsg_dump_detail to hold the reason and description
>> pointer, for more flexibility if we want to add other parameters.
>> (Kees Cook)
>> * Fix powerpc/nvram_64 build, as I didn't update the forward
>> declaration of oops_to_nvram()
>
> The versioning history commonly goes after the "---".
ok, I was not aware of this.
>
>> [...]
>> diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h
>> index 906521c2329c..65f5a47727bc 100644
>> --- a/include/linux/kmsg_dump.h
>> +++ b/include/linux/kmsg_dump.h
>> @@ -39,6 +39,17 @@ struct kmsg_dump_iter {
>> u64 next_seq;
>> };
>>
>> +/**
>> + *struct kmsg_dump_detail - kernel crash detail
>
> Is kern-doc happy with this? I think there is supposed to be a space
> between the "*" and the first word:
>
> /**
> * struct kmsg...
>
>
Good catch, yes there is a space missing.
I just checked with "make htmldocs", and in fact
include/linux/kmsg_dump.h is not indexed for kernel documentation.
And you can't find the definition of struct kmsg_dumper in the online doc.
https://www.kernel.org/doc/html/latest/search.html?q=kmsg_dumper
> Otherwise looks good to me!
>
Thanks.
As this patch touches different subsystems, do you know on which tree it
should land ?
--
Jocelyn
On Wed 2024-07-03 09:57:26, Jocelyn Falempe wrote:
>
>
> On 02/07/2024 22:29, Kees Cook wrote:
> > On Tue, Jul 02, 2024 at 02:26:04PM +0200, Jocelyn Falempe wrote:
> > > kmsg_dump doesn't forward the panic reason string to the kmsg_dumper
> > > callback.
> > > This patch adds a new struct kmsg_dump_detail, that will hold the
> > > reason and description, and pass it to the dump() callback.
> >
> > Thanks! I like this much better. :)
> >
> > >
> > > To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc()
> > > function and a macro for backward compatibility.
> > >
> > > I've written this for drm_panic, but it can be useful for other
> > > kmsg_dumper.
> > > It allows to see the panic reason, like "sysrq triggered crash"
> > > or "VFS: Unable to mount root fs on xxxx" on the drm panic screen.
> > >
> > > v2:
> > > * Use a struct kmsg_dump_detail to hold the reason and description
> > > pointer, for more flexibility if we want to add other parameters.
> > > (Kees Cook)
> > > * Fix powerpc/nvram_64 build, as I didn't update the forward
> > > declaration of oops_to_nvram()
> >
> > The versioning history commonly goes after the "---".
>
> ok, I was not aware of this.
> >
> > > [...]
> > > diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h
> > > index 906521c2329c..65f5a47727bc 100644
> > > --- a/include/linux/kmsg_dump.h
> > > +++ b/include/linux/kmsg_dump.h
> > > @@ -39,6 +39,17 @@ struct kmsg_dump_iter {
> > > u64 next_seq;
> > > };
> > > +/**
> > > + *struct kmsg_dump_detail - kernel crash detail
> >
> > Is kern-doc happy with this? I think there is supposed to be a space
> > between the "*" and the first word:
> >
> > /**
> > * struct kmsg...
> >
> >
> Good catch, yes there is a space missing.
>
> I just checked with "make htmldocs", and in fact include/linux/kmsg_dump.h
> is not indexed for kernel documentation.
> And you can't find the definition of struct kmsg_dumper in the online doc.
> https://www.kernel.org/doc/html/latest/search.html?q=kmsg_dumper
>
> > Otherwise looks good to me!
> >
>
> Thanks.
>
> As this patch touches different subsystems, do you know on which tree it
> should land ?
Andrew usually takes patches against kernel/panic.c.
Or you could take it via the DRM tree, especially if you already have the code
using the string.
Also I could take it via the printk tree. The only complication is
that I am going to be away the following two weeks and would come
back in the middle of the merge window. I do not expect much problems
with this change but...
Best Regards,
Petr
On Wed, Jul 03, 2024 at 10:22:11AM +0200, Petr Mladek wrote:
> On Wed 2024-07-03 09:57:26, Jocelyn Falempe wrote:
> >
> >
> > On 02/07/2024 22:29, Kees Cook wrote:
> > > On Tue, Jul 02, 2024 at 02:26:04PM +0200, Jocelyn Falempe wrote:
> > > > kmsg_dump doesn't forward the panic reason string to the kmsg_dumper
> > > > callback.
> > > > This patch adds a new struct kmsg_dump_detail, that will hold the
> > > > reason and description, and pass it to the dump() callback.
> > >
> > > Thanks! I like this much better. :)
> > >
> > > >
> > > > To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc()
> > > > function and a macro for backward compatibility.
> > > >
> > > > I've written this for drm_panic, but it can be useful for other
> > > > kmsg_dumper.
> > > > It allows to see the panic reason, like "sysrq triggered crash"
> > > > or "VFS: Unable to mount root fs on xxxx" on the drm panic screen.
> > > >
> > > > v2:
> > > > * Use a struct kmsg_dump_detail to hold the reason and description
> > > > pointer, for more flexibility if we want to add other parameters.
> > > > (Kees Cook)
> > > > * Fix powerpc/nvram_64 build, as I didn't update the forward
> > > > declaration of oops_to_nvram()
> > >
> > > The versioning history commonly goes after the "---".
> >
> > ok, I was not aware of this.
> > >
> > > > [...]
> > > > diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h
> > > > index 906521c2329c..65f5a47727bc 100644
> > > > --- a/include/linux/kmsg_dump.h
> > > > +++ b/include/linux/kmsg_dump.h
> > > > @@ -39,6 +39,17 @@ struct kmsg_dump_iter {
> > > > u64 next_seq;
> > > > };
> > > > +/**
> > > > + *struct kmsg_dump_detail - kernel crash detail
> > >
> > > Is kern-doc happy with this? I think there is supposed to be a space
> > > between the "*" and the first word:
> > >
> > > /**
> > > * struct kmsg...
> > >
> > >
> > Good catch, yes there is a space missing.
> >
> > I just checked with "make htmldocs", and in fact include/linux/kmsg_dump.h
> > is not indexed for kernel documentation.
> > And you can't find the definition of struct kmsg_dumper in the online doc.
> > https://www.kernel.org/doc/html/latest/search.html?q=kmsg_dumper
> >
> > > Otherwise looks good to me!
> > >
> >
> > Thanks.
> >
> > As this patch touches different subsystems, do you know on which tree it
> > should land ?
>
> Andrew usually takes patches against kernel/panic.c.
>
> Or you could take it via the DRM tree, especially if you already have the code
> using the string.
>
> Also I could take it via the printk tree. The only complication is
> that I am going to be away the following two weeks and would come
> back in the middle of the merge window. I do not expect much problems
> with this change but...
If DRM doesn't want to carry it, I can put it in through the pstore
tree. Let me know! :)
--
Kees Cook
On 03/07/2024 18:27, Kees Cook wrote:
> On Wed, Jul 03, 2024 at 10:22:11AM +0200, Petr Mladek wrote:
>> On Wed 2024-07-03 09:57:26, Jocelyn Falempe wrote:
>>>
>>>
>>> On 02/07/2024 22:29, Kees Cook wrote:
>>>> On Tue, Jul 02, 2024 at 02:26:04PM +0200, Jocelyn Falempe wrote:
>>>>> kmsg_dump doesn't forward the panic reason string to the kmsg_dumper
>>>>> callback.
>>>>> This patch adds a new struct kmsg_dump_detail, that will hold the
>>>>> reason and description, and pass it to the dump() callback.
>>>>
>>>> Thanks! I like this much better. :)
>>>>
>>>>>
>>>>> To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc()
>>>>> function and a macro for backward compatibility.
>>>>>
>>>>> I've written this for drm_panic, but it can be useful for other
>>>>> kmsg_dumper.
>>>>> It allows to see the panic reason, like "sysrq triggered crash"
>>>>> or "VFS: Unable to mount root fs on xxxx" on the drm panic screen.
>>>>>
>>>>> v2:
>>>>> * Use a struct kmsg_dump_detail to hold the reason and description
>>>>> pointer, for more flexibility if we want to add other parameters.
>>>>> (Kees Cook)
>>>>> * Fix powerpc/nvram_64 build, as I didn't update the forward
>>>>> declaration of oops_to_nvram()
>>>>
>>>> The versioning history commonly goes after the "---".
>>>
>>> ok, I was not aware of this.
>>>>
>>>>> [...]
>>>>> diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h
>>>>> index 906521c2329c..65f5a47727bc 100644
>>>>> --- a/include/linux/kmsg_dump.h
>>>>> +++ b/include/linux/kmsg_dump.h
>>>>> @@ -39,6 +39,17 @@ struct kmsg_dump_iter {
>>>>> u64 next_seq;
>>>>> };
>>>>> +/**
>>>>> + *struct kmsg_dump_detail - kernel crash detail
>>>>
>>>> Is kern-doc happy with this? I think there is supposed to be a space
>>>> between the "*" and the first word:
>>>>
>>>> /**
>>>> * struct kmsg...
>>>>
>>>>
>>> Good catch, yes there is a space missing.
>>>
>>> I just checked with "make htmldocs", and in fact include/linux/kmsg_dump.h
>>> is not indexed for kernel documentation.
>>> And you can't find the definition of struct kmsg_dumper in the online doc.
>>> https://www.kernel.org/doc/html/latest/search.html?q=kmsg_dumper
>>>
>>>> Otherwise looks good to me!
>>>>
>>>
>>> Thanks.
>>>
>>> As this patch touches different subsystems, do you know on which tree it
>>> should land ?
>>
>> Andrew usually takes patches against kernel/panic.c.
>>
>> Or you could take it via the DRM tree, especially if you already have the code
>> using the string.
If it's not taken in Andrew's tree next week, I will see if I can push
it to the drm-misc tree. I think there is a very low chance of conflicts.
>>
>> Also I could take it via the printk tree. The only complication is
>> that I am going to be away the following two weeks and would come
>> back in the middle of the merge window. I do not expect much problems
>> with this change but...
>
> If DRM doesn't want to carry it, I can put it in through the pstore
> tree. Let me know! :)
>
Thanks for the proposition, I will see how it goes, it would be nice to
have it in time for the v6.11 merge window.
Best regards,
--
Jocelyn
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