| Message ID | 20240702122639.248110-1-jfalempe@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] printk: Add a short description string to kmsg_dump() | expand |
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!
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 ?
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 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! :)
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,
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 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
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 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
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,
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,
On 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
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(); }
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(-) base-commit: 82e4255305c554b0bb18b7ccf2db86041b4c8b6e