pvpanic: Don't use "proxy" headers

Update header inclusions to follow IWYU (Include What You Use)
principle.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20231221144447.2762077-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

misc/pvpanic: deduplicate common code

pvpanic-mmio.c and pvpanic-pci.c share a lot of code.
Refactor it into pvpanic.c where it doesn't have to be kept in sync
manually and where the core logic can be understood more easily.

No functional change.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20231011-pvpanic-cleanup-v2-1-4b21d56f779f@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

misc/pvpanic: Convert regular spinlock into trylock on panic path

The pvpanic driver relies on panic notifiers to execute a callback
on panic event. Such function is executed in atomic context - the
panic function disables local IRQs, preemption and all other CPUs
that aren't running the panic code.

With that said, it's dangerous to use regular spinlocks in such path,
as introduced by commit b3c0f8774668 ("misc/pvpanic: probe multiple instances").
This patch fixes that by replacing regular spinlocks with the trylock
safer approach.

It also fixes an old comment (about a long gone framebuffer code) and
the notifier priority - we should execute hypervisor notifiers early,
deferring this way the panic action to the hypervisor, as expected by
the users that are setting up pvpanic.

Fixes: b3c0f8774668 ("misc/pvpanic: probe multiple instances")
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Mihai Carabas <mihai.carabas@oracle.com>
Cc: Shile Zhang <shile.zhang@linux.alibaba.com>
Cc: Wang ShaoBo <bobo.shaobowang@huawei.com>
Cc: zhenwei pi <pizhenwei@bytedance.com>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Link: https://lore.kernel.org/r/20220427224924.592546-6-gpiccoli@igalia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pvpanic: Indentation fixes here and there

1) replace double spaces with single;
2) relax line width limitation a bit.

Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210829124354.81653-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pvpanic: Fix typos in the comments

Fix a few spelling typos in the comments.

Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210829124354.81653-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pvpanic: Keep single style across modules

We have different style on where we place module_*() and MODULE_*() macros.
Inherit the style from the original module (now pvpanic-mmio.c).

Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210829124354.81653-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

misc/pvpanic: fix set driver data

Add again dev_set_drvdata(), but this time in devm_pvpanic_probe(), in order
for dev_get_drvdata() to not return NULL.

Fixes: 394febc9d0a6 ("misc/pvpanic: Make 'pvpanic_probe()' resource managed")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mihai Carabas <mihai.carabas@oracle.com>
Link: https://lore.kernel.org/r/1629385946-4584-2-git-send-email-mihai.carabas@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

misc/pvpanic: Remove some dead-code

'pvpanic_remove()' is referenced only by a 'devm_add_action_or_reset()'
call in 'devm_pvpanic_probe()'. So, we know that its parameter is non-NULL.

Axe the unneeded check to save a few lines of code.

Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/8e425618f4042a8ab8366be4d34026972e77bd40.1622911768.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

misc/pvpanic: Make 'pvpanic_probe()' resource managed

Simplify code and turn 'pvpanic_probe()' into a managed resource version.
This simplify callers that don't need to do some clean-up on error in the
probe and on remove.

Update pvpanic-mmio.c and pvpanic-pci.c accordingly.

'pvpanic_remove()' don't need to be exported anymore.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/9212cdc8c1e5c187a2f1129a6190085c2a10d28a.1621665058.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kernel.h: split out panic and oops helpers

kernel.h is being used as a dump for all kinds of stuff for a long time.
Here is the attempt to start cleaning it up by splitting out panic and
oops helpers.

There are several purposes of doing this:
- dropping dependency in bug.h
- dropping a loop by moving out panic_notifier.h
- unload kernel.h from something which has its own domain

At the same time convert users tree-wide to use new headers, although for
the time being include new header back to kernel.h to avoid twisted
indirected includes for existing users.

[akpm@linux-foundation.org: thread_info.h needs limits.h]
[andriy.shevchenko@linux.intel.com: ia64 fix]
Link: https://lkml.kernel.org/r/20210520130557.55277-1-andriy.shevchenko@linux.intel.com

Link: https://lkml.kernel.org/r/20210511074137.33666-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Co-developed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Sebastian Reichel <sre@kernel.org>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Acked-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

misc/pvpanic: Make some symbols static

Fix sparse warnings:

drivers/misc/pvpanic/pvpanic.c:28:18: warning:
symbol 'pvpanic_list' was not declared. Should it be static?
drivers/misc/pvpanic/pvpanic.c:29:12: warning:
symbol 'pvpanic_lock' was not declared. Should it be static?

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20210331121706.15268-1-yuehaibing@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

misc/pvpanic: probe multiple instances

Create the mecahism that allows multiple pvpanic instances to call
pvpanic_probe and receive panic events. A global list will retain all the
mapped addresses where to write panic events.

Signed-off-by: Mihai Carabas <mihai.carabas@oracle.com>
Link: https://lore.kernel.org/r/1616597356-20696-3-git-send-email-mihai.carabas@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

misc/pvpanic: split-up generic and platform dependent code

Split-up generic and platform dependent code in order to be able to re-use
generic event handling code in pvpanic PCI device driver in the next patches.

The code from pvpanic.c was split in two new files:
- pvpanic.c: generic code that handles pvpanic events
- pvpanic-mmio.c: platform/bus dependent code

Signed-off-by: Mihai Carabas <mihai.carabas@oracle.com>
Link: https://lore.kernel.org/r/1616597356-20696-2-git-send-email-mihai.carabas@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>