Re: [PATCH 01/15] taint: add module firmware crash taint support

On 5/9/20 9:46 AM, Luis Chamberlain wrote:

On Sat, May 09, 2020 at 11:18:29AM -0400, Rafael Aquini wrote:

quoted

We are still missing the documentation bits for this
new flag, though.

Ah yeah sorry about that.

quoted

How about having a blurb similar to:

diff --git a/Documentation/admin-guide/tainted-kernels.rst b/Documentation/admin-guide/tainted-kernels.rst
index 71e9184a9079..5c6a9e2478b0 100644
--- a/Documentation/admin-guide/tainted-kernels.rst
+++ b/Documentation/admin-guide/tainted-kernels.rst

@@ -100,6 +100,7 @@ Bit  Log  Number  Reason that got the kernel tainted
  15  _/K   32768  kernel has been live patched
  16  _/X   65536  auxiliary taint, defined for and used by distros
  17  _/T  131072  kernel was built with the struct randomization plugin
+ 18  _/Q  262144  driver firmware crash annotation
 ===  ===  ======  ========================================================

 Note: The character ``_`` is representing a blank in this table to make reading

@@ -162,3 +163,7 @@ More detailed explanation for tainting
      produce extremely unusual kernel structure layouts (even performance
      pathological ones), which is important to know when debugging. Set at
      build time.
+
+ 18) ``Q`` Device drivers might annotate the kernel with this taint, in cases
+     their firmware might have crashed leaving the driver in a crippled and
+     potentially useless state.

Sure, I'll modify it a bit to add the use case to help with support
issues, ie, to help rule out firmware issues.

Please also update tools/debugging/kernel-chktaint.

I'm starting to think that to make this even more usesul later we may
want to add a uevent to add_taint() so that userspace can decide to look
into this, ignore it, or report something to the user, say on their
desktop.

thanks.
-- 
~Randy