Re: [PATCH v2] misc: misc_minor_alloc to use ida for all dynamic/misc dynamic minors

From: Greg KH
Date: Tue Oct 15 2024 - 03:53:08 EST


On Tue, Oct 15, 2024 at 07:02:26AM +0000, Vimal Agrawal wrote:
> misc_minor_alloc was allocating id using ida for minor only in case of
> MISC_DYNAMIC_MINOR but misc_minor_free was always freeing ids
> using ida_free causing a mismatch and following warn:
> > > WARNING: CPU: 0 PID: 159 at lib/idr.c:525 ida_free+0x3e0/0x41f
> > > ida_free called for id=127 which is not allocated.
> > > <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
> ...
> > > [<60941eb4>] ida_free+0x3e0/0x41f
> > > [<605ac993>] misc_minor_free+0x3e/0xbc
> > > [<605acb82>] misc_deregister+0x171/0x1b3
>
> misc_minor_alloc is changed to allocate id from ida for all minors
> falling in the range of dynamic/ misc dynamic minors
>
> Fixes: 0ad35fed618c ("char: misc: Increase the maximum number of dynamic misc devices to 1048448")
> Signed-off-by: Vimal Agrawal <vimal.agrawal@xxxxxxxxxx>
> ---
> drivers/char/misc.c | 35 +++++++++++++++++-----
> lib/Kconfig.debug | 11 +++++++
> lib/Makefile | 1 +
> lib/test_misc_minor.c | 67 +++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 107 insertions(+), 7 deletions(-)
> create mode 100644 lib/test_misc_minor.c
>

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman. You have sent him
a patch that has triggered this response. He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created. Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
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- This looks like a new version of a previously submitted patch, but you
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Please read the section entitled "The canonical patch format" in the
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- You have marked a patch with a "Fixes:" tag for a commit that is in an
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Documentation/process/stable-kernel-rules.rst file for how to resolve
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If you wish to discuss this problem further, or you have questions about
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thanks,

greg k-h's patch email bot