linux-kernel - Indirect call in vesafb driver

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Date:   Wed, 13 Mar 2019 17:54:18 +0300
From:   Alexander Pateenok <pateenoc@...il.com>
To:     Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>,
        dri-devel@...ts.freedesktop.org, linux-fbdev@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Indirect call in vesafb driver

Hi,

There're several indirect calls in inline assembly in vesafb driver
(drivers/video/fbdev/vesafb.c), and these calls cannot be automatically
changed to retpolines. It's in vesafb_pan_display():

   73        __asm__ __volatile__(
   74                "call *(%%edi)"

and in vesa_setpalette():

  113        __asm__ __volatile__(
  114         "call *(%%esi)"

Is there need to use CALL_NOSPEC ?

Thanks, Alex