Re: Indirect call in vesafb driver
On Tue, Mar 19, 2019 at 04:46:51PM +, Alan Cox wrote: > On Wed, 13 Mar 2019 17:54:18 +0300 > Alexander Pateenok wrote: > > > 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 ? > > Vesafb is from the time on the dinosaurs but yes any vesa bios code will > not be speculatively hardened. I'd also doubt anyone is actually using > vesafb in the first place but it should use nospec Note that even when using vesafb the display panning is disabled by default, and vesa_setpalette() is only used with 8bit depth (256 color mode). Also note that only 32bit builds will try to call vesa bios code ... cheers, Gerd ___ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
Re: Indirect call in vesafb driver
On Wed, 13 Mar 2019 17:54:18 +0300 Alexander Pateenok wrote: > 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 ? Vesafb is from the time on the dinosaurs but yes any vesa bios code will not be speculatively hardened. I'd also doubt anyone is actually using vesafb in the first place but it should use nospec Alan ___ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
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 ___ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
