On 10/20/26 18:46, Tingjie Zhong wrote:
Commit 3637d34b35b2 ("fbdev: Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds") made bit_putcs() clip glyphs to var.yres. When fbcon scrolls by panning, it draws text rows up to var.yres_virtual, so after the first pan most new text is not drawn until the next full redraw. This affects fbdev drivers that set FBINFO_HWACCEL_YPAN or FBINFO_HWACCEL_YWRAP, such as vesafb with the ypan option, when CONFIG_FRAMEBUFFER_CONSOLE_LEGACY_ACCELERATION=y.Clip to GETVYRES() instead, which fbcon_ud.c and fbcon_ccw.c already use as the drawing area height. When fbcon does not pan, GETVYRES() returns var.yres, keeping the existing bound. When fbcon pans, it returns var.yres_virtual, which the framebuffer memory must cover anyway for panning to work. Fixes: 3637d34b35b2 ("fbdev: Add bounds checking in bit_putcs to fix vmalloc-out-of-bounds") Reported-by: Thomas Zimmermann <[email protected]> Closes: https://lore.kernel.org/linux-fbdev/[email protected]/ Tested-by: Thomas Zimmermann <[email protected]> Cc: [email protected] Signed-off-by: Tingjie Zhong <[email protected]>
applied now to fbdev/for-next. Thanks! Helge
