Hi Greg,
On 12/17/2025 5:34 PM, Greg Kroah-Hartman wrote:
On Wed, Dec 17, 2025 at 05:45:30PM +0800, Gu Bowen wrote:
This issue has already been fixed by commit eabb03293087 ("fbdev:
Refactoring the fbcon packed pixel drawing routines") on v6.15-rc1, but it
still exists in the stable version.
Why not take the refactoring changes instead? That is almost always the
proper thing to do, one-off changes are almost always wrong and cause
extra work in the long-term.
Please try backporting those changes instead please.
thanks,
greg k-h
As you've suggested, I understand the preference to keep stable branches
aligned with upstream when possible. However, I find that the
refactoring touches many areas of the codebase that have diverged
between mainline and stable-6.6, resulting in extensive merge conflicts.
In addition, I cannot be certain that backporting 3000+ lines of
refactoring code to a stable branch might introduce unknown risks.
Given the current situation, I have another simpler patch solution that
is easy to maintain, and perhaps it could be merged into the stable branch:
void sys_fillrect(struct fb_info *p, const struct fb_fillrect *rect)
...
while (height--) {
dst += dst_idx >> (ffs(bits) - 1);
+ long dst_offset;
+ dst_offset = (unsigned long)dst - (unsigned long)p->screen_base;
+ if (dst_offset < 0 || dst_offset >= p->fix.smem_len)
+ return;
dst_idx &= (bits - 1);
fill_op32(p, dst, dst_idx, pat, width*bpp, bits);
...
BR,
Guber
