6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Michael Kelley <mhklinux@xxxxxxxxxxx>
[ Upstream commit 7241c886a71797cc51efc6fadec7076fcf6435c2 ]
When a Hyper-V framebuffer device is removed, or the driver is unbound
from a device, any allocated and/or mapped memory must be released. In
particular, MMIO address space that was mapped to the framebuffer must
be unmapped. Current code unmaps the wrong address, resulting in an
error like:
[ 4093.980597] iounmap: bad address 00000000c936c05c
followed by a stack dump.
Commit d21987d709e8 ("video: hyperv: hyperv_fb: Support deferred IO for
Hyper-V frame buffer driver") changed the kind of address stored in
info->screen_base, and the iounmap() call in hvfb_putmem() was not
updated accordingly.
Fix this by updating hvfb_putmem() to unmap the correct address.
Fixes: d21987d709e8 ("video: hyperv: hyperv_fb: Support deferred IO for Hyper-V frame buffer driver")
Signed-off-by: Michael Kelley <mhklinux@xxxxxxxxxxx>
Reviewed-by: Saurabh Sengar <ssengar@xxxxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20250209235252.2987-1-mhklinux@xxxxxxxxxxx
Signed-off-by: Wei Liu <wei.liu@xxxxxxxxxx>
Message-ID: <20250209235252.2987-1-mhklinux@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/video/fbdev/hyperv_fb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c
index b9965cbdd7642..80e8ec36b7db2 100644
--- a/drivers/video/fbdev/hyperv_fb.c
+++ b/drivers/video/fbdev/hyperv_fb.c
@@ -1106,7 +1106,7 @@ static void hvfb_putmem(struct hv_device *hdev, struct fb_info *info)
if (par->need_docopy) {
vfree(par->dio_vp);
- iounmap(info->screen_base);
+ iounmap(par->mmio_vp);
vmbus_free_mmio(par->mem->start, screen_fb_size);
} else {
hvfb_release_phymem(hdev, info->fix.smem_start,
--
2.39.5
