patch "Revert "video: imsttfb: fix potential NULL pointer dereferences"" added to char-misc-linus

This is a note to let you know that I've just added the patch titled

Revert "video: imsttfb: fix potential NULL pointer dereferences"

to my char-misc git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.

If you have any questions about this process, please let me know.

From ed04fe8a0e87d7b5ea17d47f4ac9ec962b24814a Mon Sep 17 00:00:00 2001
From: Greg Kroah-Hartman <[email protected]>
Date: Mon, 3 May 2021 13:57:33 +0200
Subject: Revert "video: imsttfb: fix potential NULL pointer dereferences"

This reverts commit 1d84353d205a953e2381044953b7fa31c8c9702d.

Because of recent interactions with developers from @umn.edu, all commits from them have been recently re-reviewed to ensure if they were correct or not.

Upon review, this commit was found to be incorrect for the reasons below, so it must be reverted. It will be fixed up "correctly" in a later kernel change.

The original commit here, while technically correct, did not fully handle all of the reported issues that the commit stated it was fixing, so revert it until it can be "fixed" fully.

Note, ioremap() probably will never fail for old hardware like this, and if anyone actually used this hardware (a PowerMac era PCI display card), they would not be using fbdev anymore.

---
 drivers/video/fbdev/imsttfb.c | 5 -----
 1 file changed, 5 deletions(-)

index 3ac053b88495..e04411701ec8 100644
@@ -1512,11 +1512,6 @@ static int imsttfb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	info->fix.smem_start = addr;
 	info->screen_base = (__u8 *)ioremap(addr, par->ramdac == IBM ?
 					    0x400000 : 0x800000);
-	if (!info->screen_base) {
-		release_mem_region(addr, size);
-		framebuffer_release(info);
-		return -ENOMEM;
-	}
 	info->fix.mmio_start = addr + 0x800000;
 	par->dc_regs = ioremap(addr + 0x800000, 0x1000);
 	par->cmap_regs_phys = addr + 0x840000;

2.31.1