Date: Sun, 03 Dec 2017 23:58:26 +0000 From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 224069] (Fix included) Use of uninitalized register value in vesa.ko, causing X, text console and suspend/resume to fail Message-ID: <bug-224069-8@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D224069 Bug ID: 224069 Summary: (Fix included) Use of uninitalized register value in vesa.ko, causing X, text console and suspend/resume to fail Product: Base System Version: 11.1-STABLE Hardware: Any OS: Any Status: New Severity: Affects Many People Priority: --- Component: kern Assignee: freebsd-bugs@FreeBSD.org Reporter: sblachmann@gmail.com PROBLEMS: -Switching between X and text console fails, screen is garbled or no video = at all -Resuming after suspend results either in garbled or no video at all ANALYSYS: As I was getting annoyed by so many people affected by the buggy vesa.ko, a= nd felt frustrated that these problems with X, particulartly switching between= X and text console and the failure of suspend/resume to restore the screen, I finally took a look into vesa.ko and found immediately a thing very wrong. In line 515 of /usr/src/sys/dev/fb/vesa.c you see this: /* regs.R_DL =3D STATE_SIZE; */ The DL register contains the subfunction of the BIOS call retrieving the bu= ffer size. It must not be undefined, as it is unpredictable which subfunction wi= ll get called. Thus I wish I knew who has commented out that line for what reason. I think this justifies an explanation. Because, the commenting out of this line caused all these problems, which h= ave done big damage to FreeBSD's reputation regarding its usability as desktop = OS. FIX: Uncomment that line. --=20 You are receiving this mail because: You are the assignee for the bug.=
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