[reactos] 01/01: [FREELDR] Workaround regression CORE-16469

[Joachim Henze]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=7c81fb8f568c0dc875018…

commit 7c81fb8f568c0dc875018fa382d215c088eb839d
Author:     Joachim Henze <Joachim.Henze(a)reactos.org>
AuthorDate: Wed May 6 23:44:50 2020 +0200
Commit:     Joachim Henze <Joachim.Henze(a)reactos.org>
CommitDate: Wed May 6 23:45:37 2020 +0200

    [FREELDR] Workaround regression CORE-16469
    
    This prevents ReactOS asserting when 'My computer'
    is opened, while it tries to send commands to floppy drive.
    
    Many thanks to patches author Doug Lyons.
    
    The regression was introduced by 0.4.13-dev-1081-g
    eeff926ede1b2109bb0e129a960b74f3261cf2f1
    
    patch was committed to 0.4.13rls and 0.4.14rls as well.
    
    Today it was committed to master as well, as
    the initially planned investigation for the root cause
    did still not happen and we can not afford the time
    to retest and workaround this over and over again.
    Thank god that Oleg Dubinskiy was still around to retest
    this again and confirmed it can still happen, because
    unlike initially, personally I was not able to reproduce it
    today anymore!
    
    Since every release was work-arounded, we did never
    expose the bug in any final release.
---
 boot/freeldr/freeldr/arch/i386/pc/pcdisk.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/boot/freeldr/freeldr/arch/i386/pc/pcdisk.c
b/boot/freeldr/freeldr/arch/i386/pc/pcdisk.c
index 37058bced70..550c424d15d 100644
--- a/boot/freeldr/freeldr/arch/i386/pc/pcdisk.c
+++ b/boot/freeldr/freeldr/arch/i386/pc/pcdisk.c
@@ -790,7 +790,7 @@ PcDiskReadLogicalSectors(
 #if defined(__i386__) || defined(_M_AMD64)
 VOID __cdecl DiskStopFloppyMotor(VOID)
 {
-    WRITE_PORT_UCHAR((PUCHAR)0x3F2, 0x0C); // DOR_FDC_ENABLE |
DOR_DMA_IO_INTERFACE_ENABLE
+    WRITE_PORT_UCHAR((PUCHAR)0x3F2, 0); // DOR_FDC_ENABLE | DOR_DMA_IO_INTERFACE_ENABLE
0x0C // we changed 0x0C->0 to workaround CORE-16469
 }
 #endif // defined __i386__ || defined(_M_AMD64)