New subject: [ros-diffs] [dgorbachev] 42305: Add a hack in KiSystemStartupReal function until Better Times.

30 Jul 2009

That function is not supposed to be called by old bootloader  
directly. Why is that needed? And why in this function?

WBR,
Aleksey Bragin.

On Jul 30, 2009, at 9:54 PM, dgorbachev(a)svn.reactos.org wrote:

...
  Author: dgorbachev
 Date: Thu Jul 30 19:54:01 2009
 New Revision: 42305

 URL: http://svn.reactos.org/svn/reactos?rev=42305&view=rev
 Log:
 Add a hack in KiSystemStartupReal function until Better Times.

 Modified:
     trunk/reactos/ntoskrnl/ke/i386/kiinit.c

 Modified: trunk/reactos/ntoskrnl/ke/i386/kiinit.c
 URL: http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/ke/ 
 i386/kiinit.c?rev=42305&r1=42304&r2=42305&view=diff
 ====================================================================== 
 ========
 --- trunk/reactos/ntoskrnl/ke/i386/kiinit.c [iso-8859-1] (original)
 +++ trunk/reactos/ntoskrnl/ke/i386/kiinit.c [iso-8859-1] Thu Jul 30  
 19:54:01 2009
 @@ -712,18 +712,34 @@
      Ke386SetDs(KGDT_R3_DATA | RPL_MASK);
      Ke386SetEs(KGDT_R3_DATA | RPL_MASK);

 -    /* Save NMI and double fault traps */
 -    RtlCopyMemory(&NmiEntry, &Idt[2], sizeof(KIDTENTRY));
 -    RtlCopyMemory(&DoubleFaultEntry, &Idt[8], sizeof(KIDTENTRY));
 -
 -    /* Copy kernel's trap handlers */
 -    RtlCopyMemory(Idt,
 -                  (PVOID)KiIdtDescriptor.Base,
 -                  KiIdtDescriptor.Limit + 1);
 -
 -    /* Restore NMI and double fault */
 -    RtlCopyMemory(&Idt[2], &NmiEntry, sizeof(KIDTENTRY));
 -    RtlCopyMemory(&Idt[8], &DoubleFaultEntry, sizeof(KIDTENTRY));
 +    /* HACK compensates for KiRosPrepareForSystemStartup hack */
 +    if ((ULONG)Idt == KiIdtDescriptor.Base)
 +    {
 +        USHORT FlippedSelector;
 +
 +        FlippedSelector = KiIdt[2].Selector;
 +        KiIdt[2].Selector = KiIdt[2].ExtendedOffset;
 +        KiIdt[2].ExtendedOffset = FlippedSelector;
 +
 +        FlippedSelector = KiIdt[8].Selector;
 +        KiIdt[8].Selector = KiIdt[8].ExtendedOffset;
 +        KiIdt[8].ExtendedOffset = FlippedSelector;
 +    }
 +    else
 +    {
 +        /* Save NMI and double fault traps */
 +        RtlCopyMemory(&NmiEntry, &Idt[2], sizeof(KIDTENTRY));
 +        RtlCopyMemory(&DoubleFaultEntry, &Idt[8], sizeof(KIDTENTRY));
 +
 +        /* Copy kernel's trap handlers */
 +        RtlCopyMemory(Idt,
 +                      (PVOID)KiIdtDescriptor.Base,
 +                      KiIdtDescriptor.Limit + 1);
 +
 +        /* Restore NMI and double fault */
 +        RtlCopyMemory(&Idt[2], &NmiEntry, sizeof(KIDTENTRY));
 +        RtlCopyMemory(&Idt[8], &DoubleFaultEntry, sizeof(KIDTENTRY));
 +    }

  AppCpuInit:
      /* Loop until we can release the freeze lock */

Re: [ros-dev] [ros-diffs] [dgorbachev] 42305: Add a hack in KiSystemStartupReal function until Better Times.