Fixes to memory management that helps me sleep at night.

sortix/elf.cpp

@@ -35,15 +35,6 @@ namespace Sortix
 {
 	namespace ELF
 	{
-		// This works around an optimizer bug I ran into, where the memcpy below
-		// somehow gets executed prior to the memory was mapped. Somehow, when I
-		// tried to debug it, it suddenly worked. So here's some deep magic that
-		// somehow fixes my code.
-		void PreventHazardousCodeReordering()
-		{
-			Log::Print("");
-		}
-
 		addr_t Construct32(Process* process, const void* file, size_t filelen)
 		{
 			if ( filelen < sizeof(Header32) ) { return 0; }
@@ -70,6 +61,10 @@ namespace Sortix
 			// Reset the current address space.
 			process->ResetAddressSpace();
 
+			// Flush the TLB such that no stale information from the last
+			// address space is used when creating the new one.
+			Memory::Flush();
+
 			// Create all the segments in the final process.
 			// TODO: Handle errors on bad/malicious input or out-of-mem!
 			for ( uint16_t i = 0; i < numprogheaders; i++ )
@@ -94,7 +89,7 @@ namespace Sortix
 					return 0;
 				}
 
-				if ( !Memory::MapRangeUser(mapto, mapbytes) )
+				if ( !Memory::MapRangeUser(mapto, mapbytes))
 				{
 					return 0;
 				}
@@ -105,8 +100,6 @@ namespace Sortix
 				segment->next = process->segments;
 				process->segments = segment;
 
-				PreventHazardousCodeReordering();
-
 				// Copy as much data as possible and memset the rest to 0.
 				byte* memdest = (byte*) virtualaddr;
 				byte* memsource = (byte*) ( ((addr_t)file) + pht->offset);

sortix/x86-family/memorymanagement.cpp

@@ -66,7 +66,7 @@ namespace Sortix
 
 			// Loop over every detected memory region.
 			for	(
-                 mmap_t mmap = (mmap_t) bootinfo->mmap_addr;
+				 mmap_t mmap = (mmap_t) bootinfo->mmap_addr;
 				 (addr_t) mmap < bootinfo->mmap_addr + bootinfo->mmap_length;
 				 mmap = (mmap_t) ((addr_t) mmap + mmap->size + sizeof(mmap->size))
 				)
@@ -425,20 +425,10 @@ namespace Sortix
 
 			while ( positionstack[TOPPMLLEVEL] < ENTRIES )
 			{
-				if ( level == 1 )
-				{
-					//Log::PrintF("[%zu > %zu]", positionstack[2], positionstack[1]);
-				}
-				else
-				{
-					//Log::PrintF("[%zu]", positionstack[2]);
-				}
-
 				const size_t pos = positionstack[level];
 
 				if ( pos == ENTRIES )
 				{
-					//Log::PrintF(" done with level\n");
 					(positionstack[++level])++;
 					pmloffset /= ENTRIES;
 					continue;
@@ -454,7 +444,6 @@ namespace Sortix
 
 					if ( unlikely(phys == 0) )
 					{
-						//Log::PrintF(" out of memory!\n");
 						// Oh no. Out of memory! We'll have to undo everything
 						// we just did. Argh!
 						failure = true;
@@ -472,8 +461,6 @@ namespace Sortix
 
 					if ( level == 1 )
 					{
-						//Log::PrintF(" copy\n");
-
 						// Determine the source page's address.
 						const void* src = (const void*) (pmloffset * 4096UL);
 
@@ -484,8 +471,6 @@ namespace Sortix
 					}
 					else
 					{
-						//Log::PrintF(" recurse\n");
-
 						// Fork the PML recursively!
 						pmloffset = pmloffset * ENTRIES + pos;
 						positionstack[--level] = 0;
@@ -496,15 +481,12 @@ namespace Sortix
 				// If this entry should be linked, link it.
 				else
 				{
-					//Log::PrintF(" link\n");
 					FORKPML[level].entry[pos] = entry;
 				}
 
 				positionstack[level]++;
 			}
 
-			//Log::PrintF("Fork: Loop Terminated\n");
-
 			if ( !failure )
 			{
 				// Now, the new top pml needs to have its fractal memory fixed.
@@ -524,8 +506,6 @@ namespace Sortix
 					childaddr = (FORKPML + i)->entry[ENTRIES-2] & PML_ADDRESS;
 				}
 
-				//Log::PrintF("Fork: Done\n");
-
 				return newtoppmladdr;
 			}