similar to: [PATCH 18/21] i386 Ldt cleanups 2

IA-32 linear address translation is loads of fun. While cleaning up the LDT code, I noticed that kprobes code was very bogus with respect to segment handling. Many, many bugs are fixed here. I chose to combine the three separate functions that try to do linear address conversion into one, nice and working functions. All of the versions had bugs. 1) Taking an int3 from v8086 mode could cause

IA-32 linear address translation is loads of fun. While cleaning up the LDT code, I noticed that kprobes code was very bogus with respect to segment handling. Many, many bugs are fixed here. I chose to combine the three separate functions that try to do linear address conversion into one, nice and working functions. All of the versions had bugs. 1) Taking an int3 from v8086 mode could cause

* zach@vmware.com (zach@vmware.com) wrote: > Make the LDT a desc_struct pointer, since this is what it actually is. I like that plan. > There is code which relies on the fact that LDTs are allocated in page > chunks, and it is both cleaner and more convenient to keep the rather > poorly named "size" variable from the LDT in terms of LDT pages. I noticed it's replaced

* zach@vmware.com (zach@vmware.com) wrote: > Make the LDT a desc_struct pointer, since this is what it actually is. I like that plan. > There is code which relies on the fact that LDTs are allocated in page > chunks, and it is both cleaner and more convenient to keep the rather > poorly named "size" variable from the LDT in terms of LDT pages. I noticed it's replaced

Big cleanup of LDT code. This code has very little type checking and is not frequently used, so I audited the code, added type checking and size optimizations to generate smaller assembly code. I changed the ldt count to be in pages, and converted the char * ldt into a desc_struct. Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.14-zach-work/arch/i386/kernel/ldt.c

Big cleanup of LDT code. This code has very little type checking and is not frequently used, so I audited the code, added type checking and size optimizations to generate smaller assembly code. I changed the ldt count to be in pages, and converted the char * ldt into a desc_struct. Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.14-zach-work/arch/i386/kernel/ldt.c

Add some convenient segment macros to the kernel. This makes the rather obfuscated 'seg & 4' go away. Patch-keys: i386 segment cleanup Patch-base: 2.6.13-rc5-mm1 Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/segment.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/segment.h

Add some convenient segment macros to the kernel. This makes the rather obfuscated 'seg & 4' go away. Patch-keys: i386 segment cleanup Patch-base: 2.6.13-rc5-mm1 Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/segment.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/segment.h

plain text document attachment (xx-paravirt-desc-header.patch) Update the descriptors for an interface with paravirt ops Signed-off-by: Steven Rostedt srostedt@redhat.com Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com> Index: clean-start/include/asm-x86_64/desc.h =================================================================== ---

plain text document attachment (xx-paravirt-desc-header.patch) Update the descriptors for an interface with paravirt ops Signed-off-by: Steven Rostedt srostedt@redhat.com Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com> Index: clean-start/include/asm-x86_64/desc.h =================================================================== ---

Introduce a write acessor for updating the current LDT. This is required for hypervisors like Xen that do not allow LDT pages to be directly written. Testing - here's a fun little LDT test that can be trivially modified to test limits as well. /* * Copyright (c) 2005, Zachary Amsden (zach@vmware.com) * This is licensed under the GPL. */ #include <stdio.h> #include <signal.h>

Introduce a write acessor for updating the current LDT. This is required for hypervisors like Xen that do not allow LDT pages to be directly written. Testing - here's a fun little LDT test that can be trivially modified to test limits as well. /* * Copyright (c) 2005, Zachary Amsden (zach@vmware.com) * This is licensed under the GPL. */ #include <stdio.h> #include <signal.h>

i386 Transparent paravirtualization subarch patch #5 This change encapsulates descriptor and task register management. Diffs against: 2.6.13-rc4-mm1 Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/desc.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/desc.h 2005-08-08 17:31:59.000000000 -0700

i386 Transparent paravirtualization subarch patch #5 This change encapsulates descriptor and task register management. Diffs against: 2.6.13-rc4-mm1 Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/desc.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/desc.h 2005-08-08 17:31:59.000000000 -0700

Descriptor and trap table cleanups. Add cleanly written accessors for IDT and GDT gates so the subarch may override them. Note that this allows the hypervisor to transparently tweak the DPL of the descriptors as well as the RPL of segments in those descriptors, with no unnecessary kernel code modification. It also allows the hypervisor implementation of the VMI to tweak the gates, allowing for

Descriptor and trap table cleanups. Add cleanly written accessors for IDT and GDT gates so the subarch may override them. Note that this allows the hypervisor to transparently tweak the DPL of the descriptors as well as the RPL of segments in those descriptors, with no unnecessary kernel code modification. It also allows the hypervisor implementation of the VMI to tweak the gates, allowing for

Big cleanup of LDT code. This code has very little type checking and is not frequently used, so I audited the code, added type checking and size optimizations to generate smaller assembly code. First, just introduce some small definitions that will be used later. Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.14-zach-work/arch/i386/kernel/entry.S

Big cleanup of LDT code. This code has very little type checking and is not frequently used, so I audited the code, added type checking and size optimizations to generate smaller assembly code. First, just introduce some small definitions that will be used later. Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.14-zach-work/arch/i386/kernel/entry.S

Add some convenient descriptor access functions and move them all into desc.h Patch-base: 2.6.13-rc5-mm1 Patch-keys: i386 desc cleanup Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/desc.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/desc.h 2005-08-09 19:43:38.000000000 -0700 +++

Add some convenient descriptor access functions and move them all into desc.h Patch-base: 2.6.13-rc5-mm1 Patch-keys: i386 desc cleanup Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/desc.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/desc.h 2005-08-09 19:43:38.000000000 -0700 +++