uml: throw out CONFIG_MODE_TT
This patchset throws out tt mode, which has been non-functional for a while.
This is done in phases, interspersed with code cleanups on the affected files.
The removal is done as follows:
remove all code, config options, and files which depend on
CONFIG_MODE_TT
get rid of the CHOOSE_MODE macro, which decided whether to
call tt-mode or skas-mode code, and replace invocations with their
skas portions
replace all now-trivial procedures with their skas equivalents
There are now a bunch of now-redundant pieces of data structures, including
mode-specific pieces of the thread structure, pt_regs, and mm_context. These
are all replaced with their skas-specific contents.
As part of the ongoing style compliance project, I made a style pass over all
files that were changed. There are three such patches, one for each phase,
covering the files affected by that phase but no later ones.
I noticed that we weren't freeing the LDT state associated with a process when
it exited, so that's fixed in one of the later patches.
The last patch is a tidying patch which I've had for a while, but which caused
inexplicable crashes under tt mode. Since that is no longer a problem, this
can now go in.
This patch:
Start getting rid of tt mode support.
This patch throws out CONFIG_MODE_TT and all config options, code, and files
which depend on it.
CONFIG_MODE_SKAS is gone and everything that depends on it is included
unconditionally.
The few changed lines are in re-written Kconfig help, lines which needed
something skas-related removed from them, and a few more which weren't
strictly deletions.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index ecc458f..aa7b067 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -38,9 +38,7 @@
#include "choose-mode.h"
#include "mode_kern.h"
#include "mode.h"
-#ifdef UML_CONFIG_MODE_SKAS
#include "skas.h"
-#endif
#define DEFAULT_COMMAND_LINE "root=98:0"
@@ -132,43 +130,12 @@
/* Set in uml_ncpus_setup */
int ncpus = 1;
-#ifdef CONFIG_CMDLINE_ON_HOST
-/* Pointer set in linux_main, the array itself is private to each thread,
- * and changed at address space creation time so this poses no concurrency
- * problems.
- */
-static char *argv1_begin = NULL;
-static char *argv1_end = NULL;
-#endif
-
/* Set in early boot */
static int have_root __initdata = 0;
/* Set in uml_mem_setup and modified in linux_main */
long long physmem_size = 32 * 1024 * 1024;
-void set_cmdline(char *cmd)
-{
-#ifdef CONFIG_CMDLINE_ON_HOST
- char *umid, *ptr;
-
- if(CHOOSE_MODE(honeypot, 0)) return;
-
- umid = get_umid();
- if(*umid != '\0'){
- snprintf(argv1_begin,
- (argv1_end - argv1_begin) * sizeof(*ptr),
- "(%s) ", umid);
- ptr = &argv1_begin[strlen(argv1_begin)];
- }
- else ptr = argv1_begin;
-
- snprintf(ptr, (argv1_end - ptr) * sizeof(*ptr), "[%s]", cmd);
- memset(argv1_begin + strlen(argv1_begin), '\0',
- argv1_end - argv1_begin - strlen(argv1_begin));
-#endif
-}
-
static char *usage_string =
"User Mode Linux v%s\n"
" available at http://user-mode-linux.sourceforge.net/\n\n";
@@ -201,13 +168,10 @@
" root=/dev/ubd5\n\n"
);
-#ifndef CONFIG_MODE_TT
-
static int __init no_skas_debug_setup(char *line, int *add)
{
printf("'debug' is not necessary to gdb UML in skas mode - run \n");
- printf("'gdb linux' and disable CONFIG_CMDLINE_ON_HOST if gdb \n");
- printf("doesn't work as expected\n");
+ printf("'gdb linux'");
return 0;
}
@@ -217,8 +181,6 @@
" this flag is not needed to run gdb on UML in skas mode\n\n"
);
-#endif
-
#ifdef CONFIG_SMP
static int __init uml_ncpus_setup(char *line, int *add)
{
@@ -236,52 +198,6 @@
);
#endif
-static int force_tt = 0;
-
-#if defined(CONFIG_MODE_TT) && defined(CONFIG_MODE_SKAS)
-#define DEFAULT_TT 0
-
-static int __init mode_tt_setup(char *line, int *add)
-{
- force_tt = 1;
- return 0;
-}
-
-#else
-#ifdef CONFIG_MODE_SKAS
-
-#define DEFAULT_TT 0
-
-static int __init mode_tt_setup(char *line, int *add)
-{
- printf("CONFIG_MODE_TT disabled - 'mode=tt' ignored\n");
- return 0;
-}
-
-#else
-#ifdef CONFIG_MODE_TT
-
-#define DEFAULT_TT 1
-
-static int __init mode_tt_setup(char *line, int *add)
-{
- printf("CONFIG_MODE_SKAS disabled - 'mode=tt' redundant\n");
- return 0;
-}
-
-#endif
-#endif
-#endif
-
-__uml_setup("mode=tt", mode_tt_setup,
-"mode=tt\n"
-" When both CONFIG_MODE_TT and CONFIG_MODE_SKAS are enabled, this option\n"
-" forces UML to run in tt (tracing thread) mode. It is not the default\n"
-" because it's slower and less secure than skas mode.\n\n"
-);
-
-int mode_tt = DEFAULT_TT;
-
static int __init Usage(char *line, int *add)
{
const char **p;
@@ -357,29 +273,13 @@
add_arg(DEFAULT_COMMAND_LINE);
os_early_checks();
- if (force_tt)
- clear_can_do_skas();
- mode_tt = force_tt ? 1 : !can_do_skas();
-#ifndef CONFIG_MODE_TT
- if (mode_tt) {
- /*Since CONFIG_MODE_TT is #undef'ed, force_tt cannot be 1. So,
- * can_do_skas() returned 0, and the message is correct. */
- printf("Support for TT mode is disabled, and no SKAS support is present on the host.\n");
- exit(1);
- }
-#endif
-#ifndef CONFIG_MODE_SKAS
- mode = "TT";
-#else
- /* Show to the user the result of selection */
- if (mode_tt)
- mode = "TT";
- else if (proc_mm && ptrace_faultinfo)
+ can_do_skas();
+
+ if (proc_mm && ptrace_faultinfo)
mode = "SKAS3";
else
mode = "SKAS0";
-#endif
printf("UML running in %s mode\n", mode);
@@ -411,11 +311,6 @@
setup_machinename(init_utsname()->machine);
-#ifdef CONFIG_CMDLINE_ON_HOST
- argv1_begin = argv[1];
- argv1_end = &argv[1][strlen(argv[1])];
-#endif
-
highmem = 0;
iomem_size = (iomem_size + PAGE_SIZE - 1) & PAGE_MASK;
max_physmem = get_kmem_end() - uml_physmem - iomem_size - MIN_VMALLOC;