kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

x86-64: Convert exception stacks to per-cpu

Browse source 
Move the exception stacks to per-cpu, removing specific allocation code.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Brian Gerst 2009-01-19 00:38:58 +09:00 committed by Tejun Heo
parent 26f80bd6a9
commit 92d65b2371
1 changed files with 8 additions and 15 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

23
arch/x86/kernel/cpu/common.c
View file

@ -913,8 +913,9 @@ void __cpuinit pda_init(int cpu)
}
}
static char boot_exception_stacks[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ +
DEBUG_STKSZ] __page_aligned_bss;
static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks
[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ])
__aligned(PAGE_SIZE);
extern asmlinkage void ignore_sysret(void);
@ -972,15 +973,12 @@ void __cpuinit cpu_init(void)
struct tss_struct *t = &per_cpu(init_tss, cpu);
struct orig_ist *orig_ist = &per_cpu(orig_ist, cpu);
unsigned long v;
char *estacks = NULL;
struct task_struct *me;
int i;
/* CPU 0 is initialised in head64.c */
if (cpu != 0)
pda_init(cpu);
else
estacks = boot_exception_stacks;
me = current;
@ -1014,18 +1012,13 @@ void __cpuinit cpu_init(void)
* set up and load the per-CPU TSS
*/
if (!orig_ist->ist[0]) {
static const unsigned int order[N_EXCEPTION_STACKS] = {
[0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STACK_ORDER,
[DEBUG_STACK - 1] = DEBUG_STACK_ORDER
static const unsigned int sizes[N_EXCEPTION_STACKS] = {
[0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STKSZ,
[DEBUG_STACK - 1] = DEBUG_STKSZ
};
char *estacks = per_cpu(exception_stacks, cpu);
for (v = 0; v < N_EXCEPTION_STACKS; v++) {
if (cpu) {
estacks = (char *)__get_free_pages(GFP_ATOMIC, order[v]);
if (!estacks)
panic("Cannot allocate exception "
"stack %ld %d\n", v, cpu);
}
estacks += PAGE_SIZE << order[v];
estacks += sizes[v];
orig_ist->ist[v] = t->x86_tss.ist[v] =
(unsigned long)estacks;
}