mirror of
https://github.com/brain-hackers/linux-brain.git
synced 2024-06-09 23:36:23 +09:00
0b4eb172cc
commit aec86b052df6541cc97c5fca44e5934cbea4963b upstream.
The entry flush mitigation can be enabled/disabled at runtime via a
debugfs file (entry_flush), which causes the kernel to patch itself to
enable/disable the relevant mitigations.
However depending on which mitigation we're using, it may not be safe to
do that patching while other CPUs are active. For example the following
crash:
sleeper[15639]: segfault (11) at c000000000004c20 nip c000000000004c20 lr c000000000004c20
Shows that we returned to userspace with a corrupted LR that points into
the kernel, due to executing the partially patched call to the fallback
entry flush (ie. we missed the LR restore).
Fix it by doing the patching under stop machine. The CPUs that aren't
doing the patching will be spinning in the core of the stop machine
logic. That is currently sufficient for our purposes, because none of
the patching we do is to that code or anywhere in the vicinity.
Fixes: f79643787e0a ("powerpc/64s: flush L1D on kernel entry")
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210506044959.1298123-2-mpe@ellerman.id.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
840 lines
24 KiB
C
840 lines
24 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org)
|
|
*
|
|
* Modifications for ppc64:
|
|
* Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com>
|
|
*
|
|
* Copyright 2008 Michael Ellerman, IBM Corporation.
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/jump_label.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/string.h>
|
|
#include <linux/init.h>
|
|
#include <linux/sched/mm.h>
|
|
#include <linux/stop_machine.h>
|
|
#include <asm/cputable.h>
|
|
#include <asm/code-patching.h>
|
|
#include <asm/page.h>
|
|
#include <asm/sections.h>
|
|
#include <asm/setup.h>
|
|
#include <asm/security_features.h>
|
|
#include <asm/firmware.h>
|
|
|
|
struct fixup_entry {
|
|
unsigned long mask;
|
|
unsigned long value;
|
|
long start_off;
|
|
long end_off;
|
|
long alt_start_off;
|
|
long alt_end_off;
|
|
};
|
|
|
|
static unsigned int *calc_addr(struct fixup_entry *fcur, long offset)
|
|
{
|
|
/*
|
|
* We store the offset to the code as a negative offset from
|
|
* the start of the alt_entry, to support the VDSO. This
|
|
* routine converts that back into an actual address.
|
|
*/
|
|
return (unsigned int *)((unsigned long)fcur + offset);
|
|
}
|
|
|
|
static int patch_alt_instruction(unsigned int *src, unsigned int *dest,
|
|
unsigned int *alt_start, unsigned int *alt_end)
|
|
{
|
|
unsigned int instr;
|
|
|
|
instr = *src;
|
|
|
|
if (instr_is_relative_branch(*src)) {
|
|
unsigned int *target = (unsigned int *)branch_target(src);
|
|
|
|
/* Branch within the section doesn't need translating */
|
|
if (target < alt_start || target > alt_end) {
|
|
instr = translate_branch(dest, src);
|
|
if (!instr)
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
raw_patch_instruction(dest, instr);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int patch_feature_section(unsigned long value, struct fixup_entry *fcur)
|
|
{
|
|
unsigned int *start, *end, *alt_start, *alt_end, *src, *dest;
|
|
|
|
start = calc_addr(fcur, fcur->start_off);
|
|
end = calc_addr(fcur, fcur->end_off);
|
|
alt_start = calc_addr(fcur, fcur->alt_start_off);
|
|
alt_end = calc_addr(fcur, fcur->alt_end_off);
|
|
|
|
if ((alt_end - alt_start) > (end - start))
|
|
return 1;
|
|
|
|
if ((value & fcur->mask) == fcur->value)
|
|
return 0;
|
|
|
|
src = alt_start;
|
|
dest = start;
|
|
|
|
for (; src < alt_end; src++, dest++) {
|
|
if (patch_alt_instruction(src, dest, alt_start, alt_end))
|
|
return 1;
|
|
}
|
|
|
|
for (; dest < end; dest++)
|
|
raw_patch_instruction(dest, PPC_INST_NOP);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void do_feature_fixups(unsigned long value, void *fixup_start, void *fixup_end)
|
|
{
|
|
struct fixup_entry *fcur, *fend;
|
|
|
|
fcur = fixup_start;
|
|
fend = fixup_end;
|
|
|
|
for (; fcur < fend; fcur++) {
|
|
if (patch_feature_section(value, fcur)) {
|
|
WARN_ON(1);
|
|
printk("Unable to patch feature section at %p - %p" \
|
|
" with %p - %p\n",
|
|
calc_addr(fcur, fcur->start_off),
|
|
calc_addr(fcur, fcur->end_off),
|
|
calc_addr(fcur, fcur->alt_start_off),
|
|
calc_addr(fcur, fcur->alt_end_off));
|
|
}
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_PPC_BOOK3S_64
|
|
static void do_stf_entry_barrier_fixups(enum stf_barrier_type types)
|
|
{
|
|
unsigned int instrs[3], *dest;
|
|
long *start, *end;
|
|
int i;
|
|
|
|
start = PTRRELOC(&__start___stf_entry_barrier_fixup),
|
|
end = PTRRELOC(&__stop___stf_entry_barrier_fixup);
|
|
|
|
instrs[0] = 0x60000000; /* nop */
|
|
instrs[1] = 0x60000000; /* nop */
|
|
instrs[2] = 0x60000000; /* nop */
|
|
|
|
i = 0;
|
|
if (types & STF_BARRIER_FALLBACK) {
|
|
instrs[i++] = 0x7d4802a6; /* mflr r10 */
|
|
instrs[i++] = 0x60000000; /* branch patched below */
|
|
instrs[i++] = 0x7d4803a6; /* mtlr r10 */
|
|
} else if (types & STF_BARRIER_EIEIO) {
|
|
instrs[i++] = 0x7e0006ac; /* eieio + bit 6 hint */
|
|
} else if (types & STF_BARRIER_SYNC_ORI) {
|
|
instrs[i++] = 0x7c0004ac; /* hwsync */
|
|
instrs[i++] = 0xe94d0000; /* ld r10,0(r13) */
|
|
instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
|
|
}
|
|
|
|
for (i = 0; start < end; start++, i++) {
|
|
dest = (void *)start + *start;
|
|
|
|
pr_devel("patching dest %lx\n", (unsigned long)dest);
|
|
|
|
patch_instruction(dest, instrs[0]);
|
|
|
|
if (types & STF_BARRIER_FALLBACK)
|
|
patch_branch(dest + 1, (unsigned long)&stf_barrier_fallback,
|
|
BRANCH_SET_LINK);
|
|
else
|
|
patch_instruction(dest + 1, instrs[1]);
|
|
|
|
patch_instruction(dest + 2, instrs[2]);
|
|
}
|
|
|
|
printk(KERN_DEBUG "stf-barrier: patched %d entry locations (%s barrier)\n", i,
|
|
(types == STF_BARRIER_NONE) ? "no" :
|
|
(types == STF_BARRIER_FALLBACK) ? "fallback" :
|
|
(types == STF_BARRIER_EIEIO) ? "eieio" :
|
|
(types == (STF_BARRIER_SYNC_ORI)) ? "hwsync"
|
|
: "unknown");
|
|
}
|
|
|
|
static void do_stf_exit_barrier_fixups(enum stf_barrier_type types)
|
|
{
|
|
unsigned int instrs[6], *dest;
|
|
long *start, *end;
|
|
int i;
|
|
|
|
start = PTRRELOC(&__start___stf_exit_barrier_fixup),
|
|
end = PTRRELOC(&__stop___stf_exit_barrier_fixup);
|
|
|
|
instrs[0] = 0x60000000; /* nop */
|
|
instrs[1] = 0x60000000; /* nop */
|
|
instrs[2] = 0x60000000; /* nop */
|
|
instrs[3] = 0x60000000; /* nop */
|
|
instrs[4] = 0x60000000; /* nop */
|
|
instrs[5] = 0x60000000; /* nop */
|
|
|
|
i = 0;
|
|
if (types & STF_BARRIER_FALLBACK || types & STF_BARRIER_SYNC_ORI) {
|
|
if (cpu_has_feature(CPU_FTR_HVMODE)) {
|
|
instrs[i++] = 0x7db14ba6; /* mtspr 0x131, r13 (HSPRG1) */
|
|
instrs[i++] = 0x7db04aa6; /* mfspr r13, 0x130 (HSPRG0) */
|
|
} else {
|
|
instrs[i++] = 0x7db243a6; /* mtsprg 2,r13 */
|
|
instrs[i++] = 0x7db142a6; /* mfsprg r13,1 */
|
|
}
|
|
instrs[i++] = 0x7c0004ac; /* hwsync */
|
|
instrs[i++] = 0xe9ad0000; /* ld r13,0(r13) */
|
|
instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
|
|
if (cpu_has_feature(CPU_FTR_HVMODE)) {
|
|
instrs[i++] = 0x7db14aa6; /* mfspr r13, 0x131 (HSPRG1) */
|
|
} else {
|
|
instrs[i++] = 0x7db242a6; /* mfsprg r13,2 */
|
|
}
|
|
} else if (types & STF_BARRIER_EIEIO) {
|
|
instrs[i++] = 0x7e0006ac; /* eieio + bit 6 hint */
|
|
}
|
|
|
|
for (i = 0; start < end; start++, i++) {
|
|
dest = (void *)start + *start;
|
|
|
|
pr_devel("patching dest %lx\n", (unsigned long)dest);
|
|
|
|
patch_instruction(dest, instrs[0]);
|
|
patch_instruction(dest + 1, instrs[1]);
|
|
patch_instruction(dest + 2, instrs[2]);
|
|
patch_instruction(dest + 3, instrs[3]);
|
|
patch_instruction(dest + 4, instrs[4]);
|
|
patch_instruction(dest + 5, instrs[5]);
|
|
}
|
|
printk(KERN_DEBUG "stf-barrier: patched %d exit locations (%s barrier)\n", i,
|
|
(types == STF_BARRIER_NONE) ? "no" :
|
|
(types == STF_BARRIER_FALLBACK) ? "fallback" :
|
|
(types == STF_BARRIER_EIEIO) ? "eieio" :
|
|
(types == (STF_BARRIER_SYNC_ORI)) ? "hwsync"
|
|
: "unknown");
|
|
}
|
|
|
|
static int __do_stf_barrier_fixups(void *data)
|
|
{
|
|
enum stf_barrier_type *types = data;
|
|
|
|
do_stf_entry_barrier_fixups(*types);
|
|
do_stf_exit_barrier_fixups(*types);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void do_stf_barrier_fixups(enum stf_barrier_type types)
|
|
{
|
|
/*
|
|
* The call to the fallback entry flush, and the fallback/sync-ori exit
|
|
* flush can not be safely patched in/out while other CPUs are executing
|
|
* them. So call __do_stf_barrier_fixups() on one CPU while all other CPUs
|
|
* spin in the stop machine core with interrupts hard disabled.
|
|
*/
|
|
stop_machine(__do_stf_barrier_fixups, &types, NULL);
|
|
}
|
|
|
|
void do_uaccess_flush_fixups(enum l1d_flush_type types)
|
|
{
|
|
unsigned int instrs[4], *dest;
|
|
long *start, *end;
|
|
int i;
|
|
|
|
start = PTRRELOC(&__start___uaccess_flush_fixup);
|
|
end = PTRRELOC(&__stop___uaccess_flush_fixup);
|
|
|
|
instrs[0] = 0x60000000; /* nop */
|
|
instrs[1] = 0x60000000; /* nop */
|
|
instrs[2] = 0x60000000; /* nop */
|
|
instrs[3] = 0x4e800020; /* blr */
|
|
|
|
i = 0;
|
|
if (types == L1D_FLUSH_FALLBACK) {
|
|
instrs[3] = 0x60000000; /* nop */
|
|
/* fallthrough to fallback flush */
|
|
}
|
|
|
|
if (types & L1D_FLUSH_ORI) {
|
|
instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
|
|
instrs[i++] = 0x63de0000; /* ori 30,30,0 L1d flush*/
|
|
}
|
|
|
|
if (types & L1D_FLUSH_MTTRIG)
|
|
instrs[i++] = 0x7c12dba6; /* mtspr TRIG2,r0 (SPR #882) */
|
|
|
|
for (i = 0; start < end; start++, i++) {
|
|
dest = (void *)start + *start;
|
|
|
|
pr_devel("patching dest %lx\n", (unsigned long)dest);
|
|
|
|
patch_instruction(dest, instrs[0]);
|
|
|
|
patch_instruction((dest + 1), instrs[1]);
|
|
patch_instruction((dest + 2), instrs[2]);
|
|
patch_instruction((dest + 3), instrs[3]);
|
|
}
|
|
|
|
printk(KERN_DEBUG "uaccess-flush: patched %d locations (%s flush)\n", i,
|
|
(types == L1D_FLUSH_NONE) ? "no" :
|
|
(types == L1D_FLUSH_FALLBACK) ? "fallback displacement" :
|
|
(types & L1D_FLUSH_ORI) ? (types & L1D_FLUSH_MTTRIG)
|
|
? "ori+mttrig type"
|
|
: "ori type" :
|
|
(types & L1D_FLUSH_MTTRIG) ? "mttrig type"
|
|
: "unknown");
|
|
}
|
|
|
|
static int __do_entry_flush_fixups(void *data)
|
|
{
|
|
enum l1d_flush_type types = *(enum l1d_flush_type *)data;
|
|
unsigned int instrs[3], *dest;
|
|
long *start, *end;
|
|
int i;
|
|
|
|
start = PTRRELOC(&__start___entry_flush_fixup);
|
|
end = PTRRELOC(&__stop___entry_flush_fixup);
|
|
|
|
instrs[0] = 0x60000000; /* nop */
|
|
instrs[1] = 0x60000000; /* nop */
|
|
instrs[2] = 0x60000000; /* nop */
|
|
|
|
i = 0;
|
|
if (types == L1D_FLUSH_FALLBACK) {
|
|
instrs[i++] = 0x7d4802a6; /* mflr r10 */
|
|
instrs[i++] = 0x60000000; /* branch patched below */
|
|
instrs[i++] = 0x7d4803a6; /* mtlr r10 */
|
|
}
|
|
|
|
if (types & L1D_FLUSH_ORI) {
|
|
instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
|
|
instrs[i++] = 0x63de0000; /* ori 30,30,0 L1d flush*/
|
|
}
|
|
|
|
if (types & L1D_FLUSH_MTTRIG)
|
|
instrs[i++] = 0x7c12dba6; /* mtspr TRIG2,r0 (SPR #882) */
|
|
|
|
for (i = 0; start < end; start++, i++) {
|
|
dest = (void *)start + *start;
|
|
|
|
pr_devel("patching dest %lx\n", (unsigned long)dest);
|
|
|
|
patch_instruction(dest, instrs[0]);
|
|
|
|
if (types == L1D_FLUSH_FALLBACK)
|
|
patch_branch((dest + 1), (unsigned long)&entry_flush_fallback,
|
|
BRANCH_SET_LINK);
|
|
else
|
|
patch_instruction((dest + 1), instrs[1]);
|
|
|
|
patch_instruction((dest + 2), instrs[2]);
|
|
}
|
|
|
|
printk(KERN_DEBUG "entry-flush: patched %d locations (%s flush)\n", i,
|
|
(types == L1D_FLUSH_NONE) ? "no" :
|
|
(types == L1D_FLUSH_FALLBACK) ? "fallback displacement" :
|
|
(types & L1D_FLUSH_ORI) ? (types & L1D_FLUSH_MTTRIG)
|
|
? "ori+mttrig type"
|
|
: "ori type" :
|
|
(types & L1D_FLUSH_MTTRIG) ? "mttrig type"
|
|
: "unknown");
|
|
|
|
return 0;
|
|
}
|
|
|
|
void do_entry_flush_fixups(enum l1d_flush_type types)
|
|
{
|
|
/*
|
|
* The call to the fallback flush can not be safely patched in/out while
|
|
* other CPUs are executing it. So call __do_entry_flush_fixups() on one
|
|
* CPU while all other CPUs spin in the stop machine core with interrupts
|
|
* hard disabled.
|
|
*/
|
|
stop_machine(__do_entry_flush_fixups, &types, NULL);
|
|
}
|
|
|
|
void do_rfi_flush_fixups(enum l1d_flush_type types)
|
|
{
|
|
unsigned int instrs[3], *dest;
|
|
long *start, *end;
|
|
int i;
|
|
|
|
start = PTRRELOC(&__start___rfi_flush_fixup),
|
|
end = PTRRELOC(&__stop___rfi_flush_fixup);
|
|
|
|
instrs[0] = 0x60000000; /* nop */
|
|
instrs[1] = 0x60000000; /* nop */
|
|
instrs[2] = 0x60000000; /* nop */
|
|
|
|
if (types & L1D_FLUSH_FALLBACK)
|
|
/* b .+16 to fallback flush */
|
|
instrs[0] = 0x48000010;
|
|
|
|
i = 0;
|
|
if (types & L1D_FLUSH_ORI) {
|
|
instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
|
|
instrs[i++] = 0x63de0000; /* ori 30,30,0 L1d flush*/
|
|
}
|
|
|
|
if (types & L1D_FLUSH_MTTRIG)
|
|
instrs[i++] = 0x7c12dba6; /* mtspr TRIG2,r0 (SPR #882) */
|
|
|
|
for (i = 0; start < end; start++, i++) {
|
|
dest = (void *)start + *start;
|
|
|
|
pr_devel("patching dest %lx\n", (unsigned long)dest);
|
|
|
|
patch_instruction(dest, instrs[0]);
|
|
patch_instruction(dest + 1, instrs[1]);
|
|
patch_instruction(dest + 2, instrs[2]);
|
|
}
|
|
|
|
printk(KERN_DEBUG "rfi-flush: patched %d locations (%s flush)\n", i,
|
|
(types == L1D_FLUSH_NONE) ? "no" :
|
|
(types == L1D_FLUSH_FALLBACK) ? "fallback displacement" :
|
|
(types & L1D_FLUSH_ORI) ? (types & L1D_FLUSH_MTTRIG)
|
|
? "ori+mttrig type"
|
|
: "ori type" :
|
|
(types & L1D_FLUSH_MTTRIG) ? "mttrig type"
|
|
: "unknown");
|
|
}
|
|
|
|
void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end)
|
|
{
|
|
unsigned int instr, *dest;
|
|
long *start, *end;
|
|
int i;
|
|
|
|
start = fixup_start;
|
|
end = fixup_end;
|
|
|
|
instr = 0x60000000; /* nop */
|
|
|
|
if (enable) {
|
|
pr_info("barrier-nospec: using ORI speculation barrier\n");
|
|
instr = 0x63ff0000; /* ori 31,31,0 speculation barrier */
|
|
}
|
|
|
|
for (i = 0; start < end; start++, i++) {
|
|
dest = (void *)start + *start;
|
|
|
|
pr_devel("patching dest %lx\n", (unsigned long)dest);
|
|
patch_instruction(dest, instr);
|
|
}
|
|
|
|
printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i);
|
|
}
|
|
|
|
#endif /* CONFIG_PPC_BOOK3S_64 */
|
|
|
|
#ifdef CONFIG_PPC_BARRIER_NOSPEC
|
|
void do_barrier_nospec_fixups(bool enable)
|
|
{
|
|
void *start, *end;
|
|
|
|
start = PTRRELOC(&__start___barrier_nospec_fixup),
|
|
end = PTRRELOC(&__stop___barrier_nospec_fixup);
|
|
|
|
do_barrier_nospec_fixups_range(enable, start, end);
|
|
}
|
|
#endif /* CONFIG_PPC_BARRIER_NOSPEC */
|
|
|
|
#ifdef CONFIG_PPC_FSL_BOOK3E
|
|
void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end)
|
|
{
|
|
unsigned int instr[2], *dest;
|
|
long *start, *end;
|
|
int i;
|
|
|
|
start = fixup_start;
|
|
end = fixup_end;
|
|
|
|
instr[0] = PPC_INST_NOP;
|
|
instr[1] = PPC_INST_NOP;
|
|
|
|
if (enable) {
|
|
pr_info("barrier-nospec: using isync; sync as speculation barrier\n");
|
|
instr[0] = PPC_INST_ISYNC;
|
|
instr[1] = PPC_INST_SYNC;
|
|
}
|
|
|
|
for (i = 0; start < end; start++, i++) {
|
|
dest = (void *)start + *start;
|
|
|
|
pr_devel("patching dest %lx\n", (unsigned long)dest);
|
|
patch_instruction(dest, instr[0]);
|
|
patch_instruction(dest + 1, instr[1]);
|
|
}
|
|
|
|
printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i);
|
|
}
|
|
|
|
static void patch_btb_flush_section(long *curr)
|
|
{
|
|
unsigned int *start, *end;
|
|
|
|
start = (void *)curr + *curr;
|
|
end = (void *)curr + *(curr + 1);
|
|
for (; start < end; start++) {
|
|
pr_devel("patching dest %lx\n", (unsigned long)start);
|
|
patch_instruction(start, PPC_INST_NOP);
|
|
}
|
|
}
|
|
|
|
void do_btb_flush_fixups(void)
|
|
{
|
|
long *start, *end;
|
|
|
|
start = PTRRELOC(&__start__btb_flush_fixup);
|
|
end = PTRRELOC(&__stop__btb_flush_fixup);
|
|
|
|
for (; start < end; start += 2)
|
|
patch_btb_flush_section(start);
|
|
}
|
|
#endif /* CONFIG_PPC_FSL_BOOK3E */
|
|
|
|
void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end)
|
|
{
|
|
long *start, *end;
|
|
unsigned int *dest;
|
|
|
|
if (!(value & CPU_FTR_LWSYNC))
|
|
return ;
|
|
|
|
start = fixup_start;
|
|
end = fixup_end;
|
|
|
|
for (; start < end; start++) {
|
|
dest = (void *)start + *start;
|
|
raw_patch_instruction(dest, PPC_INST_LWSYNC);
|
|
}
|
|
}
|
|
|
|
static void do_final_fixups(void)
|
|
{
|
|
#if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE)
|
|
int *src, *dest;
|
|
unsigned long length;
|
|
|
|
if (PHYSICAL_START == 0)
|
|
return;
|
|
|
|
src = (int *)(KERNELBASE + PHYSICAL_START);
|
|
dest = (int *)KERNELBASE;
|
|
length = (__end_interrupts - _stext) / sizeof(int);
|
|
|
|
while (length--) {
|
|
raw_patch_instruction(dest, *src);
|
|
src++;
|
|
dest++;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
static unsigned long __initdata saved_cpu_features;
|
|
static unsigned int __initdata saved_mmu_features;
|
|
#ifdef CONFIG_PPC64
|
|
static unsigned long __initdata saved_firmware_features;
|
|
#endif
|
|
|
|
void __init apply_feature_fixups(void)
|
|
{
|
|
struct cpu_spec *spec = PTRRELOC(*PTRRELOC(&cur_cpu_spec));
|
|
|
|
*PTRRELOC(&saved_cpu_features) = spec->cpu_features;
|
|
*PTRRELOC(&saved_mmu_features) = spec->mmu_features;
|
|
|
|
/*
|
|
* Apply the CPU-specific and firmware specific fixups to kernel text
|
|
* (nop out sections not relevant to this CPU or this firmware).
|
|
*/
|
|
do_feature_fixups(spec->cpu_features,
|
|
PTRRELOC(&__start___ftr_fixup),
|
|
PTRRELOC(&__stop___ftr_fixup));
|
|
|
|
do_feature_fixups(spec->mmu_features,
|
|
PTRRELOC(&__start___mmu_ftr_fixup),
|
|
PTRRELOC(&__stop___mmu_ftr_fixup));
|
|
|
|
do_lwsync_fixups(spec->cpu_features,
|
|
PTRRELOC(&__start___lwsync_fixup),
|
|
PTRRELOC(&__stop___lwsync_fixup));
|
|
|
|
#ifdef CONFIG_PPC64
|
|
saved_firmware_features = powerpc_firmware_features;
|
|
do_feature_fixups(powerpc_firmware_features,
|
|
&__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
|
|
#endif
|
|
do_final_fixups();
|
|
}
|
|
|
|
void __init setup_feature_keys(void)
|
|
{
|
|
/*
|
|
* Initialise jump label. This causes all the cpu/mmu_has_feature()
|
|
* checks to take on their correct polarity based on the current set of
|
|
* CPU/MMU features.
|
|
*/
|
|
jump_label_init();
|
|
cpu_feature_keys_init();
|
|
mmu_feature_keys_init();
|
|
}
|
|
|
|
static int __init check_features(void)
|
|
{
|
|
WARN(saved_cpu_features != cur_cpu_spec->cpu_features,
|
|
"CPU features changed after feature patching!\n");
|
|
WARN(saved_mmu_features != cur_cpu_spec->mmu_features,
|
|
"MMU features changed after feature patching!\n");
|
|
#ifdef CONFIG_PPC64
|
|
WARN(saved_firmware_features != powerpc_firmware_features,
|
|
"Firmware features changed after feature patching!\n");
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
late_initcall(check_features);
|
|
|
|
#ifdef CONFIG_FTR_FIXUP_SELFTEST
|
|
|
|
#define check(x) \
|
|
if (!(x)) printk("feature-fixups: test failed at line %d\n", __LINE__);
|
|
|
|
/* This must be after the text it fixes up, vmlinux.lds.S enforces that atm */
|
|
static struct fixup_entry fixup;
|
|
|
|
static long calc_offset(struct fixup_entry *entry, unsigned int *p)
|
|
{
|
|
return (unsigned long)p - (unsigned long)entry;
|
|
}
|
|
|
|
static void test_basic_patching(void)
|
|
{
|
|
extern unsigned int ftr_fixup_test1[];
|
|
extern unsigned int end_ftr_fixup_test1[];
|
|
extern unsigned int ftr_fixup_test1_orig[];
|
|
extern unsigned int ftr_fixup_test1_expected[];
|
|
int size = 4 * (end_ftr_fixup_test1 - ftr_fixup_test1);
|
|
|
|
fixup.value = fixup.mask = 8;
|
|
fixup.start_off = calc_offset(&fixup, ftr_fixup_test1 + 1);
|
|
fixup.end_off = calc_offset(&fixup, ftr_fixup_test1 + 2);
|
|
fixup.alt_start_off = fixup.alt_end_off = 0;
|
|
|
|
/* Sanity check */
|
|
check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
|
|
|
|
/* Check we don't patch if the value matches */
|
|
patch_feature_section(8, &fixup);
|
|
check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
|
|
|
|
/* Check we do patch if the value doesn't match */
|
|
patch_feature_section(0, &fixup);
|
|
check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0);
|
|
|
|
/* Check we do patch if the mask doesn't match */
|
|
memcpy(ftr_fixup_test1, ftr_fixup_test1_orig, size);
|
|
check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
|
|
patch_feature_section(~8, &fixup);
|
|
check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0);
|
|
}
|
|
|
|
static void test_alternative_patching(void)
|
|
{
|
|
extern unsigned int ftr_fixup_test2[];
|
|
extern unsigned int end_ftr_fixup_test2[];
|
|
extern unsigned int ftr_fixup_test2_orig[];
|
|
extern unsigned int ftr_fixup_test2_alt[];
|
|
extern unsigned int ftr_fixup_test2_expected[];
|
|
int size = 4 * (end_ftr_fixup_test2 - ftr_fixup_test2);
|
|
|
|
fixup.value = fixup.mask = 0xF;
|
|
fixup.start_off = calc_offset(&fixup, ftr_fixup_test2 + 1);
|
|
fixup.end_off = calc_offset(&fixup, ftr_fixup_test2 + 2);
|
|
fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test2_alt);
|
|
fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test2_alt + 1);
|
|
|
|
/* Sanity check */
|
|
check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
|
|
|
|
/* Check we don't patch if the value matches */
|
|
patch_feature_section(0xF, &fixup);
|
|
check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
|
|
|
|
/* Check we do patch if the value doesn't match */
|
|
patch_feature_section(0, &fixup);
|
|
check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0);
|
|
|
|
/* Check we do patch if the mask doesn't match */
|
|
memcpy(ftr_fixup_test2, ftr_fixup_test2_orig, size);
|
|
check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
|
|
patch_feature_section(~0xF, &fixup);
|
|
check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0);
|
|
}
|
|
|
|
static void test_alternative_case_too_big(void)
|
|
{
|
|
extern unsigned int ftr_fixup_test3[];
|
|
extern unsigned int end_ftr_fixup_test3[];
|
|
extern unsigned int ftr_fixup_test3_orig[];
|
|
extern unsigned int ftr_fixup_test3_alt[];
|
|
int size = 4 * (end_ftr_fixup_test3 - ftr_fixup_test3);
|
|
|
|
fixup.value = fixup.mask = 0xC;
|
|
fixup.start_off = calc_offset(&fixup, ftr_fixup_test3 + 1);
|
|
fixup.end_off = calc_offset(&fixup, ftr_fixup_test3 + 2);
|
|
fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test3_alt);
|
|
fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test3_alt + 2);
|
|
|
|
/* Sanity check */
|
|
check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
|
|
|
|
/* Expect nothing to be patched, and the error returned to us */
|
|
check(patch_feature_section(0xF, &fixup) == 1);
|
|
check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
|
|
check(patch_feature_section(0, &fixup) == 1);
|
|
check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
|
|
check(patch_feature_section(~0xF, &fixup) == 1);
|
|
check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
|
|
}
|
|
|
|
static void test_alternative_case_too_small(void)
|
|
{
|
|
extern unsigned int ftr_fixup_test4[];
|
|
extern unsigned int end_ftr_fixup_test4[];
|
|
extern unsigned int ftr_fixup_test4_orig[];
|
|
extern unsigned int ftr_fixup_test4_alt[];
|
|
extern unsigned int ftr_fixup_test4_expected[];
|
|
int size = 4 * (end_ftr_fixup_test4 - ftr_fixup_test4);
|
|
unsigned long flag;
|
|
|
|
/* Check a high-bit flag */
|
|
flag = 1UL << ((sizeof(unsigned long) - 1) * 8);
|
|
fixup.value = fixup.mask = flag;
|
|
fixup.start_off = calc_offset(&fixup, ftr_fixup_test4 + 1);
|
|
fixup.end_off = calc_offset(&fixup, ftr_fixup_test4 + 5);
|
|
fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test4_alt);
|
|
fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test4_alt + 2);
|
|
|
|
/* Sanity check */
|
|
check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
|
|
|
|
/* Check we don't patch if the value matches */
|
|
patch_feature_section(flag, &fixup);
|
|
check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
|
|
|
|
/* Check we do patch if the value doesn't match */
|
|
patch_feature_section(0, &fixup);
|
|
check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0);
|
|
|
|
/* Check we do patch if the mask doesn't match */
|
|
memcpy(ftr_fixup_test4, ftr_fixup_test4_orig, size);
|
|
check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
|
|
patch_feature_section(~flag, &fixup);
|
|
check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0);
|
|
}
|
|
|
|
static void test_alternative_case_with_branch(void)
|
|
{
|
|
extern unsigned int ftr_fixup_test5[];
|
|
extern unsigned int end_ftr_fixup_test5[];
|
|
extern unsigned int ftr_fixup_test5_expected[];
|
|
int size = 4 * (end_ftr_fixup_test5 - ftr_fixup_test5);
|
|
|
|
check(memcmp(ftr_fixup_test5, ftr_fixup_test5_expected, size) == 0);
|
|
}
|
|
|
|
static void test_alternative_case_with_external_branch(void)
|
|
{
|
|
extern unsigned int ftr_fixup_test6[];
|
|
extern unsigned int end_ftr_fixup_test6[];
|
|
extern unsigned int ftr_fixup_test6_expected[];
|
|
int size = 4 * (end_ftr_fixup_test6 - ftr_fixup_test6);
|
|
|
|
check(memcmp(ftr_fixup_test6, ftr_fixup_test6_expected, size) == 0);
|
|
}
|
|
|
|
static void test_alternative_case_with_branch_to_end(void)
|
|
{
|
|
extern unsigned int ftr_fixup_test7[];
|
|
extern unsigned int end_ftr_fixup_test7[];
|
|
extern unsigned int ftr_fixup_test7_expected[];
|
|
int size = 4 * (end_ftr_fixup_test7 - ftr_fixup_test7);
|
|
|
|
check(memcmp(ftr_fixup_test7, ftr_fixup_test7_expected, size) == 0);
|
|
}
|
|
|
|
static void test_cpu_macros(void)
|
|
{
|
|
extern u8 ftr_fixup_test_FTR_macros[];
|
|
extern u8 ftr_fixup_test_FTR_macros_expected[];
|
|
unsigned long size = ftr_fixup_test_FTR_macros_expected -
|
|
ftr_fixup_test_FTR_macros;
|
|
|
|
/* The fixups have already been done for us during boot */
|
|
check(memcmp(ftr_fixup_test_FTR_macros,
|
|
ftr_fixup_test_FTR_macros_expected, size) == 0);
|
|
}
|
|
|
|
static void test_fw_macros(void)
|
|
{
|
|
#ifdef CONFIG_PPC64
|
|
extern u8 ftr_fixup_test_FW_FTR_macros[];
|
|
extern u8 ftr_fixup_test_FW_FTR_macros_expected[];
|
|
unsigned long size = ftr_fixup_test_FW_FTR_macros_expected -
|
|
ftr_fixup_test_FW_FTR_macros;
|
|
|
|
/* The fixups have already been done for us during boot */
|
|
check(memcmp(ftr_fixup_test_FW_FTR_macros,
|
|
ftr_fixup_test_FW_FTR_macros_expected, size) == 0);
|
|
#endif
|
|
}
|
|
|
|
static void test_lwsync_macros(void)
|
|
{
|
|
extern u8 lwsync_fixup_test[];
|
|
extern u8 end_lwsync_fixup_test[];
|
|
extern u8 lwsync_fixup_test_expected_LWSYNC[];
|
|
extern u8 lwsync_fixup_test_expected_SYNC[];
|
|
unsigned long size = end_lwsync_fixup_test -
|
|
lwsync_fixup_test;
|
|
|
|
/* The fixups have already been done for us during boot */
|
|
if (cur_cpu_spec->cpu_features & CPU_FTR_LWSYNC) {
|
|
check(memcmp(lwsync_fixup_test,
|
|
lwsync_fixup_test_expected_LWSYNC, size) == 0);
|
|
} else {
|
|
check(memcmp(lwsync_fixup_test,
|
|
lwsync_fixup_test_expected_SYNC, size) == 0);
|
|
}
|
|
}
|
|
|
|
static int __init test_feature_fixups(void)
|
|
{
|
|
printk(KERN_DEBUG "Running feature fixup self-tests ...\n");
|
|
|
|
test_basic_patching();
|
|
test_alternative_patching();
|
|
test_alternative_case_too_big();
|
|
test_alternative_case_too_small();
|
|
test_alternative_case_with_branch();
|
|
test_alternative_case_with_external_branch();
|
|
test_alternative_case_with_branch_to_end();
|
|
test_cpu_macros();
|
|
test_fw_macros();
|
|
test_lwsync_macros();
|
|
|
|
return 0;
|
|
}
|
|
late_initcall(test_feature_fixups);
|
|
|
|
#endif /* CONFIG_FTR_FIXUP_SELFTEST */
|