linux/arch/powerpc/lib/feature-fixups.c
Nicholas Piggin 9a32a7e78b powerpc/64s: flush L1D after user accesses
IBM Power9 processors can speculatively operate on data in the L1 cache
before it has been completely validated, via a way-prediction mechanism. It
is not possible for an attacker to determine the contents of impermissible
memory using this method, since these systems implement a combination of
hardware and software security measures to prevent scenarios where
protected data could be leaked.

However these measures don't address the scenario where an attacker induces
the operating system to speculatively execute instructions using data that
the attacker controls. This can be used for example to speculatively bypass
"kernel user access prevention" techniques, as discovered by Anthony
Steinhauser of Google's Safeside Project. This is not an attack by itself,
but there is a possibility it could be used in conjunction with
side-channels or other weaknesses in the privileged code to construct an
attack.

This issue can be mitigated by flushing the L1 cache between privilege
boundaries of concern. This patch flushes the L1 cache after user accesses.

This is part of the fix for CVE-2020-4788.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2020-11-19 23:47:18 +11:00

892 lines
27 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 <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>
#include <asm/inst.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 struct ppc_inst *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 (struct ppc_inst *)((unsigned long)fcur + offset);
}
static int patch_alt_instruction(struct ppc_inst *src, struct ppc_inst *dest,
struct ppc_inst *alt_start, struct ppc_inst *alt_end)
{
int err;
struct ppc_inst instr;
instr = ppc_inst_read(src);
if (instr_is_relative_branch(*src)) {
struct ppc_inst *target = (struct ppc_inst *)branch_target(src);
/* Branch within the section doesn't need translating */
if (target < alt_start || target > alt_end) {
err = translate_branch(&instr, dest, src);
if (err)
return 1;
}
}
raw_patch_instruction(dest, instr);
return 0;
}
static int patch_feature_section(unsigned long value, struct fixup_entry *fcur)
{
struct ppc_inst *start, *end, *alt_start, *alt_end, *src, *dest, nop;
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 = ppc_inst_next(src, src),
dest = ppc_inst_next(dest, dest)) {
if (patch_alt_instruction(src, dest, alt_start, alt_end))
return 1;
}
nop = ppc_inst(PPC_INST_NOP);
for (; dest < end; dest = ppc_inst_next(dest, &nop))
raw_patch_instruction(dest, 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((struct ppc_inst *)dest, ppc_inst(instrs[0]));
if (types & STF_BARRIER_FALLBACK)
patch_branch((struct ppc_inst *)(dest + 1),
(unsigned long)&stf_barrier_fallback,
BRANCH_SET_LINK);
else
patch_instruction((struct ppc_inst *)(dest + 1),
ppc_inst(instrs[1]));
patch_instruction((struct ppc_inst *)(dest + 2), ppc_inst(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((struct ppc_inst *)dest, ppc_inst(instrs[0]));
patch_instruction((struct ppc_inst *)(dest + 1), ppc_inst(instrs[1]));
patch_instruction((struct ppc_inst *)(dest + 2), ppc_inst(instrs[2]));
patch_instruction((struct ppc_inst *)(dest + 3), ppc_inst(instrs[3]));
patch_instruction((struct ppc_inst *)(dest + 4), ppc_inst(instrs[4]));
patch_instruction((struct ppc_inst *)(dest + 5), ppc_inst(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");
}
void do_stf_barrier_fixups(enum stf_barrier_type types)
{
do_stf_entry_barrier_fixups(types);
do_stf_exit_barrier_fixups(types);
}
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((struct ppc_inst *)dest, ppc_inst(instrs[0]));
patch_instruction((struct ppc_inst *)(dest + 1), ppc_inst(instrs[1]));
patch_instruction((struct ppc_inst *)(dest + 2), ppc_inst(instrs[2]));
patch_instruction((struct ppc_inst *)(dest + 3), ppc_inst(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");
}
void do_entry_flush_fixups(enum l1d_flush_type types)
{
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((struct ppc_inst *)dest, ppc_inst(instrs[0]));
if (types == L1D_FLUSH_FALLBACK)
patch_branch((struct ppc_inst *)(dest + 1), (unsigned long)&entry_flush_fallback,
BRANCH_SET_LINK);
else
patch_instruction((struct ppc_inst *)(dest + 1), ppc_inst(instrs[1]));
patch_instruction((struct ppc_inst *)(dest + 2), ppc_inst(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");
}
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((struct ppc_inst *)dest, ppc_inst(instrs[0]));
patch_instruction((struct ppc_inst *)(dest + 1), ppc_inst(instrs[1]));
patch_instruction((struct ppc_inst *)(dest + 2), ppc_inst(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((struct ppc_inst *)dest, ppc_inst(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((struct ppc_inst *)dest, ppc_inst(instr[0]));
patch_instruction((struct ppc_inst *)(dest + 1), ppc_inst(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((struct ppc_inst *)start, ppc_inst(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;
struct ppc_inst *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(PPC_INST_LWSYNC));
}
}
static void do_final_fixups(void)
{
#if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE)
struct ppc_inst inst, *src, *dest, *end;
if (PHYSICAL_START == 0)
return;
src = (struct ppc_inst *)(KERNELBASE + PHYSICAL_START);
dest = (struct ppc_inst *)KERNELBASE;
end = (void *)src + (__end_interrupts - _stext);
while (src < end) {
inst = ppc_inst_read(src);
raw_patch_instruction(dest, inst);
src = ppc_inst_next(src, src);
dest = ppc_inst_next(dest, 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);
}
}
#ifdef CONFIG_PPC64
static void __init test_prefix_patching(void)
{
extern unsigned int ftr_fixup_prefix1[];
extern unsigned int end_ftr_fixup_prefix1[];
extern unsigned int ftr_fixup_prefix1_orig[];
extern unsigned int ftr_fixup_prefix1_expected[];
int size = sizeof(unsigned int) * (end_ftr_fixup_prefix1 - ftr_fixup_prefix1);
fixup.value = fixup.mask = 8;
fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix1 + 1);
fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix1 + 3);
fixup.alt_start_off = fixup.alt_end_off = 0;
/* Sanity check */
check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_orig, size) == 0);
patch_feature_section(0, &fixup);
check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_expected, size) == 0);
check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_orig, size) != 0);
}
static void __init test_prefix_alt_patching(void)
{
extern unsigned int ftr_fixup_prefix2[];
extern unsigned int end_ftr_fixup_prefix2[];
extern unsigned int ftr_fixup_prefix2_orig[];
extern unsigned int ftr_fixup_prefix2_expected[];
extern unsigned int ftr_fixup_prefix2_alt[];
int size = sizeof(unsigned int) * (end_ftr_fixup_prefix2 - ftr_fixup_prefix2);
fixup.value = fixup.mask = 8;
fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix2 + 1);
fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix2 + 3);
fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_prefix2_alt);
fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_prefix2_alt + 2);
/* Sanity check */
check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_orig, size) == 0);
patch_feature_section(0, &fixup);
check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_expected, size) == 0);
check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_orig, size) != 0);
}
static void __init test_prefix_word_alt_patching(void)
{
extern unsigned int ftr_fixup_prefix3[];
extern unsigned int end_ftr_fixup_prefix3[];
extern unsigned int ftr_fixup_prefix3_orig[];
extern unsigned int ftr_fixup_prefix3_expected[];
extern unsigned int ftr_fixup_prefix3_alt[];
int size = sizeof(unsigned int) * (end_ftr_fixup_prefix3 - ftr_fixup_prefix3);
fixup.value = fixup.mask = 8;
fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix3 + 1);
fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix3 + 4);
fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_prefix3_alt);
fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_prefix3_alt + 3);
/* Sanity check */
check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_orig, size) == 0);
patch_feature_section(0, &fixup);
check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_expected, size) == 0);
patch_feature_section(0, &fixup);
check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_orig, size) != 0);
}
#else
static inline void test_prefix_patching(void) {}
static inline void test_prefix_alt_patching(void) {}
static inline void test_prefix_word_alt_patching(void) {}
#endif /* CONFIG_PPC64 */
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();
test_prefix_patching();
test_prefix_alt_patching();
test_prefix_word_alt_patching();
return 0;
}
late_initcall(test_feature_fixups);
#endif /* CONFIG_FTR_FIXUP_SELFTEST */