Add KASLR to be selected on OCTEON systems.
Signed-off-by: Steven J. Hill <Steven.Hill@xxxxxxxxxx>
---
arch/mips/Kconfig | 3 +-
arch/mips/cavium-octeon/smp.c | 42 ++++++++++++++++++++++
.../asm/mach-cavium-octeon/kernel-entry-init.h | 7 ++--
arch/mips/kernel/relocate.c | 17 +++++++++
arch/mips/kernel/setup.c | 4 ++-
5 files changed, 69 insertions(+), 4 deletions(-)
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 2638856..323d51c 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -892,6 +892,7 @@ config CAVIUM_OCTEON_SOC
select NR_CPUS_DEFAULT_16
select BUILTIN_DTB
select MTD_COMPLEX_MAPPINGS
+ select SYS_SUPPORTS_RELOCATABLE
help
This option supports all of the Octeon reference boards from Cavium
Networks. It builds a kernel that dynamically determines the Octeon
@@ -2535,7 +2536,7 @@ config SYS_SUPPORTS_NUMA
config RELOCATABLE
bool "Relocatable kernel"
- depends on SYS_SUPPORTS_RELOCATABLE && (CPU_MIPS32_R2 || CPU_MIPS64_R2 || CPU_MIPS32_R6 || CPU_MIPS64_R6)
+ depends on SYS_SUPPORTS_RELOCATABLE && (CPU_MIPS32_R2 || CPU_MIPS64_R2 || CPU_MIPS32_R6 || CPU_MIPS64_R6 || CAVIUM_OCTEON_SOC)
help
This builds a kernel image that retains relocation information
so it can be loaded someplace besides the default 1MB.
diff --git a/arch/mips/cavium-octeon/smp.c b/arch/mips/cavium-octeon/smp.c
index 4d457d60..4ac97a3 100644
--- a/arch/mips/cavium-octeon/smp.c
+++ b/arch/mips/cavium-octeon/smp.c
@@ -12,10 +12,12 @@
#include <linux/kernel_stat.h>
#include <linux/sched.h>
#include <linux/module.h>
+#include <linux/bootmem.h>
#include <asm/mmu_context.h>
#include <asm/time.h>
#include <asm/setup.h>
+#include <asm/sections.h>
#include <asm/octeon/octeon.h>
@@ -24,6 +26,7 @@
volatile unsigned long octeon_processor_boot = 0xff;
volatile unsigned long octeon_processor_sp;
volatile unsigned long octeon_processor_gp;
+volatile unsigned long octeon_processor_smpentry;
#ifdef CONFIG_HOTPLUG_CPU
uint64_t octeon_bootloader_entry_addr;
@@ -180,6 +183,23 @@ static void __init octeon_smp_setup(void)
octeon_smp_hotplug_setup();
}
+#ifdef CONFIG_RELOCATABLE
+static long relocation_offset __initdata;
+
+void __init plat_save_relocation(long offset)
+{
+ relocation_offset = offset;
+}
+
+void __init RELOCATE(volatile unsigned long *addr, unsigned long val)
+{
+ unsigned long *p;
+
+ p = (unsigned long *) ((unsigned long)addr - relocation_offset);
+ *p = val;
+}
+#endif
+
/**
* Firmware CPU startup hook
*
@@ -191,9 +211,17 @@ static void octeon_boot_secondary(int cpu, struct task_struct *idle)
pr_info("SMP: Booting CPU%02d (CoreId %2d)...\n", cpu,
cpu_logical_map(cpu));
+#ifndef CONFIG_RELOCATABLE
octeon_processor_sp = __KSTK_TOS(idle);
octeon_processor_gp = (unsigned long)(task_thread_info(idle));
octeon_processor_boot = cpu_logical_map(cpu);
+ octeon_processor_smpentry = (unsigned long)&smp_bootstrap;
+#else
+ RELOCATE(&octeon_processor_sp, __KSTK_TOS(idle));
+ RELOCATE(&octeon_processor_gp, (unsigned long)(task_thread_info(idle)));
+ RELOCATE(&octeon_processor_boot, cpu_logical_map(cpu));
+ RELOCATE(&octeon_processor_smpentry, (unsigned long)&smp_bootstrap);
+#endif
mb();
count = 10000;
@@ -204,6 +232,20 @@ static void octeon_boot_secondary(int cpu, struct task_struct *idle)
}
if (count == 0)
pr_err("Secondary boot timeout\n");
+
+#ifdef CONFIG_RELOCATABLE
+ /*
+ * The last present CPU is now running in the relocated
+ * kernel code. We can free up the bootmem pages.
+ */
+ if ((num_present_cpus() - 1) == cpu) {
+ unsigned long offset;
+
+ offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS);
+ free_bootmem_late(__pa_symbol(VMLINUX_LOAD_ADDRESS), offset);
+ relocation_offset = 0;
+ }
+#endif
}
/**
diff --git a/arch/mips/include/asm/mach-cavium-octeon/kernel-entry-init.h b/arch/mips/include/asm/mach-cavium-octeon/kernel-entry-init.h
index c4873e8..981d072 100644
--- a/arch/mips/include/asm/mach-cavium-octeon/kernel-entry-init.h
+++ b/arch/mips/include/asm/mach-cavium-octeon/kernel-entry-init.h
@@ -113,6 +113,9 @@ octeon_spin_wait_boot:
# Get my SP from the global variable
PTR_LA t0, octeon_processor_sp
LONG_L sp, (t0)
+ # Get my SMPENTRY target from the global variable
+ PTR_LA t0, octeon_processor_smpentry
+ LONG_L t1, (t0)
# Set the SP global variable to zero so the master knows we've started
LONG_S zero, (t0)
#ifdef __OCTEON__
@@ -121,8 +124,8 @@ octeon_spin_wait_boot:
#else
sync
#endif
- # Jump to the normal Linux SMP entry point
- j smp_bootstrap
+ # Jump to the normal Linux SMP entry point (smp_bootstrap)
+ jr t1
nop
#else /* CONFIG_SMP */
diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c
index ca1cc30..250ff9c 100644
--- a/arch/mips/kernel/relocate.c
+++ b/arch/mips/kernel/relocate.c
@@ -31,6 +31,20 @@ extern u32 _relocation_end[]; /* End relocation table */
extern long __start___ex_table; /* Start exception table */
extern long __stop___ex_table; /* End exception table */
+
+/*
+ * Declare this function weak so the platform can choose if they
+ * want the kernel relocation offset.
+ *
+ * WARNING!!! This is a potential security risk if the platform
+ * function does not zero out the value before getting
+ * to userspace!
+ */
+void __weak plat_save_relocation(long offset)
+{
+ /* Do nothing... */
+}
+
static inline u32 __init get_synci_step(void)
{
u32 res;
@@ -316,6 +330,9 @@ void *__init relocate_kernel(void)
arcs_cmdline[0] = '\0';
if (offset) {
+ /* Save the relocation offset value. */
+ plat_save_relocation(offset);
+
/* Copy the kernel to it's new location */
memcpy(loc_new, &_text, kernel_length);
diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 36cf8d6..582c711 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -501,11 +501,13 @@ static void __init bootmem_init(void)
* between the original and new locations may be returned to the system.
*/
if (__pa_symbol(_text) > __pa_symbol(VMLINUX_LOAD_ADDRESS)) {
- unsigned long offset;
extern void show_kernel_relocation(const char *level);
+#ifndef CONFIG_CAVIUM_OCTEON_SOC
+ unsigned long offset;
offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS);
free_bootmem(__pa_symbol(VMLINUX_LOAD_ADDRESS), offset);
+#endif
#if defined(CONFIG_DEBUG_KERNEL) && defined(CONFIG_DEBUG_INFO)
/*
--
1.9.1
