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authorSteven J. Hill <steven.hill@cavium.com>2016-12-13 23:25:37 +0300
committerRalf Baechle <ralf@linux-mips.org>2017-01-03 18:34:35 +0300
commit3ff72be4c9ce269c5b7adff9b0f912a2df3cb987 (patch)
tree24c14cb9ca8c081670310277b252ea3c9027bf30 /arch/mips/cavium-octeon/smp.c
parent126c1113bf3e6facdd5562064043b9e8fa8c9bf1 (diff)
downloadlinux-3ff72be4c9ce269c5b7adff9b0f912a2df3cb987.tar.xz
MIPS: Octeon: Enable KASLR
This patch enables KASLR for Octeon systems. The SMP startup code is such that the secondaries monitor the volatile variable 'octeon_processor_relocated_kernel_entry' for any non-zero value. The 'plat_post_relocation hook' is used to set that value to the kernel entry point of the relocated kernel. The secondary CPUs will then jusmp to the new kernel, perform their initialization again and begin waiting for the boot CPU to start them via the relocated loop 'octeon_spin_wait_boot'. Inspired by Steven's code from Cavium. Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com> Signed-off-by: Steven J. Hill <steven.hill@cavium.com> Acked-by: David Daney <david.daney@cavium.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/14669/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/cavium-octeon/smp.c')
-rw-r--r--arch/mips/cavium-octeon/smp.c20
1 files changed, 18 insertions, 2 deletions
diff --git a/arch/mips/cavium-octeon/smp.c b/arch/mips/cavium-octeon/smp.c
index 256fe6f65cf2..889c3f49dbc0 100644
--- a/arch/mips/cavium-octeon/smp.c
+++ b/arch/mips/cavium-octeon/smp.c
@@ -24,12 +24,17 @@
volatile unsigned long octeon_processor_boot = 0xff;
volatile unsigned long octeon_processor_sp;
volatile unsigned long octeon_processor_gp;
+#ifdef CONFIG_RELOCATABLE
+volatile unsigned long octeon_processor_relocated_kernel_entry;
+#endif /* CONFIG_RELOCATABLE */
#ifdef CONFIG_HOTPLUG_CPU
uint64_t octeon_bootloader_entry_addr;
EXPORT_SYMBOL(octeon_bootloader_entry_addr);
#endif
+extern void kernel_entry(unsigned long arg1, ...);
+
static void octeon_icache_flush(void)
{
asm volatile ("synci 0($0)\n");
@@ -180,6 +185,19 @@ static void __init octeon_smp_setup(void)
octeon_smp_hotplug_setup();
}
+
+#ifdef CONFIG_RELOCATABLE
+int plat_post_relocation(long offset)
+{
+ unsigned long entry = (unsigned long)kernel_entry;
+
+ /* Send secondaries into relocated kernel */
+ octeon_processor_relocated_kernel_entry = entry + offset;
+
+ return 0;
+}
+#endif /* CONFIG_RELOCATABLE */
+
/**
* Firmware CPU startup hook
*
@@ -333,8 +351,6 @@ void play_dead(void)
;
}
-extern void kernel_entry(unsigned long arg1, ...);
-
static void start_after_reset(void)
{
kernel_entry(0, 0, 0); /* set a2 = 0 for secondary core */