Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (29 commits)
  powerpc/83xx: Move mcu_mpc8349emitx driver out of drivers/i2c/chips/
  powerpc/83xx: Make serial ports work on MPC8315E-RDB w/ FSL U-Boots
  powerpc/e500mc: Doorbells need to be taken w/exceptions disabled
  powerpc: Enable PS3 options and QPACE in ppc64_defconfig
  powerpc/powermac: Fix occasional SMP boot failure
  powerpc/cacheinfo: Rename cache_dir per-cpu variable
  hvc_console: Use kzalloc() instead of kmalloc() + memset()
  hvc_console: Do not set low_latency when using interrupts
  hvc_console: Call free_irq() only if request_irq() was successful
  hvc_console: Change an mb() to smp_mb() and add some comments
  powerpc: Cleanup from l64 to ll64 change: drivers/net
  powerpc: Cleanup from l64 to ll64 change: drivers/char
  powerpc: Cleanup from l64 to ll64 change: arch code
  powerpc: Change u64/s64 to a long long integer type
  powerpc/kexec: Check crash_base for relocatable kernel
  powerpc: Make dummy section a valid note header
  Xilinx: SPI: updated driver for device tree
  drivers/of: Add the of_find_i2c_device_by_node function.
  powerpc/xsysace: add compatible string for non-ipcore instance
  powerpc/mpc52xx: remove dead code from GPIO driver
  ...

1 files changed, 25 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/machine_kexec.c b/arch/powerpc/kernel/machine_kexec.c
index b3abebb7ee6..d59e2b1bdcb 100644
--- a/arch/powerpc/kernel/machine_kexec.c
+++ b/arch/powerpc/kernel/machine_kexec.c
@@ -93,10 +93,35 @@ void __init reserve_crashkernel(void)
 				KDUMP_KERNELBASE);
 
 	crashk_res.start = KDUMP_KERNELBASE;
+#else
+	if (!crashk_res.start) {
+		/*
+		 * unspecified address, choose a region of specified size
+		 * can overlap with initrd (ignoring corruption when retained)
+		 * ppc64 requires kernel and some stacks to be in first segemnt
+		 */
+		crashk_res.start = KDUMP_KERNELBASE;
+	}
+
+	crash_base = PAGE_ALIGN(crashk_res.start);
+	if (crash_base != crashk_res.start) {
+		printk("Crash kernel base must be aligned to 0x%lx\n",
+				PAGE_SIZE);
+		crashk_res.start = crash_base;
+	}
+
 #endif
 	crash_size = PAGE_ALIGN(crash_size);
 	crashk_res.end = crashk_res.start + crash_size - 1;
 
+	/* The crash region must not overlap the current kernel */
+	if (overlaps_crashkernel(__pa(_stext), _end - _stext)) {
+		printk(KERN_WARNING
+			"Crash kernel can not overlap current kernel\n");
+		crashk_res.start = crashk_res.end = 0;
+		return;
+	}
+
 	/* Crash kernel trumps memory limit */
 	if (memory_limit && memory_limit <= crashk_res.end) {
 		memory_limit = crashk_res.end + 1;