Re: [PATCH v2 05/15] MIPS: KASLR: Drop relocatable fixup from reservation_init

From: Matt Redfearn
Date: Tue Feb 13 2018 - 06:37:39 EST


Hi Serge,

On 02/02/18 03:54, Serge Semin wrote:
From: Matt Redfearn <matt.redfearn@xxxxxxxx>

A recent change ("MIPS: memblock: Discard bootmem initialization")
removed the reservation of all memory below the kernel's _end symbol in
bootmem. This makes the call to free_bootmem unnecessary, since the
memory region is no longer marked reserved.

Additionally, ("MIPS: memblock: Print out kernel virtual mem
layout") added a display of the kernel's virtual memory layout, so
printing the relocation information at this point is redundant.

Remove this section of code.

Signed-off-by: Matt Redfearn <matt.redfearn@xxxxxxxx>

Missing your SoB.

I think this change should go after you introduce the new mechanism, i.e. after "MIPS: memblock: Print out kernel virtual mem layout", which should probably go nearer the start of the series.

Thanks,
Matt

---
arch/mips/kernel/setup.c | 23 -----------------------
1 file changed, 23 deletions(-)

diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index b5fcacf71b3f..cf3674977170 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -528,29 +528,6 @@ static void __init bootmem_init(void)
memory_present(0, start, end);
}
-#ifdef CONFIG_RELOCATABLE
- /*
- * The kernel reserves all memory below its _end symbol as bootmem,
- * but the kernel may now be at a much higher address. The memory
- * 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);
-
- offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS);
- free_bootmem(__pa_symbol(VMLINUX_LOAD_ADDRESS), offset);
-
-#if defined(CONFIG_DEBUG_KERNEL) && defined(CONFIG_DEBUG_INFO)
- /*
- * This information is necessary when debugging the kernel
- * But is a security vulnerability otherwise!
- */
- show_kernel_relocation(KERN_INFO);
-#endif
- }
-#endif
-
/*
* Reserve initrd memory if needed.
*/