[PATCH] powerpc/32: Stop printing Kernel virtual memory layout

From: Christophe Leroy
Date: Wed Jan 08 2025 - 13:50:14 EST


Printing of Kernel virtual memory layout was added for debug purpose
by commit f637a49e507c ("powerpc: Minor cleanups of kernel virt
address space definitions")

For security reasons, don't display the kernel's virtual memory layout.

Other architectures have removed it through following commits.

071929dbdd86 ("arm64: Stop printing the virtual memory layout")
1c31d4e96b8c ("ARM: 8820/1: mm: Stop printing the virtual memory layout")
31833332f798 ("m68k/mm: Stop printing the virtual memory layout")
fd8d0ca25631 ("parisc: Hide virtual kernel memory layout")
681ff0181bbf ("x86/mm/init/32: Stop printing the virtual memory layout")

Commit 681ff0181bbf ("x86/mm/init/32: Stop printing the virtual memory
layout") thought x86 was the last one, but in reality powerpc/32 still
had it.

So remove it now on powerpc/32 as well.

Cc: Arvind Sankar <nivedita@xxxxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
arch/powerpc/mm/mem.c | 22 ----------------------
1 file changed, 22 deletions(-)

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index c7708c8fad29..34806c858e54 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -319,28 +319,6 @@ void __init mem_init(void)
per_cpu(next_tlbcam_idx, smp_processor_id()) =
(mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
#endif
-
-#ifdef CONFIG_PPC32
- pr_info("Kernel virtual memory layout:\n");
-#ifdef CONFIG_KASAN
- pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n",
- KASAN_SHADOW_START, KASAN_SHADOW_END);
-#endif
- pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
-#ifdef CONFIG_HIGHMEM
- pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
- PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
-#endif /* CONFIG_HIGHMEM */
- if (ioremap_bot != IOREMAP_TOP)
- pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
- ioremap_bot, IOREMAP_TOP);
- pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
- VMALLOC_START, VMALLOC_END);
-#ifdef MODULES_VADDR
- pr_info(" * 0x%08lx..0x%08lx : modules\n",
- MODULES_VADDR, MODULES_END);
-#endif
-#endif /* CONFIG_PPC32 */
}

void free_initmem(void)
--
2.47.0