Commit 5d5c4533 authored by Ritesh Harjani (IBM)'s avatar Ritesh Harjani (IBM) Committed by Liao Chen
Browse files

powerpc/fadump: Move fadump_cma_init to setup_arch() after initmem_init() 

stable inclusion
from stable-v6.6.64
commit c5c1d1ef70834013fc3bd12b6a0f4664c6d75a74
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBEDPC

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c5c1d1ef70834013fc3bd12b6a0f4664c6d75a74



--------------------------------

[ Upstream commit 05b94cae1c47f94588c3e7096963c1007c4d9c1d ]

During early init CMA_MIN_ALIGNMENT_BYTES can be PAGE_SIZE,
since pageblock_order is still zero and it gets initialized
later during initmem_init() e.g.
setup_arch() -> initmem_init() -> sparse_init() -> set_pageblock_order()

One such use case where this causes issue is -
early_setup() -> early_init_devtree() -> fadump_reserve_mem() -> fadump_cma_init()

This causes CMA memory alignment check to be bypassed in
cma_init_reserved_mem(). Then later cma_activate_area() can hit
a VM_BUG_ON_PAGE(pfn & ((1 << order) - 1)) if the reserved memory
area was not pageblock_order aligned.

Fix it by moving the fadump_cma_init() after initmem_init(),
where other such cma reservations also gets called.

<stack trace>
==============
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10010
flags: 0x13ffff800000000(node=1|zone=0|lastcpupid=0x7ffff) CMA
raw: 013ffff800000000 5deadbeef0000100 5deadbeef0000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: VM_BUG_ON_PAGE(pfn & ((1 << order) - 1))
------------[ cut here ]------------
kernel BUG at mm/page_alloc.c:778!

Call Trace:
__free_one_page+0x57c/0x7b0 (unreliable)
free_pcppages_bulk+0x1a8/0x2c8
free_unref_page_commit+0x3d4/0x4e4
free_unref_page+0x458/0x6d0
init_cma_reserved_pageblock+0x114/0x198
cma_init_reserved_areas+0x270/0x3e0
do_one_initcall+0x80/0x2f8
kernel_init_freeable+0x33c/0x530
kernel_init+0x34/0x26c
ret_from_kernel_user_thread+0x14/0x1c

Fixes: 11ac3e87 ("mm: cma: use pageblock_order as the single alignment")
Suggested-by: default avatarDavid Hildenbrand <david@redhat.com>
Reported-by: default avatarSachin P Bappalige <sachinpb@linux.ibm.com>
Acked-by: default avatarHari Bathini <hbathini@linux.ibm.com>
Reviewed-by: default avatarMadhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: default avatarRitesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/3ae208e48c0d9cefe53d2dc4f593388067405b7d.1729146153.git.ritesh.list@gmail.com


Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
Signed-off-by: default avatarZhangPeng <zhangpeng362@huawei.com>
Signed-off-by: default avatarLiao Chen <liaochen4@huawei.com>
parent 11187703

arch/powerpc/include/asm/fadump.h

+7 −0
Original line number Diff line number Diff line
@@ -32,4 +32,11 @@ extern int early_init_dt_scan_fw_dump(unsigned long node, const char *uname, 
				      int depth, void *data);

extern int fadump_reserve_mem(void);

#endif



#if defined(CONFIG_FA_DUMP) && defined(CONFIG_CMA)

void fadump_cma_init(void);

#else

static inline void fadump_cma_init(void) { }

#endif



#endif /* _ASM_POWERPC_FADUMP_H */

arch/powerpc/kernel/fadump.c

+1 −5
Original line number Diff line number Diff line
@@ -80,7 +80,7 @@ static struct cma *fadump_cma; 
 * But for some reason even if it fails we still have the memory reservation

 * with us and we can still continue doing fadump.

 */

static void __init fadump_cma_init(void)

void __init fadump_cma_init(void)

{

	unsigned long long base, size;

	int rc;
@@ -124,8 +124,6 @@ static void __init fadump_cma_init(void) 
		(unsigned long)cma_get_base(fadump_cma) >> 20,

		fw_dump.reserve_dump_area_size);

}

#else

static void __init fadump_cma_init(void) { }

#endif /* CONFIG_CMA */



/* Scan the Firmware Assisted dump configuration details. */
@@ -642,8 +640,6 @@ int __init fadump_reserve_mem(void) 


		pr_info("Reserved %lldMB of memory at %#016llx (System RAM: %lldMB)\n",

			(size >> 20), base, (memblock_phys_mem_size() >> 20));



		fadump_cma_init();

	}



	return ret;

arch/powerpc/kernel/setup-common.c

+4 −2
Original line number Diff line number Diff line
@@ -988,9 +988,11 @@ void __init setup_arch(char **cmdline_p) 
	initmem_init();



	/*

	 * Reserve large chunks of memory for use by CMA for KVM and hugetlb. These must

	 * be called after initmem_init(), so that pageblock_order is initialised.

	 * Reserve large chunks of memory for use by CMA for fadump, KVM and

	 * hugetlb. These must be called after initmem_init(), so that

	 * pageblock_order is initialised.

	 */

	fadump_cma_init();

	kvm_cma_reserve();

	gigantic_hugetlb_cma_reserve();