* Re: [PATCHv3] efi: apply memblock cap after memblock_add()
2021-12-15 2:13 ` [PATCHv3] " Pingfan Liu
@ 2021-12-15 3:58 ` Leizhen (ThunderTown)
2021-12-15 5:29 ` Pingfan Liu
2021-12-17 15:08 ` Rob Herring
` (2 subsequent siblings)
3 siblings, 1 reply; 17+ messages in thread
From: Leizhen (ThunderTown) @ 2021-12-15 3:58 UTC (permalink / raw)
To: Pingfan Liu, devicetree, linux-efi
Cc: Rob Herring, Catalin Marinas, Will Deacon, Andrew Morton,
Mike Rapoport, Geert Uytterhoeven, Frank Rowand, Ard Biesheuvel,
Nick Terrell, linux-arm-kernel
On 2021/12/15 10:13, Pingfan Liu wrote:
> On arm64, during kdump kernel saves vmcore, it runs into the following bug:
> ...
> [ 15.148919] usercopy: Kernel memory exposure attempt detected from SLUB object 'kmem_cache_node' (offset 0, size 4096)!
> [ 15.159707] ------------[ cut here ]------------
> [ 15.164311] kernel BUG at mm/usercopy.c:99!
> [ 15.168482] Internal error: Oops - BUG: 0 [#1] SMP
> [ 15.173261] Modules linked in: xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce sbsa_gwdt ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm_ttm_helper ttm drm nvme nvme_core xgene_hwmon i2c_designware_platform i2c_designware_core dm_mirror dm_region_hash dm_log dm_mod overlay squashfs zstd_decompress loop
> [ 15.206186] CPU: 0 PID: 542 Comm: cp Not tainted 5.16.0-rc4 #1
> [ 15.212006] Hardware name: GIGABYTE R272-P30-JG/MP32-AR0-JG, BIOS F12 (SCP: 1.5.20210426) 05/13/2021
> [ 15.221125] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> [ 15.228073] pc : usercopy_abort+0x9c/0xa0
> [ 15.232074] lr : usercopy_abort+0x9c/0xa0
> [ 15.236070] sp : ffff8000121abba0
> [ 15.239371] x29: ffff8000121abbb0 x28: 0000000000003000 x27: 0000000000000000
> [ 15.246494] x26: 0000000080000400 x25: 0000ffff885c7000 x24: 0000000000000000
> [ 15.253617] x23: 000007ff80400000 x22: ffff07ff80401000 x21: 0000000000000001
> [ 15.260739] x20: 0000000000001000 x19: ffff07ff80400000 x18: ffffffffffffffff
> [ 15.267861] x17: 656a626f2042554c x16: 53206d6f72662064 x15: 6574636574656420
> [ 15.274983] x14: 74706d6574746120 x13: 2129363930342065 x12: 7a6973202c302074
> [ 15.282105] x11: ffffc8b041d1b148 x10: 00000000ffff8000 x9 : ffffc8b04012812c
> [ 15.289228] x8 : 00000000ffff7fff x7 : ffffc8b041d1b148 x6 : 0000000000000000
> [ 15.296349] x5 : 0000000000000000 x4 : 0000000000007fff x3 : 0000000000000000
> [ 15.303471] x2 : 0000000000000000 x1 : ffff07ff8c064800 x0 : 000000000000006b
> [ 15.310593] Call trace:
> [ 15.313027] usercopy_abort+0x9c/0xa0
> [ 15.316677] __check_heap_object+0xd4/0xf0
> [ 15.320762] __check_object_size.part.0+0x160/0x1e0
> [ 15.325628] __check_object_size+0x2c/0x40
> [ 15.329711] copy_oldmem_page+0x7c/0x140
> [ 15.333623] read_from_oldmem.part.0+0xfc/0x1c0
> [ 15.338142] __read_vmcore.constprop.0+0x23c/0x350
> [ 15.342920] read_vmcore+0x28/0x34
> [ 15.346309] proc_reg_read+0xb4/0xf0
> [ 15.349871] vfs_read+0xb8/0x1f0
> [ 15.353088] ksys_read+0x74/0x100
> [ 15.356390] __arm64_sys_read+0x28/0x34
> ...
>
> This bug introduced by commit b261dba2fdb2 ("arm64: kdump: Remove custom
> linux,usable-memory-range handling"), which moves
> memblock_cap_memory_range() to fdt, but it breaches the rules that
> memblock_cap_memory_range() should come after memblock_add() etc as said
> in commit e888fa7bb882 ("memblock: Check memory add/cap ordering").
void __init early_init_dt_scan_nodes(void)
{
//(1) -->early_init_dt_check_for_usable_mem_range, fill cap_mem_addr
rc = of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
//(2) --> early_init_dt_add_memory_arch --> memblock_add()
of_scan_flat_dt(early_init_dt_scan_memory, NULL);
//(3)
memblock_cap_memory_range(cap_mem_addr, cap_mem_size);
}
I didn't get it. The above step (1),(2),(3) comply with
commit e888fa7bb882 ("memblock: Check memory add/cap ordering")
Did you see the warning?
pr_warn("%s: No memory registered yet\n", __func__);
>
> As a consequence, the virtual address set up by copy_oldmem_page() does
> not bail out from the test of virt_addr_valid() in check_heap_object(),
> and finally hits the BUG_ON().
>
> Since memblock allocator has no idea about when the memblock is fully
> populated, while efi_init() is aware, so tackling this issue by calling the
> interface early_init_dt_check_for_usable_mem_range() exposed by of/fdt.
>
> Fixes: b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling")
> Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Zhen Lei <thunder.leizhen@huawei.com>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will@kernel.org>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Mike Rapoport <rppt@kernel.org>
> Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> Cc: Frank Rowand <frowand.list@gmail.com>
> Cc: Ard Biesheuvel <ardb@kernel.org>
> Cc: Nick Terrell <terrelln@fb.com>
> Cc: linux-arm-kernel@lists.infradead.org
> To: devicetree@vger.kernel.org
> To: linux-efi@vger.kernel.org
> ---
> v2 -> v3:
> use static inline stub to avoid #ifdef according to Rob's suggestion
>
> drivers/firmware/efi/efi-init.c | 5 +++++
> drivers/of/fdt.c | 2 +-
> include/linux/of_fdt.h | 2 ++
> 3 files changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c
> index b19ce1a83f91..b2c829e95bd1 100644
> --- a/drivers/firmware/efi/efi-init.c
> +++ b/drivers/firmware/efi/efi-init.c
> @@ -235,6 +235,11 @@ void __init efi_init(void)
> }
>
> reserve_regions();
> + /*
> + * For memblock manipulation, the cap should come after the memblock_add().
> + * And now, memblock is fully populated, it is time to do capping.
> + */
> + early_init_dt_check_for_usable_mem_range();
> efi_esrt_init();
> efi_mokvar_table_init();
>
> diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
> index 18a2df431bfd..aa07ef5cab5f 100644
> --- a/drivers/of/fdt.c
> +++ b/drivers/of/fdt.c
> @@ -972,7 +972,7 @@ static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND;
> * location from flat tree
> * @node: reference to node containing usable memory range location ('chosen')
> */
> -static void __init early_init_dt_check_for_usable_mem_range(void)
> +void __init early_init_dt_check_for_usable_mem_range(void)
> {
> const __be32 *prop;
> int len;
> diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
> index cf48983d3c86..ad09beb6d13c 100644
> --- a/include/linux/of_fdt.h
> +++ b/include/linux/of_fdt.h
> @@ -62,6 +62,7 @@ extern int early_init_dt_scan_chosen(unsigned long node, const char *uname,
> int depth, void *data);
> extern int early_init_dt_scan_memory(unsigned long node, const char *uname,
> int depth, void *data);
> +extern void early_init_dt_check_for_usable_mem_range(void);
> extern int early_init_dt_scan_chosen_stdout(void);
> extern void early_init_fdt_scan_reserved_mem(void);
> extern void early_init_fdt_reserve_self(void);
> @@ -86,6 +87,7 @@ extern void unflatten_and_copy_device_tree(void);
> extern void early_init_devtree(void *);
> extern void early_get_first_memblock_info(void *, phys_addr_t *);
> #else /* CONFIG_OF_EARLY_FLATTREE */
> +static inline void early_init_dt_check_for_usable_mem_range(void) {}
> static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; }
> static inline void early_init_fdt_scan_reserved_mem(void) {}
> static inline void early_init_fdt_reserve_self(void) {}
>
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCHv3] efi: apply memblock cap after memblock_add()
2021-12-15 3:58 ` Leizhen (ThunderTown)
@ 2021-12-15 5:29 ` Pingfan Liu
2021-12-15 6:53 ` Leizhen (ThunderTown)
0 siblings, 1 reply; 17+ messages in thread
From: Pingfan Liu @ 2021-12-15 5:29 UTC (permalink / raw)
To: Leizhen (ThunderTown)
Cc: devicetree, linux-efi, Rob Herring, Catalin Marinas, Will Deacon,
Andrew Morton, Mike Rapoport, Geert Uytterhoeven, Frank Rowand,
Ard Biesheuvel, Nick Terrell, linux-arm-kernel
On Wed, Dec 15, 2021 at 11:58:03AM +0800, Leizhen (ThunderTown) wrote:
>
>
> On 2021/12/15 10:13, Pingfan Liu wrote:
> > On arm64, during kdump kernel saves vmcore, it runs into the following bug:
> > ...
> > [ 15.148919] usercopy: Kernel memory exposure attempt detected from SLUB object 'kmem_cache_node' (offset 0, size 4096)!
> > [ 15.159707] ------------[ cut here ]------------
> > [ 15.164311] kernel BUG at mm/usercopy.c:99!
> > [ 15.168482] Internal error: Oops - BUG: 0 [#1] SMP
> > [ 15.173261] Modules linked in: xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce sbsa_gwdt ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm_ttm_helper ttm drm nvme nvme_core xgene_hwmon i2c_designware_platform i2c_designware_core dm_mirror dm_region_hash dm_log dm_mod overlay squashfs zstd_decompress loop
> > [ 15.206186] CPU: 0 PID: 542 Comm: cp Not tainted 5.16.0-rc4 #1
> > [ 15.212006] Hardware name: GIGABYTE R272-P30-JG/MP32-AR0-JG, BIOS F12 (SCP: 1.5.20210426) 05/13/2021
> > [ 15.221125] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> > [ 15.228073] pc : usercopy_abort+0x9c/0xa0
> > [ 15.232074] lr : usercopy_abort+0x9c/0xa0
> > [ 15.236070] sp : ffff8000121abba0
> > [ 15.239371] x29: ffff8000121abbb0 x28: 0000000000003000 x27: 0000000000000000
> > [ 15.246494] x26: 0000000080000400 x25: 0000ffff885c7000 x24: 0000000000000000
> > [ 15.253617] x23: 000007ff80400000 x22: ffff07ff80401000 x21: 0000000000000001
> > [ 15.260739] x20: 0000000000001000 x19: ffff07ff80400000 x18: ffffffffffffffff
> > [ 15.267861] x17: 656a626f2042554c x16: 53206d6f72662064 x15: 6574636574656420
> > [ 15.274983] x14: 74706d6574746120 x13: 2129363930342065 x12: 7a6973202c302074
> > [ 15.282105] x11: ffffc8b041d1b148 x10: 00000000ffff8000 x9 : ffffc8b04012812c
> > [ 15.289228] x8 : 00000000ffff7fff x7 : ffffc8b041d1b148 x6 : 0000000000000000
> > [ 15.296349] x5 : 0000000000000000 x4 : 0000000000007fff x3 : 0000000000000000
> > [ 15.303471] x2 : 0000000000000000 x1 : ffff07ff8c064800 x0 : 000000000000006b
> > [ 15.310593] Call trace:
> > [ 15.313027] usercopy_abort+0x9c/0xa0
> > [ 15.316677] __check_heap_object+0xd4/0xf0
> > [ 15.320762] __check_object_size.part.0+0x160/0x1e0
> > [ 15.325628] __check_object_size+0x2c/0x40
> > [ 15.329711] copy_oldmem_page+0x7c/0x140
> > [ 15.333623] read_from_oldmem.part.0+0xfc/0x1c0
> > [ 15.338142] __read_vmcore.constprop.0+0x23c/0x350
> > [ 15.342920] read_vmcore+0x28/0x34
> > [ 15.346309] proc_reg_read+0xb4/0xf0
> > [ 15.349871] vfs_read+0xb8/0x1f0
> > [ 15.353088] ksys_read+0x74/0x100
> > [ 15.356390] __arm64_sys_read+0x28/0x34
> > ...
> >
> > This bug introduced by commit b261dba2fdb2 ("arm64: kdump: Remove custom
> > linux,usable-memory-range handling"), which moves
> > memblock_cap_memory_range() to fdt, but it breaches the rules that
> > memblock_cap_memory_range() should come after memblock_add() etc as said
> > in commit e888fa7bb882 ("memblock: Check memory add/cap ordering").
>
> void __init early_init_dt_scan_nodes(void)
> {
> //(1) -->early_init_dt_check_for_usable_mem_range, fill cap_mem_addr
> rc = of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
>
> //(2) --> early_init_dt_add_memory_arch --> memblock_add()
> of_scan_flat_dt(early_init_dt_scan_memory, NULL);
>
> //(3)
> memblock_cap_memory_range(cap_mem_addr, cap_mem_size);
> }
>
> I didn't get it. The above step (1),(2),(3) comply with
> commit e888fa7bb882 ("memblock: Check memory add/cap ordering")
>
Well, at this scope, it does. But from a larger scope, let's say on
arm64,
setup_arch
...
setup_machine_fdt(); //which holds your case
...
efi_init(); //which call memblock_add, and breach the ordering.
> Did you see the warning?
> pr_warn("%s: No memory registered yet\n", __func__);
>
Yes, I did see this message, which brings me to commit e888fa7bb882
("memblock: Check memory add/cap ordering")
I am also curious why this bug does not be discovered. Is CONFIG_EFI
on at your case?
Thanks,
Pingfan
> >
> > As a consequence, the virtual address set up by copy_oldmem_page() does
> > not bail out from the test of virt_addr_valid() in check_heap_object(),
> > and finally hits the BUG_ON().
> >
> > Since memblock allocator has no idea about when the memblock is fully
> > populated, while efi_init() is aware, so tackling this issue by calling the
> > interface early_init_dt_check_for_usable_mem_range() exposed by of/fdt.
> >
> > Fixes: b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling")
> > Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
> > Cc: Rob Herring <robh+dt@kernel.org>
> > Cc: Zhen Lei <thunder.leizhen@huawei.com>
> > Cc: Catalin Marinas <catalin.marinas@arm.com>
> > Cc: Will Deacon <will@kernel.org>
> > Cc: Andrew Morton <akpm@linux-foundation.org>
> > Cc: Mike Rapoport <rppt@kernel.org>
> > Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> > Cc: Frank Rowand <frowand.list@gmail.com>
> > Cc: Ard Biesheuvel <ardb@kernel.org>
> > Cc: Nick Terrell <terrelln@fb.com>
> > Cc: linux-arm-kernel@lists.infradead.org
> > To: devicetree@vger.kernel.org
> > To: linux-efi@vger.kernel.org
> > ---
> > v2 -> v3:
> > use static inline stub to avoid #ifdef according to Rob's suggestion
> >
> > drivers/firmware/efi/efi-init.c | 5 +++++
> > drivers/of/fdt.c | 2 +-
> > include/linux/of_fdt.h | 2 ++
> > 3 files changed, 8 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c
> > index b19ce1a83f91..b2c829e95bd1 100644
> > --- a/drivers/firmware/efi/efi-init.c
> > +++ b/drivers/firmware/efi/efi-init.c
> > @@ -235,6 +235,11 @@ void __init efi_init(void)
> > }
> >
> > reserve_regions();
> > + /*
> > + * For memblock manipulation, the cap should come after the memblock_add().
> > + * And now, memblock is fully populated, it is time to do capping.
> > + */
> > + early_init_dt_check_for_usable_mem_range();
> > efi_esrt_init();
> > efi_mokvar_table_init();
> >
> > diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
> > index 18a2df431bfd..aa07ef5cab5f 100644
> > --- a/drivers/of/fdt.c
> > +++ b/drivers/of/fdt.c
> > @@ -972,7 +972,7 @@ static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND;
> > * location from flat tree
> > * @node: reference to node containing usable memory range location ('chosen')
> > */
> > -static void __init early_init_dt_check_for_usable_mem_range(void)
> > +void __init early_init_dt_check_for_usable_mem_range(void)
> > {
> > const __be32 *prop;
> > int len;
> > diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
> > index cf48983d3c86..ad09beb6d13c 100644
> > --- a/include/linux/of_fdt.h
> > +++ b/include/linux/of_fdt.h
> > @@ -62,6 +62,7 @@ extern int early_init_dt_scan_chosen(unsigned long node, const char *uname,
> > int depth, void *data);
> > extern int early_init_dt_scan_memory(unsigned long node, const char *uname,
> > int depth, void *data);
> > +extern void early_init_dt_check_for_usable_mem_range(void);
> > extern int early_init_dt_scan_chosen_stdout(void);
> > extern void early_init_fdt_scan_reserved_mem(void);
> > extern void early_init_fdt_reserve_self(void);
> > @@ -86,6 +87,7 @@ extern void unflatten_and_copy_device_tree(void);
> > extern void early_init_devtree(void *);
> > extern void early_get_first_memblock_info(void *, phys_addr_t *);
> > #else /* CONFIG_OF_EARLY_FLATTREE */
> > +static inline void early_init_dt_check_for_usable_mem_range(void) {}
> > static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; }
> > static inline void early_init_fdt_scan_reserved_mem(void) {}
> > static inline void early_init_fdt_reserve_self(void) {}
> >
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCHv3] efi: apply memblock cap after memblock_add()
2021-12-15 5:29 ` Pingfan Liu
@ 2021-12-15 6:53 ` Leizhen (ThunderTown)
2021-12-15 8:24 ` Pingfan Liu
2021-12-15 15:05 ` Rob Herring
0 siblings, 2 replies; 17+ messages in thread
From: Leizhen (ThunderTown) @ 2021-12-15 6:53 UTC (permalink / raw)
To: Pingfan Liu
Cc: devicetree, linux-efi, Rob Herring, Catalin Marinas, Will Deacon,
Andrew Morton, Mike Rapoport, Geert Uytterhoeven, Frank Rowand,
Ard Biesheuvel, Nick Terrell, linux-arm-kernel
On 2021/12/15 13:29, Pingfan Liu wrote:
> On Wed, Dec 15, 2021 at 11:58:03AM +0800, Leizhen (ThunderTown) wrote:
>>
>>
>> On 2021/12/15 10:13, Pingfan Liu wrote:
>>> On arm64, during kdump kernel saves vmcore, it runs into the following bug:
>>> ...
>>> [ 15.148919] usercopy: Kernel memory exposure attempt detected from SLUB object 'kmem_cache_node' (offset 0, size 4096)!
>>> [ 15.159707] ------------[ cut here ]------------
>>> [ 15.164311] kernel BUG at mm/usercopy.c:99!
>>> [ 15.168482] Internal error: Oops - BUG: 0 [#1] SMP
>>> [ 15.173261] Modules linked in: xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce sbsa_gwdt ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm_ttm_helper ttm drm nvme nvme_core xgene_hwmon i2c_designware_platform i2c_designware_core dm_mirror dm_region_hash dm_log dm_mod overlay squashfs zstd_decompress loop
>>> [ 15.206186] CPU: 0 PID: 542 Comm: cp Not tainted 5.16.0-rc4 #1
>>> [ 15.212006] Hardware name: GIGABYTE R272-P30-JG/MP32-AR0-JG, BIOS F12 (SCP: 1.5.20210426) 05/13/2021
>>> [ 15.221125] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
>>> [ 15.228073] pc : usercopy_abort+0x9c/0xa0
>>> [ 15.232074] lr : usercopy_abort+0x9c/0xa0
>>> [ 15.236070] sp : ffff8000121abba0
>>> [ 15.239371] x29: ffff8000121abbb0 x28: 0000000000003000 x27: 0000000000000000
>>> [ 15.246494] x26: 0000000080000400 x25: 0000ffff885c7000 x24: 0000000000000000
>>> [ 15.253617] x23: 000007ff80400000 x22: ffff07ff80401000 x21: 0000000000000001
>>> [ 15.260739] x20: 0000000000001000 x19: ffff07ff80400000 x18: ffffffffffffffff
>>> [ 15.267861] x17: 656a626f2042554c x16: 53206d6f72662064 x15: 6574636574656420
>>> [ 15.274983] x14: 74706d6574746120 x13: 2129363930342065 x12: 7a6973202c302074
>>> [ 15.282105] x11: ffffc8b041d1b148 x10: 00000000ffff8000 x9 : ffffc8b04012812c
>>> [ 15.289228] x8 : 00000000ffff7fff x7 : ffffc8b041d1b148 x6 : 0000000000000000
>>> [ 15.296349] x5 : 0000000000000000 x4 : 0000000000007fff x3 : 0000000000000000
>>> [ 15.303471] x2 : 0000000000000000 x1 : ffff07ff8c064800 x0 : 000000000000006b
>>> [ 15.310593] Call trace:
>>> [ 15.313027] usercopy_abort+0x9c/0xa0
>>> [ 15.316677] __check_heap_object+0xd4/0xf0
>>> [ 15.320762] __check_object_size.part.0+0x160/0x1e0
>>> [ 15.325628] __check_object_size+0x2c/0x40
>>> [ 15.329711] copy_oldmem_page+0x7c/0x140
>>> [ 15.333623] read_from_oldmem.part.0+0xfc/0x1c0
>>> [ 15.338142] __read_vmcore.constprop.0+0x23c/0x350
>>> [ 15.342920] read_vmcore+0x28/0x34
>>> [ 15.346309] proc_reg_read+0xb4/0xf0
>>> [ 15.349871] vfs_read+0xb8/0x1f0
>>> [ 15.353088] ksys_read+0x74/0x100
>>> [ 15.356390] __arm64_sys_read+0x28/0x34
>>> ...
>>>
>>> This bug introduced by commit b261dba2fdb2 ("arm64: kdump: Remove custom
>>> linux,usable-memory-range handling"), which moves
>>> memblock_cap_memory_range() to fdt, but it breaches the rules that
>>> memblock_cap_memory_range() should come after memblock_add() etc as said
>>> in commit e888fa7bb882 ("memblock: Check memory add/cap ordering").
>>
>> void __init early_init_dt_scan_nodes(void)
>> {
>> //(1) -->early_init_dt_check_for_usable_mem_range, fill cap_mem_addr
>> rc = of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
>>
>> //(2) --> early_init_dt_add_memory_arch --> memblock_add()
>> of_scan_flat_dt(early_init_dt_scan_memory, NULL);
>>
>> //(3)
>> memblock_cap_memory_range(cap_mem_addr, cap_mem_size);
>> }
>>
>> I didn't get it. The above step (1),(2),(3) comply with
>> commit e888fa7bb882 ("memblock: Check memory add/cap ordering")
>>
> Well, at this scope, it does. But from a larger scope, let's say on
> arm64,
> setup_arch
> ...
> setup_machine_fdt(); //which holds your case
> ...
> efi_init(); //which call memblock_add, and breach the ordering.
>
>> Did you see the warning?
>> pr_warn("%s: No memory registered yet\n", __func__);
>>
> Yes, I did see this message, which brings me to commit e888fa7bb882
> ("memblock: Check memory add/cap ordering")
>
> I am also curious why this bug does not be discovered. Is CONFIG_EFI
> on at your case?
Yes, Both X86 and ARM64, CONFIG_EFI=y. I used the defconfig.
>
> Thanks,
>
> Pingfan
>>>
>>> As a consequence, the virtual address set up by copy_oldmem_page() does
>>> not bail out from the test of virt_addr_valid() in check_heap_object(),
>>> and finally hits the BUG_ON().
>>>
>>> Since memblock allocator has no idea about when the memblock is fully
>>> populated, while efi_init() is aware, so tackling this issue by calling the
>>> interface early_init_dt_check_for_usable_mem_range() exposed by of/fdt.
>>>
>>> Fixes: b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling")
>>> Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
>>> Cc: Rob Herring <robh+dt@kernel.org>
>>> Cc: Zhen Lei <thunder.leizhen@huawei.com>
>>> Cc: Catalin Marinas <catalin.marinas@arm.com>
>>> Cc: Will Deacon <will@kernel.org>
>>> Cc: Andrew Morton <akpm@linux-foundation.org>
>>> Cc: Mike Rapoport <rppt@kernel.org>
>>> Cc: Geert Uytterhoeven <geert+renesas@glider.be>
>>> Cc: Frank Rowand <frowand.list@gmail.com>
>>> Cc: Ard Biesheuvel <ardb@kernel.org>
>>> Cc: Nick Terrell <terrelln@fb.com>
>>> Cc: linux-arm-kernel@lists.infradead.org
>>> To: devicetree@vger.kernel.org
>>> To: linux-efi@vger.kernel.org
>>> ---
>>> v2 -> v3:
>>> use static inline stub to avoid #ifdef according to Rob's suggestion
>>>
>>> drivers/firmware/efi/efi-init.c | 5 +++++
>>> drivers/of/fdt.c | 2 +-
>>> include/linux/of_fdt.h | 2 ++
>>> 3 files changed, 8 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c
>>> index b19ce1a83f91..b2c829e95bd1 100644
>>> --- a/drivers/firmware/efi/efi-init.c
>>> +++ b/drivers/firmware/efi/efi-init.c
>>> @@ -235,6 +235,11 @@ void __init efi_init(void)
>>> }
>>>
>>> reserve_regions();
>>> + /*
>>> + * For memblock manipulation, the cap should come after the memblock_add().
>>> + * And now, memblock is fully populated, it is time to do capping.
>>> + */
>>> + early_init_dt_check_for_usable_mem_range();
>>> efi_esrt_init();
>>> efi_mokvar_table_init();
>>>
>>> diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
>>> index 18a2df431bfd..aa07ef5cab5f 100644
>>> --- a/drivers/of/fdt.c
>>> +++ b/drivers/of/fdt.c
>>> @@ -972,7 +972,7 @@ static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND;
>>> * location from flat tree
>>> * @node: reference to node containing usable memory range location ('chosen')
>>> */
>>> -static void __init early_init_dt_check_for_usable_mem_range(void)
>>> +void __init early_init_dt_check_for_usable_mem_range(void)
>>> {
>>> const __be32 *prop;
>>> int len;
>>> diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
>>> index cf48983d3c86..ad09beb6d13c 100644
>>> --- a/include/linux/of_fdt.h
>>> +++ b/include/linux/of_fdt.h
>>> @@ -62,6 +62,7 @@ extern int early_init_dt_scan_chosen(unsigned long node, const char *uname,
>>> int depth, void *data);
>>> extern int early_init_dt_scan_memory(unsigned long node, const char *uname,
>>> int depth, void *data);
>>> +extern void early_init_dt_check_for_usable_mem_range(void);
>>> extern int early_init_dt_scan_chosen_stdout(void);
>>> extern void early_init_fdt_scan_reserved_mem(void);
>>> extern void early_init_fdt_reserve_self(void);
>>> @@ -86,6 +87,7 @@ extern void unflatten_and_copy_device_tree(void);
>>> extern void early_init_devtree(void *);
>>> extern void early_get_first_memblock_info(void *, phys_addr_t *);
>>> #else /* CONFIG_OF_EARLY_FLATTREE */
>>> +static inline void early_init_dt_check_for_usable_mem_range(void) {}
>>> static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; }
>>> static inline void early_init_fdt_scan_reserved_mem(void) {}
>>> static inline void early_init_fdt_reserve_self(void) {}
>>>
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> linux-arm-kernel@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> .
>
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCHv3] efi: apply memblock cap after memblock_add()
2021-12-15 6:53 ` Leizhen (ThunderTown)
@ 2021-12-15 8:24 ` Pingfan Liu
2021-12-15 15:05 ` Rob Herring
1 sibling, 0 replies; 17+ messages in thread
From: Pingfan Liu @ 2021-12-15 8:24 UTC (permalink / raw)
To: Leizhen (ThunderTown)
Cc: devicetree, linux-efi, Rob Herring, Catalin Marinas, Will Deacon,
Andrew Morton, Mike Rapoport, Geert Uytterhoeven, Frank Rowand,
Ard Biesheuvel, Nick Terrell, linux-arm-kernel
On Wed, Dec 15, 2021 at 02:53:38PM +0800, Leizhen (ThunderTown) wrote:
>
>
> On 2021/12/15 13:29, Pingfan Liu wrote:
> > On Wed, Dec 15, 2021 at 11:58:03AM +0800, Leizhen (ThunderTown) wrote:
> >>
> >>
> >> On 2021/12/15 10:13, Pingfan Liu wrote:
> >>> On arm64, during kdump kernel saves vmcore, it runs into the following bug:
> >>> ...
> >>> [ 15.148919] usercopy: Kernel memory exposure attempt detected from SLUB object 'kmem_cache_node' (offset 0, size 4096)!
> >>> [ 15.159707] ------------[ cut here ]------------
> >>> [ 15.164311] kernel BUG at mm/usercopy.c:99!
> >>> [ 15.168482] Internal error: Oops - BUG: 0 [#1] SMP
> >>> [ 15.173261] Modules linked in: xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce sbsa_gwdt ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm_ttm_helper ttm drm nvme nvme_core xgene_hwmon i2c_designware_platform i2c_designware_core dm_mirror dm_region_hash dm_log dm_mod overlay squashfs zstd_decompress loop
> >>> [ 15.206186] CPU: 0 PID: 542 Comm: cp Not tainted 5.16.0-rc4 #1
> >>> [ 15.212006] Hardware name: GIGABYTE R272-P30-JG/MP32-AR0-JG, BIOS F12 (SCP: 1.5.20210426) 05/13/2021
> >>> [ 15.221125] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> >>> [ 15.228073] pc : usercopy_abort+0x9c/0xa0
> >>> [ 15.232074] lr : usercopy_abort+0x9c/0xa0
> >>> [ 15.236070] sp : ffff8000121abba0
> >>> [ 15.239371] x29: ffff8000121abbb0 x28: 0000000000003000 x27: 0000000000000000
> >>> [ 15.246494] x26: 0000000080000400 x25: 0000ffff885c7000 x24: 0000000000000000
> >>> [ 15.253617] x23: 000007ff80400000 x22: ffff07ff80401000 x21: 0000000000000001
> >>> [ 15.260739] x20: 0000000000001000 x19: ffff07ff80400000 x18: ffffffffffffffff
> >>> [ 15.267861] x17: 656a626f2042554c x16: 53206d6f72662064 x15: 6574636574656420
> >>> [ 15.274983] x14: 74706d6574746120 x13: 2129363930342065 x12: 7a6973202c302074
> >>> [ 15.282105] x11: ffffc8b041d1b148 x10: 00000000ffff8000 x9 : ffffc8b04012812c
> >>> [ 15.289228] x8 : 00000000ffff7fff x7 : ffffc8b041d1b148 x6 : 0000000000000000
> >>> [ 15.296349] x5 : 0000000000000000 x4 : 0000000000007fff x3 : 0000000000000000
> >>> [ 15.303471] x2 : 0000000000000000 x1 : ffff07ff8c064800 x0 : 000000000000006b
> >>> [ 15.310593] Call trace:
> >>> [ 15.313027] usercopy_abort+0x9c/0xa0
> >>> [ 15.316677] __check_heap_object+0xd4/0xf0
> >>> [ 15.320762] __check_object_size.part.0+0x160/0x1e0
> >>> [ 15.325628] __check_object_size+0x2c/0x40
> >>> [ 15.329711] copy_oldmem_page+0x7c/0x140
> >>> [ 15.333623] read_from_oldmem.part.0+0xfc/0x1c0
> >>> [ 15.338142] __read_vmcore.constprop.0+0x23c/0x350
> >>> [ 15.342920] read_vmcore+0x28/0x34
> >>> [ 15.346309] proc_reg_read+0xb4/0xf0
> >>> [ 15.349871] vfs_read+0xb8/0x1f0
> >>> [ 15.353088] ksys_read+0x74/0x100
> >>> [ 15.356390] __arm64_sys_read+0x28/0x34
> >>> ...
> >>>
> >>> This bug introduced by commit b261dba2fdb2 ("arm64: kdump: Remove custom
> >>> linux,usable-memory-range handling"), which moves
> >>> memblock_cap_memory_range() to fdt, but it breaches the rules that
> >>> memblock_cap_memory_range() should come after memblock_add() etc as said
> >>> in commit e888fa7bb882 ("memblock: Check memory add/cap ordering").
> >>
> >> void __init early_init_dt_scan_nodes(void)
> >> {
> >> //(1) -->early_init_dt_check_for_usable_mem_range, fill cap_mem_addr
> >> rc = of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
> >>
> >> //(2) --> early_init_dt_add_memory_arch --> memblock_add()
> >> of_scan_flat_dt(early_init_dt_scan_memory, NULL);
> >>
> >> //(3)
> >> memblock_cap_memory_range(cap_mem_addr, cap_mem_size);
> >> }
> >>
> >> I didn't get it. The above step (1),(2),(3) comply with
> >> commit e888fa7bb882 ("memblock: Check memory add/cap ordering")
> >>
> > Well, at this scope, it does. But from a larger scope, let's say on
> > arm64,
> > setup_arch
> > ...
> > setup_machine_fdt(); //which holds your case
> > ...
> > efi_init(); //which call memblock_add, and breach the ordering.
> >
> >> Did you see the warning?
> >> pr_warn("%s: No memory registered yet\n", __func__);
> >>
> > Yes, I did see this message, which brings me to commit e888fa7bb882
> > ("memblock: Check memory add/cap ordering")
> >
> > I am also curious why this bug does not be discovered. Is CONFIG_EFI
> > on at your case?
>
> Yes, Both X86 and ARM64, CONFIG_EFI=y. I used the defconfig.
>
Maybe due to different md?
Because
efi_init()->reserve_regions()->early_init_dt_add_memory_arch()->memblock_add()
on arm64, if is_memory(md). This is the path breaching the rule during
my test.
Thanks
Pingfan
> >
> > Thanks,
> >
> > Pingfan
> >>>
> >>> As a consequence, the virtual address set up by copy_oldmem_page() does
> >>> not bail out from the test of virt_addr_valid() in check_heap_object(),
> >>> and finally hits the BUG_ON().
> >>>
> >>> Since memblock allocator has no idea about when the memblock is fully
> >>> populated, while efi_init() is aware, so tackling this issue by calling the
> >>> interface early_init_dt_check_for_usable_mem_range() exposed by of/fdt.
> >>>
> >>> Fixes: b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling")
> >>> Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
> >>> Cc: Rob Herring <robh+dt@kernel.org>
> >>> Cc: Zhen Lei <thunder.leizhen@huawei.com>
> >>> Cc: Catalin Marinas <catalin.marinas@arm.com>
> >>> Cc: Will Deacon <will@kernel.org>
> >>> Cc: Andrew Morton <akpm@linux-foundation.org>
> >>> Cc: Mike Rapoport <rppt@kernel.org>
> >>> Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> >>> Cc: Frank Rowand <frowand.list@gmail.com>
> >>> Cc: Ard Biesheuvel <ardb@kernel.org>
> >>> Cc: Nick Terrell <terrelln@fb.com>
> >>> Cc: linux-arm-kernel@lists.infradead.org
> >>> To: devicetree@vger.kernel.org
> >>> To: linux-efi@vger.kernel.org
> >>> ---
> >>> v2 -> v3:
> >>> use static inline stub to avoid #ifdef according to Rob's suggestion
> >>>
> >>> drivers/firmware/efi/efi-init.c | 5 +++++
> >>> drivers/of/fdt.c | 2 +-
> >>> include/linux/of_fdt.h | 2 ++
> >>> 3 files changed, 8 insertions(+), 1 deletion(-)
> >>>
> >>> diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c
> >>> index b19ce1a83f91..b2c829e95bd1 100644
> >>> --- a/drivers/firmware/efi/efi-init.c
> >>> +++ b/drivers/firmware/efi/efi-init.c
> >>> @@ -235,6 +235,11 @@ void __init efi_init(void)
> >>> }
> >>>
> >>> reserve_regions();
> >>> + /*
> >>> + * For memblock manipulation, the cap should come after the memblock_add().
> >>> + * And now, memblock is fully populated, it is time to do capping.
> >>> + */
> >>> + early_init_dt_check_for_usable_mem_range();
> >>> efi_esrt_init();
> >>> efi_mokvar_table_init();
> >>>
> >>> diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
> >>> index 18a2df431bfd..aa07ef5cab5f 100644
> >>> --- a/drivers/of/fdt.c
> >>> +++ b/drivers/of/fdt.c
> >>> @@ -972,7 +972,7 @@ static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND;
> >>> * location from flat tree
> >>> * @node: reference to node containing usable memory range location ('chosen')
> >>> */
> >>> -static void __init early_init_dt_check_for_usable_mem_range(void)
> >>> +void __init early_init_dt_check_for_usable_mem_range(void)
> >>> {
> >>> const __be32 *prop;
> >>> int len;
> >>> diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
> >>> index cf48983d3c86..ad09beb6d13c 100644
> >>> --- a/include/linux/of_fdt.h
> >>> +++ b/include/linux/of_fdt.h
> >>> @@ -62,6 +62,7 @@ extern int early_init_dt_scan_chosen(unsigned long node, const char *uname,
> >>> int depth, void *data);
> >>> extern int early_init_dt_scan_memory(unsigned long node, const char *uname,
> >>> int depth, void *data);
> >>> +extern void early_init_dt_check_for_usable_mem_range(void);
> >>> extern int early_init_dt_scan_chosen_stdout(void);
> >>> extern void early_init_fdt_scan_reserved_mem(void);
> >>> extern void early_init_fdt_reserve_self(void);
> >>> @@ -86,6 +87,7 @@ extern void unflatten_and_copy_device_tree(void);
> >>> extern void early_init_devtree(void *);
> >>> extern void early_get_first_memblock_info(void *, phys_addr_t *);
> >>> #else /* CONFIG_OF_EARLY_FLATTREE */
> >>> +static inline void early_init_dt_check_for_usable_mem_range(void) {}
> >>> static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; }
> >>> static inline void early_init_fdt_scan_reserved_mem(void) {}
> >>> static inline void early_init_fdt_reserve_self(void) {}
> >>>
> >>
> >> _______________________________________________
> >> linux-arm-kernel mailing list
> >> linux-arm-kernel@lists.infradead.org
> >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> > .
> >
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCHv3] efi: apply memblock cap after memblock_add()
2021-12-15 6:53 ` Leizhen (ThunderTown)
2021-12-15 8:24 ` Pingfan Liu
@ 2021-12-15 15:05 ` Rob Herring
2021-12-16 13:34 ` Leizhen (ThunderTown)
1 sibling, 1 reply; 17+ messages in thread
From: Rob Herring @ 2021-12-15 15:05 UTC (permalink / raw)
To: Leizhen (ThunderTown)
Cc: Pingfan Liu, devicetree, linux-efi, Catalin Marinas, Will Deacon,
Andrew Morton, Mike Rapoport, Geert Uytterhoeven, Frank Rowand,
Ard Biesheuvel, Nick Terrell, linux-arm-kernel
On Wed, Dec 15, 2021 at 12:53 AM Leizhen (ThunderTown)
<thunder.leizhen@huawei.com> wrote:
>
>
>
> On 2021/12/15 13:29, Pingfan Liu wrote:
> > On Wed, Dec 15, 2021 at 11:58:03AM +0800, Leizhen (ThunderTown) wrote:
> >>
> >>
> >> On 2021/12/15 10:13, Pingfan Liu wrote:
> >>> On arm64, during kdump kernel saves vmcore, it runs into the following bug:
> >>> ...
> >>> [ 15.148919] usercopy: Kernel memory exposure attempt detected from SLUB object 'kmem_cache_node' (offset 0, size 4096)!
> >>> [ 15.159707] ------------[ cut here ]------------
> >>> [ 15.164311] kernel BUG at mm/usercopy.c:99!
> >>> [ 15.168482] Internal error: Oops - BUG: 0 [#1] SMP
> >>> [ 15.173261] Modules linked in: xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce sbsa_gwdt ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm_ttm_helper ttm drm nvme nvme_core xgene_hwmon i2c_designware_platform i2c_designware_core dm_mirror dm_region_hash dm_log dm_mod overlay squashfs zstd_decompress loop
> >>> [ 15.206186] CPU: 0 PID: 542 Comm: cp Not tainted 5.16.0-rc4 #1
> >>> [ 15.212006] Hardware name: GIGABYTE R272-P30-JG/MP32-AR0-JG, BIOS F12 (SCP: 1.5.20210426) 05/13/2021
> >>> [ 15.221125] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> >>> [ 15.228073] pc : usercopy_abort+0x9c/0xa0
> >>> [ 15.232074] lr : usercopy_abort+0x9c/0xa0
> >>> [ 15.236070] sp : ffff8000121abba0
> >>> [ 15.239371] x29: ffff8000121abbb0 x28: 0000000000003000 x27: 0000000000000000
> >>> [ 15.246494] x26: 0000000080000400 x25: 0000ffff885c7000 x24: 0000000000000000
> >>> [ 15.253617] x23: 000007ff80400000 x22: ffff07ff80401000 x21: 0000000000000001
> >>> [ 15.260739] x20: 0000000000001000 x19: ffff07ff80400000 x18: ffffffffffffffff
> >>> [ 15.267861] x17: 656a626f2042554c x16: 53206d6f72662064 x15: 6574636574656420
> >>> [ 15.274983] x14: 74706d6574746120 x13: 2129363930342065 x12: 7a6973202c302074
> >>> [ 15.282105] x11: ffffc8b041d1b148 x10: 00000000ffff8000 x9 : ffffc8b04012812c
> >>> [ 15.289228] x8 : 00000000ffff7fff x7 : ffffc8b041d1b148 x6 : 0000000000000000
> >>> [ 15.296349] x5 : 0000000000000000 x4 : 0000000000007fff x3 : 0000000000000000
> >>> [ 15.303471] x2 : 0000000000000000 x1 : ffff07ff8c064800 x0 : 000000000000006b
> >>> [ 15.310593] Call trace:
> >>> [ 15.313027] usercopy_abort+0x9c/0xa0
> >>> [ 15.316677] __check_heap_object+0xd4/0xf0
> >>> [ 15.320762] __check_object_size.part.0+0x160/0x1e0
> >>> [ 15.325628] __check_object_size+0x2c/0x40
> >>> [ 15.329711] copy_oldmem_page+0x7c/0x140
> >>> [ 15.333623] read_from_oldmem.part.0+0xfc/0x1c0
> >>> [ 15.338142] __read_vmcore.constprop.0+0x23c/0x350
> >>> [ 15.342920] read_vmcore+0x28/0x34
> >>> [ 15.346309] proc_reg_read+0xb4/0xf0
> >>> [ 15.349871] vfs_read+0xb8/0x1f0
> >>> [ 15.353088] ksys_read+0x74/0x100
> >>> [ 15.356390] __arm64_sys_read+0x28/0x34
> >>> ...
> >>>
> >>> This bug introduced by commit b261dba2fdb2 ("arm64: kdump: Remove custom
> >>> linux,usable-memory-range handling"), which moves
> >>> memblock_cap_memory_range() to fdt, but it breaches the rules that
> >>> memblock_cap_memory_range() should come after memblock_add() etc as said
> >>> in commit e888fa7bb882 ("memblock: Check memory add/cap ordering").
> >>
> >> void __init early_init_dt_scan_nodes(void)
> >> {
> >> //(1) -->early_init_dt_check_for_usable_mem_range, fill cap_mem_addr
> >> rc = of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
> >>
> >> //(2) --> early_init_dt_add_memory_arch --> memblock_add()
> >> of_scan_flat_dt(early_init_dt_scan_memory, NULL);
> >>
> >> //(3)
> >> memblock_cap_memory_range(cap_mem_addr, cap_mem_size);
> >> }
> >>
> >> I didn't get it. The above step (1),(2),(3) comply with
> >> commit e888fa7bb882 ("memblock: Check memory add/cap ordering")
> >>
> > Well, at this scope, it does. But from a larger scope, let's say on
> > arm64,
> > setup_arch
> > ...
> > setup_machine_fdt(); //which holds your case
> > ...
> > efi_init(); //which call memblock_add, and breach the ordering.
> >
> >> Did you see the warning?
> >> pr_warn("%s: No memory registered yet\n", __func__);
> >>
> > Yes, I did see this message, which brings me to commit e888fa7bb882
> > ("memblock: Check memory add/cap ordering")
> >
> > I am also curious why this bug does not be discovered. Is CONFIG_EFI
> > on at your case?
>
> Yes, Both X86 and ARM64, CONFIG_EFI=y. I used the defconfig.
Are you booting using EFI though? efi_init() removes all memblocks
that may have been setup from the DT and adds memblocks using the EFI
memory map information.
Rob
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCHv3] efi: apply memblock cap after memblock_add()
2021-12-15 15:05 ` Rob Herring
@ 2021-12-16 13:34 ` Leizhen (ThunderTown)
0 siblings, 0 replies; 17+ messages in thread
From: Leizhen (ThunderTown) @ 2021-12-16 13:34 UTC (permalink / raw)
To: Rob Herring
Cc: Pingfan Liu, devicetree, linux-efi, Catalin Marinas, Will Deacon,
Andrew Morton, Mike Rapoport, Geert Uytterhoeven, Frank Rowand,
Ard Biesheuvel, Nick Terrell, linux-arm-kernel
On 2021/12/15 23:05, Rob Herring wrote:
> On Wed, Dec 15, 2021 at 12:53 AM Leizhen (ThunderTown)
> <thunder.leizhen@huawei.com> wrote:
>>
>>
>>
>> On 2021/12/15 13:29, Pingfan Liu wrote:
>>> On Wed, Dec 15, 2021 at 11:58:03AM +0800, Leizhen (ThunderTown) wrote:
>>>>
>>>>
>>>> On 2021/12/15 10:13, Pingfan Liu wrote:
>>>>> On arm64, during kdump kernel saves vmcore, it runs into the following bug:
>>>>> ...
>>>>> [ 15.148919] usercopy: Kernel memory exposure attempt detected from SLUB object 'kmem_cache_node' (offset 0, size 4096)!
>>>>> [ 15.159707] ------------[ cut here ]------------
>>>>> [ 15.164311] kernel BUG at mm/usercopy.c:99!
>>>>> [ 15.168482] Internal error: Oops - BUG: 0 [#1] SMP
>>>>> [ 15.173261] Modules linked in: xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce sbsa_gwdt ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm_ttm_helper ttm drm nvme nvme_core xgene_hwmon i2c_designware_platform i2c_designware_core dm_mirror dm_region_hash dm_log dm_mod overlay squashfs zstd_decompress loop
>>>>> [ 15.206186] CPU: 0 PID: 542 Comm: cp Not tainted 5.16.0-rc4 #1
>>>>> [ 15.212006] Hardware name: GIGABYTE R272-P30-JG/MP32-AR0-JG, BIOS F12 (SCP: 1.5.20210426) 05/13/2021
>>>>> [ 15.221125] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
>>>>> [ 15.228073] pc : usercopy_abort+0x9c/0xa0
>>>>> [ 15.232074] lr : usercopy_abort+0x9c/0xa0
>>>>> [ 15.236070] sp : ffff8000121abba0
>>>>> [ 15.239371] x29: ffff8000121abbb0 x28: 0000000000003000 x27: 0000000000000000
>>>>> [ 15.246494] x26: 0000000080000400 x25: 0000ffff885c7000 x24: 0000000000000000
>>>>> [ 15.253617] x23: 000007ff80400000 x22: ffff07ff80401000 x21: 0000000000000001
>>>>> [ 15.260739] x20: 0000000000001000 x19: ffff07ff80400000 x18: ffffffffffffffff
>>>>> [ 15.267861] x17: 656a626f2042554c x16: 53206d6f72662064 x15: 6574636574656420
>>>>> [ 15.274983] x14: 74706d6574746120 x13: 2129363930342065 x12: 7a6973202c302074
>>>>> [ 15.282105] x11: ffffc8b041d1b148 x10: 00000000ffff8000 x9 : ffffc8b04012812c
>>>>> [ 15.289228] x8 : 00000000ffff7fff x7 : ffffc8b041d1b148 x6 : 0000000000000000
>>>>> [ 15.296349] x5 : 0000000000000000 x4 : 0000000000007fff x3 : 0000000000000000
>>>>> [ 15.303471] x2 : 0000000000000000 x1 : ffff07ff8c064800 x0 : 000000000000006b
>>>>> [ 15.310593] Call trace:
>>>>> [ 15.313027] usercopy_abort+0x9c/0xa0
>>>>> [ 15.316677] __check_heap_object+0xd4/0xf0
>>>>> [ 15.320762] __check_object_size.part.0+0x160/0x1e0
>>>>> [ 15.325628] __check_object_size+0x2c/0x40
>>>>> [ 15.329711] copy_oldmem_page+0x7c/0x140
>>>>> [ 15.333623] read_from_oldmem.part.0+0xfc/0x1c0
>>>>> [ 15.338142] __read_vmcore.constprop.0+0x23c/0x350
>>>>> [ 15.342920] read_vmcore+0x28/0x34
>>>>> [ 15.346309] proc_reg_read+0xb4/0xf0
>>>>> [ 15.349871] vfs_read+0xb8/0x1f0
>>>>> [ 15.353088] ksys_read+0x74/0x100
>>>>> [ 15.356390] __arm64_sys_read+0x28/0x34
>>>>> ...
>>>>>
>>>>> This bug introduced by commit b261dba2fdb2 ("arm64: kdump: Remove custom
>>>>> linux,usable-memory-range handling"), which moves
>>>>> memblock_cap_memory_range() to fdt, but it breaches the rules that
>>>>> memblock_cap_memory_range() should come after memblock_add() etc as said
>>>>> in commit e888fa7bb882 ("memblock: Check memory add/cap ordering").
>>>>
>>>> void __init early_init_dt_scan_nodes(void)
>>>> {
>>>> //(1) -->early_init_dt_check_for_usable_mem_range, fill cap_mem_addr
>>>> rc = of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
>>>>
>>>> //(2) --> early_init_dt_add_memory_arch --> memblock_add()
>>>> of_scan_flat_dt(early_init_dt_scan_memory, NULL);
>>>>
>>>> //(3)
>>>> memblock_cap_memory_range(cap_mem_addr, cap_mem_size);
>>>> }
>>>>
>>>> I didn't get it. The above step (1),(2),(3) comply with
>>>> commit e888fa7bb882 ("memblock: Check memory add/cap ordering")
>>>>
>>> Well, at this scope, it does. But from a larger scope, let's say on
>>> arm64,
>>> setup_arch
>>> ...
>>> setup_machine_fdt(); //which holds your case
>>> ...
>>> efi_init(); //which call memblock_add, and breach the ordering.
>>>
>>>> Did you see the warning?
>>>> pr_warn("%s: No memory registered yet\n", __func__);
>>>>
>>> Yes, I did see this message, which brings me to commit e888fa7bb882
>>> ("memblock: Check memory add/cap ordering")
>>>
>>> I am also curious why this bug does not be discovered. Is CONFIG_EFI
>>> on at your case?
>>
>> Yes, Both X86 and ARM64, CONFIG_EFI=y. I used the defconfig.
>
> Are you booting using EFI though? efi_init() removes all memblocks
> that may have been setup from the DT and adds memblocks using the EFI
> memory map information.
Sorry, I tested it with QEMU. I checked that efi_system_table is not exist.
>
> Rob
> .
>
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCHv3] efi: apply memblock cap after memblock_add()
2021-12-15 2:13 ` [PATCHv3] " Pingfan Liu
2021-12-15 3:58 ` Leizhen (ThunderTown)
@ 2021-12-17 15:08 ` Rob Herring
2021-12-17 15:25 ` Ard Biesheuvel
2021-12-21 15:17 ` Rob Herring
2021-12-22 8:00 ` Leizhen (ThunderTown)
3 siblings, 1 reply; 17+ messages in thread
From: Rob Herring @ 2021-12-17 15:08 UTC (permalink / raw)
To: Pingfan Liu, Ard Biesheuvel
Cc: devicetree, linux-efi, Zhen Lei, Catalin Marinas, Will Deacon,
Andrew Morton, Mike Rapoport, Geert Uytterhoeven, Frank Rowand,
Nick Terrell, linux-arm-kernel
On Tue, Dec 14, 2021 at 8:14 PM Pingfan Liu <kernelfans@gmail.com> wrote:
>
> On arm64, during kdump kernel saves vmcore, it runs into the following bug:
> ...
> [ 15.148919] usercopy: Kernel memory exposure attempt detected from SLUB object 'kmem_cache_node' (offset 0, size 4096)!
> [ 15.159707] ------------[ cut here ]------------
> [ 15.164311] kernel BUG at mm/usercopy.c:99!
> [ 15.168482] Internal error: Oops - BUG: 0 [#1] SMP
> [ 15.173261] Modules linked in: xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce sbsa_gwdt ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm_ttm_helper ttm drm nvme nvme_core xgene_hwmon i2c_designware_platform i2c_designware_core dm_mirror dm_region_hash dm_log dm_mod overlay squashfs zstd_decompress loop
> [ 15.206186] CPU: 0 PID: 542 Comm: cp Not tainted 5.16.0-rc4 #1
> [ 15.212006] Hardware name: GIGABYTE R272-P30-JG/MP32-AR0-JG, BIOS F12 (SCP: 1.5.20210426) 05/13/2021
> [ 15.221125] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> [ 15.228073] pc : usercopy_abort+0x9c/0xa0
> [ 15.232074] lr : usercopy_abort+0x9c/0xa0
> [ 15.236070] sp : ffff8000121abba0
> [ 15.239371] x29: ffff8000121abbb0 x28: 0000000000003000 x27: 0000000000000000
> [ 15.246494] x26: 0000000080000400 x25: 0000ffff885c7000 x24: 0000000000000000
> [ 15.253617] x23: 000007ff80400000 x22: ffff07ff80401000 x21: 0000000000000001
> [ 15.260739] x20: 0000000000001000 x19: ffff07ff80400000 x18: ffffffffffffffff
> [ 15.267861] x17: 656a626f2042554c x16: 53206d6f72662064 x15: 6574636574656420
> [ 15.274983] x14: 74706d6574746120 x13: 2129363930342065 x12: 7a6973202c302074
> [ 15.282105] x11: ffffc8b041d1b148 x10: 00000000ffff8000 x9 : ffffc8b04012812c
> [ 15.289228] x8 : 00000000ffff7fff x7 : ffffc8b041d1b148 x6 : 0000000000000000
> [ 15.296349] x5 : 0000000000000000 x4 : 0000000000007fff x3 : 0000000000000000
> [ 15.303471] x2 : 0000000000000000 x1 : ffff07ff8c064800 x0 : 000000000000006b
> [ 15.310593] Call trace:
> [ 15.313027] usercopy_abort+0x9c/0xa0
> [ 15.316677] __check_heap_object+0xd4/0xf0
> [ 15.320762] __check_object_size.part.0+0x160/0x1e0
> [ 15.325628] __check_object_size+0x2c/0x40
> [ 15.329711] copy_oldmem_page+0x7c/0x140
> [ 15.333623] read_from_oldmem.part.0+0xfc/0x1c0
> [ 15.338142] __read_vmcore.constprop.0+0x23c/0x350
> [ 15.342920] read_vmcore+0x28/0x34
> [ 15.346309] proc_reg_read+0xb4/0xf0
> [ 15.349871] vfs_read+0xb8/0x1f0
> [ 15.353088] ksys_read+0x74/0x100
> [ 15.356390] __arm64_sys_read+0x28/0x34
> ...
>
> This bug introduced by commit b261dba2fdb2 ("arm64: kdump: Remove custom
> linux,usable-memory-range handling"), which moves
> memblock_cap_memory_range() to fdt, but it breaches the rules that
> memblock_cap_memory_range() should come after memblock_add() etc as said
> in commit e888fa7bb882 ("memblock: Check memory add/cap ordering").
>
> As a consequence, the virtual address set up by copy_oldmem_page() does
> not bail out from the test of virt_addr_valid() in check_heap_object(),
> and finally hits the BUG_ON().
>
> Since memblock allocator has no idea about when the memblock is fully
> populated, while efi_init() is aware, so tackling this issue by calling the
> interface early_init_dt_check_for_usable_mem_range() exposed by of/fdt.
>
> Fixes: b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling")
> Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Zhen Lei <thunder.leizhen@huawei.com>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will@kernel.org>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Mike Rapoport <rppt@kernel.org>
> Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> Cc: Frank Rowand <frowand.list@gmail.com>
> Cc: Ard Biesheuvel <ardb@kernel.org>
> Cc: Nick Terrell <terrelln@fb.com>
> Cc: linux-arm-kernel@lists.infradead.org
> To: devicetree@vger.kernel.org
> To: linux-efi@vger.kernel.org
> ---
> v2 -> v3:
> use static inline stub to avoid #ifdef according to Rob's suggestion
>
> drivers/firmware/efi/efi-init.c | 5 +++++
> drivers/of/fdt.c | 2 +-
> include/linux/of_fdt.h | 2 ++
> 3 files changed, 8 insertions(+), 1 deletion(-)
Looks good to me. I'll apply and send to Linus once the EFI folks ack this.
Rob
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCHv3] efi: apply memblock cap after memblock_add()
2021-12-17 15:08 ` Rob Herring
@ 2021-12-17 15:25 ` Ard Biesheuvel
0 siblings, 0 replies; 17+ messages in thread
From: Ard Biesheuvel @ 2021-12-17 15:25 UTC (permalink / raw)
To: Rob Herring
Cc: Pingfan Liu,
open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
linux-efi, Zhen Lei, Catalin Marinas, Will Deacon, Andrew Morton,
Mike Rapoport, Geert Uytterhoeven, Frank Rowand, Nick Terrell,
linux-arm-kernel
On Fri, 17 Dec 2021 at 16:08, Rob Herring <robh+dt@kernel.org> wrote:
>
> On Tue, Dec 14, 2021 at 8:14 PM Pingfan Liu <kernelfans@gmail.com> wrote:
> >
> > On arm64, during kdump kernel saves vmcore, it runs into the following bug:
> > ...
> > [ 15.148919] usercopy: Kernel memory exposure attempt detected from SLUB object 'kmem_cache_node' (offset 0, size 4096)!
> > [ 15.159707] ------------[ cut here ]------------
> > [ 15.164311] kernel BUG at mm/usercopy.c:99!
> > [ 15.168482] Internal error: Oops - BUG: 0 [#1] SMP
> > [ 15.173261] Modules linked in: xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce sbsa_gwdt ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm_ttm_helper ttm drm nvme nvme_core xgene_hwmon i2c_designware_platform i2c_designware_core dm_mirror dm_region_hash dm_log dm_mod overlay squashfs zstd_decompress loop
> > [ 15.206186] CPU: 0 PID: 542 Comm: cp Not tainted 5.16.0-rc4 #1
> > [ 15.212006] Hardware name: GIGABYTE R272-P30-JG/MP32-AR0-JG, BIOS F12 (SCP: 1.5.20210426) 05/13/2021
> > [ 15.221125] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> > [ 15.228073] pc : usercopy_abort+0x9c/0xa0
> > [ 15.232074] lr : usercopy_abort+0x9c/0xa0
> > [ 15.236070] sp : ffff8000121abba0
> > [ 15.239371] x29: ffff8000121abbb0 x28: 0000000000003000 x27: 0000000000000000
> > [ 15.246494] x26: 0000000080000400 x25: 0000ffff885c7000 x24: 0000000000000000
> > [ 15.253617] x23: 000007ff80400000 x22: ffff07ff80401000 x21: 0000000000000001
> > [ 15.260739] x20: 0000000000001000 x19: ffff07ff80400000 x18: ffffffffffffffff
> > [ 15.267861] x17: 656a626f2042554c x16: 53206d6f72662064 x15: 6574636574656420
> > [ 15.274983] x14: 74706d6574746120 x13: 2129363930342065 x12: 7a6973202c302074
> > [ 15.282105] x11: ffffc8b041d1b148 x10: 00000000ffff8000 x9 : ffffc8b04012812c
> > [ 15.289228] x8 : 00000000ffff7fff x7 : ffffc8b041d1b148 x6 : 0000000000000000
> > [ 15.296349] x5 : 0000000000000000 x4 : 0000000000007fff x3 : 0000000000000000
> > [ 15.303471] x2 : 0000000000000000 x1 : ffff07ff8c064800 x0 : 000000000000006b
> > [ 15.310593] Call trace:
> > [ 15.313027] usercopy_abort+0x9c/0xa0
> > [ 15.316677] __check_heap_object+0xd4/0xf0
> > [ 15.320762] __check_object_size.part.0+0x160/0x1e0
> > [ 15.325628] __check_object_size+0x2c/0x40
> > [ 15.329711] copy_oldmem_page+0x7c/0x140
> > [ 15.333623] read_from_oldmem.part.0+0xfc/0x1c0
> > [ 15.338142] __read_vmcore.constprop.0+0x23c/0x350
> > [ 15.342920] read_vmcore+0x28/0x34
> > [ 15.346309] proc_reg_read+0xb4/0xf0
> > [ 15.349871] vfs_read+0xb8/0x1f0
> > [ 15.353088] ksys_read+0x74/0x100
> > [ 15.356390] __arm64_sys_read+0x28/0x34
> > ...
> >
> > This bug introduced by commit b261dba2fdb2 ("arm64: kdump: Remove custom
> > linux,usable-memory-range handling"), which moves
> > memblock_cap_memory_range() to fdt, but it breaches the rules that
> > memblock_cap_memory_range() should come after memblock_add() etc as said
> > in commit e888fa7bb882 ("memblock: Check memory add/cap ordering").
> >
> > As a consequence, the virtual address set up by copy_oldmem_page() does
> > not bail out from the test of virt_addr_valid() in check_heap_object(),
> > and finally hits the BUG_ON().
> >
> > Since memblock allocator has no idea about when the memblock is fully
> > populated, while efi_init() is aware, so tackling this issue by calling the
> > interface early_init_dt_check_for_usable_mem_range() exposed by of/fdt.
> >
> > Fixes: b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling")
> > Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
> > Cc: Rob Herring <robh+dt@kernel.org>
> > Cc: Zhen Lei <thunder.leizhen@huawei.com>
> > Cc: Catalin Marinas <catalin.marinas@arm.com>
> > Cc: Will Deacon <will@kernel.org>
> > Cc: Andrew Morton <akpm@linux-foundation.org>
> > Cc: Mike Rapoport <rppt@kernel.org>
> > Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> > Cc: Frank Rowand <frowand.list@gmail.com>
> > Cc: Ard Biesheuvel <ardb@kernel.org>
> > Cc: Nick Terrell <terrelln@fb.com>
> > Cc: linux-arm-kernel@lists.infradead.org
> > To: devicetree@vger.kernel.org
> > To: linux-efi@vger.kernel.org
> > ---
> > v2 -> v3:
> > use static inline stub to avoid #ifdef according to Rob's suggestion
> >
> > drivers/firmware/efi/efi-init.c | 5 +++++
> > drivers/of/fdt.c | 2 +-
> > include/linux/of_fdt.h | 2 ++
> > 3 files changed, 8 insertions(+), 1 deletion(-)
>
> Looks good to me. I'll apply and send to Linus once the EFI folks ack this.
>
Where needed in the series,
Acked-by: Ard Biesheuvel <ardb@kernel.org>
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCHv3] efi: apply memblock cap after memblock_add()
2021-12-15 2:13 ` [PATCHv3] " Pingfan Liu
2021-12-15 3:58 ` Leizhen (ThunderTown)
2021-12-17 15:08 ` Rob Herring
@ 2021-12-21 15:17 ` Rob Herring
2021-12-22 8:00 ` Leizhen (ThunderTown)
3 siblings, 0 replies; 17+ messages in thread
From: Rob Herring @ 2021-12-21 15:17 UTC (permalink / raw)
To: Pingfan Liu
Cc: Will Deacon, Mike Rapoport, Ard Biesheuvel, Nick Terrell,
Frank Rowand, devicetree, linux-efi, Geert Uytterhoeven,
Andrew Morton, Catalin Marinas, Rob Herring, linux-arm-kernel,
Zhen Lei
On Wed, 15 Dec 2021 10:13:48 +0800, Pingfan Liu wrote:
> On arm64, during kdump kernel saves vmcore, it runs into the following bug:
> ...
> [ 15.148919] usercopy: Kernel memory exposure attempt detected from SLUB object 'kmem_cache_node' (offset 0, size 4096)!
> [ 15.159707] ------------[ cut here ]------------
> [ 15.164311] kernel BUG at mm/usercopy.c:99!
> [ 15.168482] Internal error: Oops - BUG: 0 [#1] SMP
> [ 15.173261] Modules linked in: xfs libcrc32c crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce sbsa_gwdt ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm_ttm_helper ttm drm nvme nvme_core xgene_hwmon i2c_designware_platform i2c_designware_core dm_mirror dm_region_hash dm_log dm_mod overlay squashfs zstd_decompress loop
> [ 15.206186] CPU: 0 PID: 542 Comm: cp Not tainted 5.16.0-rc4 #1
> [ 15.212006] Hardware name: GIGABYTE R272-P30-JG/MP32-AR0-JG, BIOS F12 (SCP: 1.5.20210426) 05/13/2021
> [ 15.221125] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> [ 15.228073] pc : usercopy_abort+0x9c/0xa0
> [ 15.232074] lr : usercopy_abort+0x9c/0xa0
> [ 15.236070] sp : ffff8000121abba0
> [ 15.239371] x29: ffff8000121abbb0 x28: 0000000000003000 x27: 0000000000000000
> [ 15.246494] x26: 0000000080000400 x25: 0000ffff885c7000 x24: 0000000000000000
> [ 15.253617] x23: 000007ff80400000 x22: ffff07ff80401000 x21: 0000000000000001
> [ 15.260739] x20: 0000000000001000 x19: ffff07ff80400000 x18: ffffffffffffffff
> [ 15.267861] x17: 656a626f2042554c x16: 53206d6f72662064 x15: 6574636574656420
> [ 15.274983] x14: 74706d6574746120 x13: 2129363930342065 x12: 7a6973202c302074
> [ 15.282105] x11: ffffc8b041d1b148 x10: 00000000ffff8000 x9 : ffffc8b04012812c
> [ 15.289228] x8 : 00000000ffff7fff x7 : ffffc8b041d1b148 x6 : 0000000000000000
> [ 15.296349] x5 : 0000000000000000 x4 : 0000000000007fff x3 : 0000000000000000
> [ 15.303471] x2 : 0000000000000000 x1 : ffff07ff8c064800 x0 : 000000000000006b
> [ 15.310593] Call trace:
> [ 15.313027] usercopy_abort+0x9c/0xa0
> [ 15.316677] __check_heap_object+0xd4/0xf0
> [ 15.320762] __check_object_size.part.0+0x160/0x1e0
> [ 15.325628] __check_object_size+0x2c/0x40
> [ 15.329711] copy_oldmem_page+0x7c/0x140
> [ 15.333623] read_from_oldmem.part.0+0xfc/0x1c0
> [ 15.338142] __read_vmcore.constprop.0+0x23c/0x350
> [ 15.342920] read_vmcore+0x28/0x34
> [ 15.346309] proc_reg_read+0xb4/0xf0
> [ 15.349871] vfs_read+0xb8/0x1f0
> [ 15.353088] ksys_read+0x74/0x100
> [ 15.356390] __arm64_sys_read+0x28/0x34
> ...
>
> This bug introduced by commit b261dba2fdb2 ("arm64: kdump: Remove custom
> linux,usable-memory-range handling"), which moves
> memblock_cap_memory_range() to fdt, but it breaches the rules that
> memblock_cap_memory_range() should come after memblock_add() etc as said
> in commit e888fa7bb882 ("memblock: Check memory add/cap ordering").
>
> As a consequence, the virtual address set up by copy_oldmem_page() does
> not bail out from the test of virt_addr_valid() in check_heap_object(),
> and finally hits the BUG_ON().
>
> Since memblock allocator has no idea about when the memblock is fully
> populated, while efi_init() is aware, so tackling this issue by calling the
> interface early_init_dt_check_for_usable_mem_range() exposed by of/fdt.
>
> Fixes: b261dba2fdb2 ("arm64: kdump: Remove custom linux,usable-memory-range handling")
> Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Zhen Lei <thunder.leizhen@huawei.com>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will@kernel.org>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Mike Rapoport <rppt@kernel.org>
> Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> Cc: Frank Rowand <frowand.list@gmail.com>
> Cc: Ard Biesheuvel <ardb@kernel.org>
> Cc: Nick Terrell <terrelln@fb.com>
> Cc: linux-arm-kernel@lists.infradead.org
> To: devicetree@vger.kernel.org
> To: linux-efi@vger.kernel.org
> ---
> v2 -> v3:
> use static inline stub to avoid #ifdef according to Rob's suggestion
>
> drivers/firmware/efi/efi-init.c | 5 +++++
> drivers/of/fdt.c | 2 +-
> include/linux/of_fdt.h | 2 ++
> 3 files changed, 8 insertions(+), 1 deletion(-)
>
Applied, thanks!
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCHv3] efi: apply memblock cap after memblock_add()
2021-12-15 2:13 ` [PATCHv3] " Pingfan Liu
` (2 preceding siblings ...)
2021-12-21 15:17 ` Rob Herring
@ 2021-12-22 8:00 ` Leizhen (ThunderTown)
2021-12-23 7:33 ` Leizhen (ThunderTown)
3 siblings, 1 reply; 17+ messages in thread
From: Leizhen (ThunderTown) @ 2021-12-22 8:00 UTC (permalink / raw)
To: Pingfan Liu, devicetree, linux-efi
Cc: Rob Herring, Catalin Marinas, Will Deacon, Andrew Morton,
Mike Rapoport, Geert Uytterhoeven, Frank Rowand, Ard Biesheuvel,
Nick Terrell, linux-arm-kernel
On 2021/12/15 10:13, Pingfan Liu wrote:
>
> diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
> index 18a2df431bfd..aa07ef5cab5f 100644
> --- a/drivers/of/fdt.c
> +++ b/drivers/of/fdt.c
> @@ -972,7 +972,7 @@ static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND;
> * location from flat tree
> * @node: reference to node containing usable memory range location ('chosen')
> */
> -static void __init early_init_dt_check_for_usable_mem_range(void)
> +void __init early_init_dt_check_for_usable_mem_range(void)
Why do I see a parameter 'node'?
master:
drivers/of/fdt.c:976:static void __init early_init_dt_check_for_usable_mem_range(unsigned long node)
next:
drivers/of/fdt.c:980:static void __init early_init_dt_check_for_usable_mem_range(unsigned long node)
> {
> const __be32 *prop;
> int len;
> diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
> index cf48983d3c86..ad09beb6d13c 100644
> --- a/include/linux/of_fdt.h
> +++ b/include/linux/of_fdt.h
> @@ -62,6 +62,7 @@ extern int early_init_dt_scan_chosen(unsigned long node, const char *uname,
> int depth, void *data);
> extern int early_init_dt_scan_memory(unsigned long node, const char *uname,
> int depth, void *data);
> +extern void early_init_dt_check_for_usable_mem_range(void);
> extern int early_init_dt_scan_chosen_stdout(void);
> extern void early_init_fdt_scan_reserved_mem(void);
> extern void early_init_fdt_reserve_self(void);
> @@ -86,6 +87,7 @@ extern void unflatten_and_copy_device_tree(void);
> extern void early_init_devtree(void *);
> extern void early_get_first_memblock_info(void *, phys_addr_t *);
> #else /* CONFIG_OF_EARLY_FLATTREE */
> +static inline void early_init_dt_check_for_usable_mem_range(void) {}
> static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; }
> static inline void early_init_fdt_scan_reserved_mem(void) {}
> static inline void early_init_fdt_reserve_self(void) {}
>
^ permalink raw reply [flat|nested] 17+ messages in thread
* Re: [PATCHv3] efi: apply memblock cap after memblock_add()
2021-12-22 8:00 ` Leizhen (ThunderTown)
@ 2021-12-23 7:33 ` Leizhen (ThunderTown)
0 siblings, 0 replies; 17+ messages in thread
From: Leizhen (ThunderTown) @ 2021-12-23 7:33 UTC (permalink / raw)
To: Pingfan Liu, devicetree, linux-efi
Cc: Rob Herring, Catalin Marinas, Will Deacon, Andrew Morton,
Mike Rapoport, Geert Uytterhoeven, Frank Rowand, Ard Biesheuvel,
Nick Terrell, linux-arm-kernel
On 2021/12/22 16:00, Leizhen (ThunderTown) wrote:
>
>
> On 2021/12/15 10:13, Pingfan Liu wrote:
>>
>> diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
>> index 18a2df431bfd..aa07ef5cab5f 100644
>> --- a/drivers/of/fdt.c
>> +++ b/drivers/of/fdt.c
>> @@ -972,7 +972,7 @@ static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND;
>> * location from flat tree
>> * @node: reference to node containing usable memory range location ('chosen')
>> */
>> -static void __init early_init_dt_check_for_usable_mem_range(void)
>> +void __init early_init_dt_check_for_usable_mem_range(void)
>
> Why do I see a parameter 'node'?
Sorry, I just saw that the patch 1/2 in v2 was also applied.
>
> master:
> drivers/of/fdt.c:976:static void __init early_init_dt_check_for_usable_mem_range(unsigned long node)
>
> next:
> drivers/of/fdt.c:980:static void __init early_init_dt_check_for_usable_mem_range(unsigned long node)
>
>> {
>> const __be32 *prop;
>> int len;
>> diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
>> index cf48983d3c86..ad09beb6d13c 100644
>> --- a/include/linux/of_fdt.h
>> +++ b/include/linux/of_fdt.h
>> @@ -62,6 +62,7 @@ extern int early_init_dt_scan_chosen(unsigned long node, const char *uname,
>> int depth, void *data);
>> extern int early_init_dt_scan_memory(unsigned long node, const char *uname,
>> int depth, void *data);
>> +extern void early_init_dt_check_for_usable_mem_range(void);
>> extern int early_init_dt_scan_chosen_stdout(void);
>> extern void early_init_fdt_scan_reserved_mem(void);
>> extern void early_init_fdt_reserve_self(void);
>> @@ -86,6 +87,7 @@ extern void unflatten_and_copy_device_tree(void);
>> extern void early_init_devtree(void *);
>> extern void early_get_first_memblock_info(void *, phys_addr_t *);
>> #else /* CONFIG_OF_EARLY_FLATTREE */
>> +static inline void early_init_dt_check_for_usable_mem_range(void) {}
>> static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; }
>> static inline void early_init_fdt_scan_reserved_mem(void) {}
>> static inline void early_init_fdt_reserve_self(void) {}
>>
^ permalink raw reply [flat|nested] 17+ messages in thread