diff mbox series

PM: hibernate: Fix level3 translation fault in swsusp_save()

Message ID 20240226034225.48689-1-13327272236@163.com
State New
Headers
Series PM: hibernate: Fix level3 translation fault in swsusp_save() |

Commit Message

Yaxiong Tian Feb. 26, 2024, 3:42 a.m. UTC 
  From: Yaxiong Tian <tianyaxiong@kylinos.cn>

On ARM64 machines using UEFI, if the linear map is not set (can_set_direct_map() 
return false), swsusp_save() will fail due to can't finding the map table 
under the nomap memory.such as:

[   48.532162] Unable to handle kernel paging request at virtual address ffffff8000000000
[   48.532162] Mem abort info:
[   48.532162]   ESR = 0x0000000096000007
[   48.532162]   EC = 0x25: DABT (current EL), IL = 32 bits
[   48.532162]   SET = 0, FnV = 0
[   48.532162]   EA = 0, S1PTW = 0
[   48.532162]   FSC = 0x07: level 3 translation fault
[   48.532162] Data abort info:
[   48.532162]   ISV = 0, ISS = 0x00000007, ISS2 = 0x00000000
[   48.532162]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[   48.532162]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[   48.532162] swapper pgtable: 4k pages, 39-bit VAs, pgdp=00000000eeb0b000
[   48.532162] [ffffff8000000000] pgd=180000217fff9803, p4d=180000217fff9803, pud=180000217fff9803, pmd=180000217fff8803, pte=0000000000000000
[   48.532162] Internal error: Oops: 0000000096000007 [#1] SMP
[   48.532162] Internal error: Oops: 0000000096000007 [#1] SMP
[   48.532162] Modules linked in: xt_multiport ipt_REJECT nf_reject_ipv4 xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c iptable_filter bpfilter rfkill at803x snd_hda_codec_hdmi snd_hda_intel snd_intel_dspcfg dwmac_generic stmmac_platform snd_hda_codec stmmac joydev pcs_xpcs snd_hda_core phylink ppdev lp parport ramoops reed_solomon ip_tables x_tables nls_iso8859_1 vfat multipath linear amdgpu amdxcp drm_exec gpu_sched drm_buddy hid_generic usbhid hid radeon video drm_suballoc_helper drm_ttm_helper ttm i2c_algo_bit drm_display_helper cec drm_kms_helper drm
[   48.532162] CPU: 0 PID: 3663 Comm: systemd-sleep Not tainted 6.6.2+ #76
[   48.532162] Source Version: 4e22ed63a0a48e7a7cff9b98b7806d8d4add7dc0
[   48.532162] Hardware name: Greatwall GW-XXXXXX-XXX/GW-XXXXXX-XXX, BIOS KunLun BIOS V4.0 01/19/2021
[   48.532162] pstate: 600003c5 (nZCv DAIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   48.532162] pc : swsusp_save+0x280/0x538
[   48.532162] lr : swsusp_save+0x280/0x538
[   48.532162] sp : ffffffa034a3fa40
[   48.532162] x29: ffffffa034a3fa40 x28: ffffff8000001000 x27: 0000000000000000
[   48.532162] x26: ffffff8001400000 x25: ffffffc08113e248 x24: 0000000000000000
[   48.532162] x23: 0000000000080000 x22: ffffffc08113e280 x21: 00000000000c69f2
[   48.532162] x20: ffffff8000000000 x19: ffffffc081ae2500 x18: 0000000000000000
[   48.532162] x17: 6666662074736420 x16: 3030303030303030 x15: 3038666666666666
[   48.532162] x14: 0000000000000b69 x13: ffffff9f89088530 x12: 00000000ffffffea
[   48.532162] x11: 00000000ffff7fff x10: 00000000ffff7fff x9 : ffffffc08193f0d0
[   48.532162] x8 : 00000000000bffe8 x7 : c0000000ffff7fff x6 : 0000000000000001
[   48.532162] x5 : ffffffa0fff09dc8 x4 : 0000000000000000 x3 : 0000000000000027
[   48.532162] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 000000000000004e
[   48.532162] Call trace:
[   48.532162]  swsusp_save+0x280/0x538
[   48.532162]  swsusp_arch_suspend+0x148/0x190
[   48.532162]  hibernation_snapshot+0x240/0x39c
[   48.532162]  hibernate+0xc4/0x378
[   48.532162]  state_store+0xf0/0x10c
[   48.532162]  kobj_attr_store+0x14/0x24

QEMU ARM64 using UEFI also has the problem by setting can_set_direct_map() 
return false.

Since the NOMAP regions are now marked as PageReserved(), pfn walkers
and the rest of core mm will treat them as unusable memory. So this
regions should not saved in hibernation.

This problem may cause by changes to pfn_valid() logic in commit
a7d9f306ba70 ("arm64: drop pfn_valid_within() and simplify pfn_valid()").

So to fix it, we add pfn_is_map_memory() check in saveable_page(). It
make such regisons don't save in hibernation.

Fixes: a7d9f306ba70 ("arm64: drop pfn_valid_within() and simplify pfn_valid()")
Co-developed-by: xiongxin <xiongxin@kylinos.cn>
Signed-off-by: xiongxin <xiongxin@kylinos.cn>
Signed-off-by: Yaxiong Tian <tianyaxiong@kylinos.cn>
---
 kernel/power/snapshot.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

David Hildenbrand Feb. 26, 2024, 8:37 a.m. UTC | #1 
On 26.02.24 04:42, Yaxiong Tian wrote:
> From: Yaxiong Tian <tianyaxiong@kylinos.cn>
> 
> On ARM64 machines using UEFI, if the linear map is not set (can_set_direct_map()
> return false), swsusp_save() will fail due to can't finding the map table
> under the nomap memory.such as:
> 
> [   48.532162] Unable to handle kernel paging request at virtual address ffffff8000000000
> [   48.532162] Mem abort info:
> [   48.532162]   ESR = 0x0000000096000007
> [   48.532162]   EC = 0x25: DABT (current EL), IL = 32 bits
> [   48.532162]   SET = 0, FnV = 0
> [   48.532162]   EA = 0, S1PTW = 0
> [   48.532162]   FSC = 0x07: level 3 translation fault
> [   48.532162] Data abort info:
> [   48.532162]   ISV = 0, ISS = 0x00000007, ISS2 = 0x00000000
> [   48.532162]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
> [   48.532162]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
> [   48.532162] swapper pgtable: 4k pages, 39-bit VAs, pgdp=00000000eeb0b000
> [   48.532162] [ffffff8000000000] pgd=180000217fff9803, p4d=180000217fff9803, pud=180000217fff9803, pmd=180000217fff8803, pte=0000000000000000
> [   48.532162] Internal error: Oops: 0000000096000007 [#1] SMP
> [   48.532162] Internal error: Oops: 0000000096000007 [#1] SMP
> [   48.532162] Modules linked in: xt_multiport ipt_REJECT nf_reject_ipv4 xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c iptable_filter bpfilter rfkill at803x snd_hda_codec_hdmi snd_hda_intel snd_intel_dspcfg dwmac_generic stmmac_platform snd_hda_codec stmmac joydev pcs_xpcs snd_hda_core phylink ppdev lp parport ramoops reed_solomon ip_tables x_tables nls_iso8859_1 vfat multipath linear amdgpu amdxcp drm_exec gpu_sched drm_buddy hid_generic usbhid hid radeon video drm_suballoc_helper drm_ttm_helper ttm i2c_algo_bit drm_display_helper cec drm_kms_helper drm
> [   48.532162] CPU: 0 PID: 3663 Comm: systemd-sleep Not tainted 6.6.2+ #76
> [   48.532162] Source Version: 4e22ed63a0a48e7a7cff9b98b7806d8d4add7dc0
> [   48.532162] Hardware name: Greatwall GW-XXXXXX-XXX/GW-XXXXXX-XXX, BIOS KunLun BIOS V4.0 01/19/2021
> [   48.532162] pstate: 600003c5 (nZCv DAIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> [   48.532162] pc : swsusp_save+0x280/0x538
> [   48.532162] lr : swsusp_save+0x280/0x538
> [   48.532162] sp : ffffffa034a3fa40
> [   48.532162] x29: ffffffa034a3fa40 x28: ffffff8000001000 x27: 0000000000000000
> [   48.532162] x26: ffffff8001400000 x25: ffffffc08113e248 x24: 0000000000000000
> [   48.532162] x23: 0000000000080000 x22: ffffffc08113e280 x21: 00000000000c69f2
> [   48.532162] x20: ffffff8000000000 x19: ffffffc081ae2500 x18: 0000000000000000
> [   48.532162] x17: 6666662074736420 x16: 3030303030303030 x15: 3038666666666666
> [   48.532162] x14: 0000000000000b69 x13: ffffff9f89088530 x12: 00000000ffffffea
> [   48.532162] x11: 00000000ffff7fff x10: 00000000ffff7fff x9 : ffffffc08193f0d0
> [   48.532162] x8 : 00000000000bffe8 x7 : c0000000ffff7fff x6 : 0000000000000001
> [   48.532162] x5 : ffffffa0fff09dc8 x4 : 0000000000000000 x3 : 0000000000000027
> [   48.532162] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 000000000000004e
> [   48.532162] Call trace:
> [   48.532162]  swsusp_save+0x280/0x538
> [   48.532162]  swsusp_arch_suspend+0x148/0x190
> [   48.532162]  hibernation_snapshot+0x240/0x39c
> [   48.532162]  hibernate+0xc4/0x378
> [   48.532162]  state_store+0xf0/0x10c
> [   48.532162]  kobj_attr_store+0x14/0x24
> 
> QEMU ARM64 using UEFI also has the problem by setting can_set_direct_map()
> return false.
> 
> Since the NOMAP regions are now marked as PageReserved(), pfn walkers
> and the rest of core mm will treat them as unusable memory. So this
> regions should not saved in hibernation.
> 
> This problem may cause by changes to pfn_valid() logic in commit
> a7d9f306ba70 ("arm64: drop pfn_valid_within() and simplify pfn_valid()").
> 
> So to fix it, we add pfn_is_map_memory() check in saveable_page(). It
> make such regisons don't save in hibernation.
> 
> Fixes: a7d9f306ba70 ("arm64: drop pfn_valid_within() and simplify pfn_valid()")
> Co-developed-by: xiongxin <xiongxin@kylinos.cn>
> Signed-off-by: xiongxin <xiongxin@kylinos.cn>
> Signed-off-by: Yaxiong Tian <tianyaxiong@kylinos.cn>
> ---
>   kernel/power/snapshot.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
> index 0f12e0a97e43..a06e3b1869d2 100644
> --- a/kernel/power/snapshot.c
> +++ b/kernel/power/snapshot.c
> @@ -1400,7 +1400,7 @@ static struct page *saveable_page(struct zone *zone, unsigned long pfn)
>   		return NULL;
>   
>   	if (PageReserved(page)
> -	    && (!kernel_page_present(page) || pfn_is_nosave(pfn)))
> +	    && (!kernel_page_present(page) || pfn_is_nosave(pfn) || !pfn_is_map_memory(pfn)))
>   		return NULL;
>   
>   	if (page_is_guard(page))

On top of which tree does this apply?

All occurrences of pfn_is_map_memory() are in arch/arm64, how does this 
compile on other architectures?
Mike Rapoport Feb. 26, 2024, 9:14 a.m. UTC | #2 
On Mon, Feb 26, 2024 at 09:37:06AM +0100, David Hildenbrand wrote:
> On 26.02.24 04:42, Yaxiong Tian wrote:
> > From: Yaxiong Tian <tianyaxiong@kylinos.cn>
> > 
> > On ARM64 machines using UEFI, if the linear map is not set (can_set_direct_map()
> > return false), swsusp_save() will fail due to can't finding the map table
> > under the nomap memory.such as:

can_set_direct_map() has nothing to do with presence or absence of the
linear map.

Do you mean that kernel_page_present() presumes that a page is present when
can_set_direct_map() returns false even for NOMAP ranges?

> > [   48.532162] Unable to handle kernel paging request at virtual address ffffff8000000000
> > [   48.532162] Mem abort info:
> > [   48.532162]   ESR = 0x0000000096000007
> > [   48.532162]   EC = 0x25: DABT (current EL), IL = 32 bits
> > [   48.532162]   SET = 0, FnV = 0
> > [   48.532162]   EA = 0, S1PTW = 0
> > [   48.532162]   FSC = 0x07: level 3 translation fault
> > [   48.532162] Data abort info:
> > [   48.532162]   ISV = 0, ISS = 0x00000007, ISS2 = 0x00000000
> > [   48.532162]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
> > [   48.532162]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
> > [   48.532162] swapper pgtable: 4k pages, 39-bit VAs, pgdp=00000000eeb0b000
> > [   48.532162] [ffffff8000000000] pgd=180000217fff9803, p4d=180000217fff9803, pud=180000217fff9803, pmd=180000217fff8803, pte=0000000000000000
> > [   48.532162] Internal error: Oops: 0000000096000007 [#1] SMP
> > [   48.532162] Internal error: Oops: 0000000096000007 [#1] SMP
> > [   48.532162] Modules linked in: xt_multiport ipt_REJECT nf_reject_ipv4 xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c iptable_filter bpfilter rfkill at803x snd_hda_codec_hdmi snd_hda_intel snd_intel_dspcfg dwmac_generic stmmac_platform snd_hda_codec stmmac joydev pcs_xpcs snd_hda_core phylink ppdev lp parport ramoops reed_solomon ip_tables x_tables nls_iso8859_1 vfat multipath linear amdgpu amdxcp drm_exec gpu_sched drm_buddy hid_generic usbhid hid radeon video drm_suballoc_helper drm_ttm_helper ttm i2c_algo_bit drm_display_helper cec drm_kms_helper drm
> > [   48.532162] CPU: 0 PID: 3663 Comm: systemd-sleep Not tainted 6.6.2+ #76
> > [   48.532162] Source Version: 4e22ed63a0a48e7a7cff9b98b7806d8d4add7dc0
> > [   48.532162] Hardware name: Greatwall GW-XXXXXX-XXX/GW-XXXXXX-XXX, BIOS KunLun BIOS V4.0 01/19/2021
> > [   48.532162] pstate: 600003c5 (nZCv DAIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> > [   48.532162] pc : swsusp_save+0x280/0x538
> > [   48.532162] lr : swsusp_save+0x280/0x538
> > [   48.532162] sp : ffffffa034a3fa40
> > [   48.532162] x29: ffffffa034a3fa40 x28: ffffff8000001000 x27: 0000000000000000
> > [   48.532162] x26: ffffff8001400000 x25: ffffffc08113e248 x24: 0000000000000000
> > [   48.532162] x23: 0000000000080000 x22: ffffffc08113e280 x21: 00000000000c69f2
> > [   48.532162] x20: ffffff8000000000 x19: ffffffc081ae2500 x18: 0000000000000000
> > [   48.532162] x17: 6666662074736420 x16: 3030303030303030 x15: 3038666666666666
> > [   48.532162] x14: 0000000000000b69 x13: ffffff9f89088530 x12: 00000000ffffffea
> > [   48.532162] x11: 00000000ffff7fff x10: 00000000ffff7fff x9 : ffffffc08193f0d0
> > [   48.532162] x8 : 00000000000bffe8 x7 : c0000000ffff7fff x6 : 0000000000000001
> > [   48.532162] x5 : ffffffa0fff09dc8 x4 : 0000000000000000 x3 : 0000000000000027
> > [   48.532162] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 000000000000004e
> > [   48.532162] Call trace:
> > [   48.532162]  swsusp_save+0x280/0x538
> > [   48.532162]  swsusp_arch_suspend+0x148/0x190
> > [   48.532162]  hibernation_snapshot+0x240/0x39c
> > [   48.532162]  hibernate+0xc4/0x378
> > [   48.532162]  state_store+0xf0/0x10c
> > [   48.532162]  kobj_attr_store+0x14/0x24
> > 
> > QEMU ARM64 using UEFI also has the problem by setting can_set_direct_map()
> > return false.

Huh?
Why would you do that?

> > 
> > Since the NOMAP regions are now marked as PageReserved(), pfn walkers
> > and the rest of core mm will treat them as unusable memory. So this
> > regions should not saved in hibernation.
> > 
> > This problem may cause by changes to pfn_valid() logic in commit
> > a7d9f306ba70 ("arm64: drop pfn_valid_within() and simplify pfn_valid()").
> > 
> > So to fix it, we add pfn_is_map_memory() check in saveable_page(). It
> > make such regisons don't save in hibernation.
> > 
> > Fixes: a7d9f306ba70 ("arm64: drop pfn_valid_within() and simplify pfn_valid()")
> > Co-developed-by: xiongxin <xiongxin@kylinos.cn>
> > Signed-off-by: xiongxin <xiongxin@kylinos.cn>
> > Signed-off-by: Yaxiong Tian <tianyaxiong@kylinos.cn>
> > ---
> >   kernel/power/snapshot.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
> > index 0f12e0a97e43..a06e3b1869d2 100644
> > --- a/kernel/power/snapshot.c
> > +++ b/kernel/power/snapshot.c
> > @@ -1400,7 +1400,7 @@ static struct page *saveable_page(struct zone *zone, unsigned long pfn)
> >   		return NULL;
> >   	if (PageReserved(page)
> > -	    && (!kernel_page_present(page) || pfn_is_nosave(pfn)))
> > +	    && (!kernel_page_present(page) || pfn_is_nosave(pfn) || !pfn_is_map_memory(pfn)))

I think adding the check for !pfn_is_map_memory() to arm64::pfn_is_nosave()
is the best way to fix this.

> >   		return NULL;
> >   	if (page_is_guard(page))
> 
> On top of which tree does this apply?
> 
> All occurrences of pfn_is_map_memory() are in arch/arm64, how does this
> compile on other architectures?
> 
> -- 
> Cheers,
> 
> David / dhildenb
>
Yaxiong Tian Feb. 27, 2024, 7:51 a.m. UTC | #3 
在 2024/2/26 17:14, Mike Rapoport 写道:
> On Mon, Feb 26, 2024 at 09:37:06AM +0100, David Hildenbrand wrote:
>> On 26.02.24 04:42, Yaxiong Tian wrote:
>>> From: Yaxiong Tian <tianyaxiong@kylinos.cn>
>>>
>>> On ARM64 machines using UEFI, if the linear map is not set (can_set_direct_map()
>>> return false), swsusp_save() will fail due to can't finding the map table
>>> under the nomap memory.such as:
> can_set_direct_map() has nothing to do with presence or absence of the
> linear map.
>
> Do you mean that kernel_page_present() presumes that a page is present when
> can_set_direct_map() returns false even for NOMAP ranges?
Yes， in swsusp_save()->copy_data_pages()->page_is_saveable(),
kernel_page_present() presumes that a page is present when 
can_set_direct_map()
returns false even for NOMAP ranges.So NOMAP pages will saved in 
after,and then
cause level3 translation fault in this pages.
>>> [   48.532162] Unable to handle kernel paging request at virtual address ffffff8000000000
>>> [   48.532162] Mem abort info:
>>> [   48.532162]   ESR = 0x0000000096000007
>>> [   48.532162]   EC = 0x25: DABT (current EL), IL = 32 bits
>>> [   48.532162]   SET = 0, FnV = 0
>>> [   48.532162]   EA = 0, S1PTW = 0
>>> [   48.532162]   FSC = 0x07: level 3 translation fault
>>> [   48.532162] Data abort info:
>>> [   48.532162]   ISV = 0, ISS = 0x00000007, ISS2 = 0x00000000
>>> [   48.532162]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
>>> [   48.532162]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
>>> [   48.532162] swapper pgtable: 4k pages, 39-bit VAs, pgdp=00000000eeb0b000
>>> [   48.532162] [ffffff8000000000] pgd=180000217fff9803, p4d=180000217fff9803, pud=180000217fff9803, pmd=180000217fff8803, pte=0000000000000000
>>> [   48.532162] Internal error: Oops: 0000000096000007 [#1] SMP
>>> [   48.532162] Internal error: Oops: 0000000096000007 [#1] SMP
>>> [   48.532162] Modules linked in: xt_multiport ipt_REJECT nf_reject_ipv4 xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c iptable_filter bpfilter rfkill at803x snd_hda_codec_hdmi snd_hda_intel snd_intel_dspcfg dwmac_generic stmmac_platform snd_hda_codec stmmac joydev pcs_xpcs snd_hda_core phylink ppdev lp parport ramoops reed_solomon ip_tables x_tables nls_iso8859_1 vfat multipath linear amdgpu amdxcp drm_exec gpu_sched drm_buddy hid_generic usbhid hid radeon video drm_suballoc_helper drm_ttm_helper ttm i2c_algo_bit drm_display_helper cec drm_kms_helper drm
>>> [   48.532162] CPU: 0 PID: 3663 Comm: systemd-sleep Not tainted 6.6.2+ #76
>>> [   48.532162] Source Version: 4e22ed63a0a48e7a7cff9b98b7806d8d4add7dc0
>>> [   48.532162] Hardware name: Greatwall GW-XXXXXX-XXX/GW-XXXXXX-XXX, BIOS KunLun BIOS V4.0 01/19/2021
>>> [   48.532162] pstate: 600003c5 (nZCv DAIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
>>> [   48.532162] pc : swsusp_save+0x280/0x538
>>> [   48.532162] lr : swsusp_save+0x280/0x538
>>> [   48.532162] sp : ffffffa034a3fa40
>>> [   48.532162] x29: ffffffa034a3fa40 x28: ffffff8000001000 x27: 0000000000000000
>>> [   48.532162] x26: ffffff8001400000 x25: ffffffc08113e248 x24: 0000000000000000
>>> [   48.532162] x23: 0000000000080000 x22: ffffffc08113e280 x21: 00000000000c69f2
>>> [   48.532162] x20: ffffff8000000000 x19: ffffffc081ae2500 x18: 0000000000000000
>>> [   48.532162] x17: 6666662074736420 x16: 3030303030303030 x15: 3038666666666666
>>> [   48.532162] x14: 0000000000000b69 x13: ffffff9f89088530 x12: 00000000ffffffea
>>> [   48.532162] x11: 00000000ffff7fff x10: 00000000ffff7fff x9 : ffffffc08193f0d0
>>> [   48.532162] x8 : 00000000000bffe8 x7 : c0000000ffff7fff x6 : 0000000000000001
>>> [   48.532162] x5 : ffffffa0fff09dc8 x4 : 0000000000000000 x3 : 0000000000000027
>>> [   48.532162] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 000000000000004e
>>> [   48.532162] Call trace:
>>> [   48.532162]  swsusp_save+0x280/0x538
>>> [   48.532162]  swsusp_arch_suspend+0x148/0x190
>>> [   48.532162]  hibernation_snapshot+0x240/0x39c
>>> [   48.532162]  hibernate+0xc4/0x378
>>> [   48.532162]  state_store+0xf0/0x10c
>>> [   48.532162]  kobj_attr_store+0x14/0x24
>>>
>>> QEMU ARM64 using UEFI also has the problem by setting can_set_direct_map()
>>> return false.
> Huh?
> Why would you do that?
I discovered this problem when upgrading from 5.4 to 6.6 using the 5.4 
configuration.
So I using latest linux-next code,find the problem still exist.To rule 
out the effects
of a particular machine，I also use qemu to check it.
>
>>> Since the NOMAP regions are now marked as PageReserved(), pfn walkers
>>> and the rest of core mm will treat them as unusable memory. So this
>>> regions should not saved in hibernation.
>>>
>>> This problem may cause by changes to pfn_valid() logic in commit
>>> a7d9f306ba70 ("arm64: drop pfn_valid_within() and simplify pfn_valid()").
>>>
>>> So to fix it, we add pfn_is_map_memory() check in saveable_page(). It
>>> make such regisons don't save in hibernation.
>>>
>>> Fixes: a7d9f306ba70 ("arm64: drop pfn_valid_within() and simplify pfn_valid()")
>>> Co-developed-by: xiongxin <xiongxin@kylinos.cn>
>>> Signed-off-by: xiongxin <xiongxin@kylinos.cn>
>>> Signed-off-by: Yaxiong Tian <tianyaxiong@kylinos.cn>
>>> ---
>>>    kernel/power/snapshot.c | 2 +-
>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
>>> index 0f12e0a97e43..a06e3b1869d2 100644
>>> --- a/kernel/power/snapshot.c
>>> +++ b/kernel/power/snapshot.c
>>> @@ -1400,7 +1400,7 @@ static struct page *saveable_page(struct zone *zone, unsigned long pfn)
>>>    		return NULL;
>>>    	if (PageReserved(page)
>>> -	    && (!kernel_page_present(page) || pfn_is_nosave(pfn)))
>>> +	    && (!kernel_page_present(page) || pfn_is_nosave(pfn) || !pfn_is_map_memory(pfn)))
> I think adding the check for !pfn_is_map_memory() to arm64::pfn_is_nosave()
> is the best way to fix this.
Thinks, I also think this is the best modification.
>>>    		return NULL;
>>>    	if (page_is_guard(page))
>> On top of which tree does this apply?
>>
>> All occurrences of pfn_is_map_memory() are in arch/arm64, how does this
>> compile on other architectures?
>>
>> -- 
>> Cheers,
>>
>> David / dhildenb
>>
Mike Rapoport Feb. 29, 2024, 9:42 a.m. UTC | #4 
On Tue, Feb 27, 2024 at 03:51:25PM +0800, Yaxiong Tian wrote:
> 
> 在 2024/2/26 17:14, Mike Rapoport 写道:
> > On Mon, Feb 26, 2024 at 09:37:06AM +0100, David Hildenbrand wrote:
> > > On 26.02.24 04:42, Yaxiong Tian wrote:
> > > > From: Yaxiong Tian <tianyaxiong@kylinos.cn>
> > > > 
> > > > On ARM64 machines using UEFI, if the linear map is not set (can_set_direct_map()
> > > > return false), swsusp_save() will fail due to can't finding the map table
> > > > under the nomap memory.such as:
> > can_set_direct_map() has nothing to do with presence or absence of the
> > linear map.
> > 
> > Do you mean that kernel_page_present() presumes that a page is present when
> > can_set_direct_map() returns false even for NOMAP ranges?
> Yes， in swsusp_save()->copy_data_pages()->page_is_saveable(),
> kernel_page_present() presumes that a page is present when
> can_set_direct_map()
> returns false even for NOMAP ranges.So NOMAP pages will saved in after,and
> then
> cause level3 translation fault in this pages.

So this should be the description of the problem in the changelog rather
than saying "if the linear map is not set (can_set_direct_map() return
false)"

> > > > QEMU ARM64 using UEFI also has the problem by setting can_set_direct_map()
> > > > return false.
> >
> > Huh?
> > Why would you do that?
> >
> I discovered this problem when upgrading from 5.4 to 6.6 using the 5.4
> configuration.
> So I using latest linux-next code,find the problem still exist.To rule out
> the effects
> of a particular machine，I also use qemu to check it.

I believe this can be reproduced if you boot with rodata=off and then
a better description would be something like

	This issue can be reproduced in QEMU when booting with rodata=off
Yaxiong Tian March 1, 2024, 2:55 a.m. UTC | #5 
在 2024/2/29 17:42, Mike Rapoport 写道:
> On Tue, Feb 27, 2024 at 03:51:25PM +0800, Yaxiong Tian wrote:
>> 在 2024/2/26 17:14, Mike Rapoport 写道:
>>> On Mon, Feb 26, 2024 at 09:37:06AM +0100, David Hildenbrand wrote:
>>>> On 26.02.24 04:42, Yaxiong Tian wrote:
>>>>> From: Yaxiong Tian <tianyaxiong@kylinos.cn>
>>>>>
>>>>> On ARM64 machines using UEFI, if the linear map is not set (can_set_direct_map()
>>>>> return false), swsusp_save() will fail due to can't finding the map table
>>>>> under the nomap memory.such as:
>>> can_set_direct_map() has nothing to do with presence or absence of the
>>> linear map.
>>>
>>> Do you mean that kernel_page_present() presumes that a page is present when
>>> can_set_direct_map() returns false even for NOMAP ranges?
>> Yes， in swsusp_save()->copy_data_pages()->page_is_saveable(),
>> kernel_page_present() presumes that a page is present when
>> can_set_direct_map()
>> returns false even for NOMAP ranges.So NOMAP pages will saved in after,and
>> then
>> cause level3 translation fault in this pages.
> So this should be the description of the problem in the changelog rather
> than saying "if the linear map is not set (can_set_direct_map() return
> false)"
>
>>>>> QEMU ARM64 using UEFI also has the problem by setting can_set_direct_map()
>>>>> return false.
>>> Huh?
>>> Why would you do that?
>>>
>> I discovered this problem when upgrading from 5.4 to 6.6 using the 5.4
>> configuration.
>> So I using latest linux-next code,find the problem still exist.To rule out
>> the effects
>> of a particular machine，I also use qemu to check it.
> I believe this can be reproduced if you boot with rodata=off and then
> a better description would be something like
>
> 	This issue can be reproduced in QEMU when booting with rodata=off

Thanks, I opt commit messages,and move !pfn_is_map_memory() check from 
page_is_saveable()
to arm64::pfn_is_nosave().  The patch v2 is in:

https://lore.kernel.org/all/20240301021924.33210-1-13327272236@163.com/

I heard that if it is a single PATCH it should be placed under the 
original mailing list,
so please ignore the February 27 patch mailing.

>
diff mbox series

Patch

diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 0f12e0a97e43..a06e3b1869d2 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -1400,7 +1400,7 @@  static struct page *saveable_page(struct zone *zone, unsigned long pfn)
 		return NULL;
 
 	if (PageReserved(page)
-	    && (!kernel_page_present(page) || pfn_is_nosave(pfn)))
+	    && (!kernel_page_present(page) || pfn_is_nosave(pfn) || !pfn_is_map_memory(pfn)))
 		return NULL;
 
 	if (page_is_guard(page))