[mm] c4344e8035: WARNING: CPU: 0 PID: 101 at mm/memory.c:303 __tlb_remove_page_size+0x25/0x99

3 messages, 2 authors, 2016-10-12 · open the first message on its own page

[mm] c4344e8035: WARNING: CPU: 0 PID: 101 at mm/memory.c:303 __tlb_remove_page_size+0x25/0x99

From: kernel test robot <hidden>
Date: 2016-10-11 20:48:02

FYI, we noticed the following commit:

https://github.com/0day-ci/linux Aneesh-Kumar-K-V/mm-Use-the-correct-page-size-when-removing-the-page/20161012-013446
commit c4344e80359420d7574b3b90fddf53311f1d24e6 ("mm: Remove the page size change check in tlb_remove_page")

in testcase: boot

on test machine: qemu-system-i386 -enable-kvm -cpu Haswell,+smep,+smap -m 360M

caused below changes:


+------------------------------------------------+------------+------------+
|                                                | eff764128d | c4344e8035 |
+------------------------------------------------+------------+------------+
| boot_successes                                 | 59         | 0          |
| boot_failures                                  | 0          | 43         |
| WARNING:at_mm/memory.c:#__tlb_remove_page_size | 0          | 43         |
| calltrace:SyS_execve                           | 0          | 43         |
| calltrace:run_init_process                     | 0          | 21         |
+------------------------------------------------+------------+------------+



[    4.096204] Write protecting the kernel text: 3148k
[    4.096911] Write protecting the kernel read-only data: 1444k
[    4.120357] ------------[ cut here ]------------
[    4.121078] WARNING: CPU: 0 PID: 101 at mm/memory.c:303 __tlb_remove_page_size+0x25/0x99
[    4.122380] Modules linked in:
[    4.122788] CPU: 0 PID: 101 Comm: run-parts Not tainted 4.8.0-mm1-00315-gc4344e8 #5
[    4.123956]  bd145dc4 b111e5e6 bd145de0 b10320dc 0000012f b10974d1 bd145e70 c4954170
[    4.125277]  c4954170 bd145df4 b103215f 00000009 00000000 00000000 bd145e04 b10974d1
[    4.126424]  c4954170 bd145e70 bd145e14 b10263ca bd145e70 bd47bafc bd145e40 b109767a
[    4.127622] Call Trace:
[    4.128255] ------------[ cut here ]------------
[    4.128261] WARNING: CPU: 0 PID: 103 at mm/memory.c:303 __tlb_remove_page_size+0x25/0x99
[    4.128261] Modules linked in:
[    4.128264] CPU: 0 PID: 103 Comm: sh Not tainted 4.8.0-mm1-00315-gc4344e8 #5
[    4.128268]  bd143dc4 b111e5e6 bd143de0 b10320dc 0000012f b10974d1 bd143e70 c494cd00
[    4.128271]  c494cd00 bd143df4 b103215f 00000009 00000000 00000000 bd143e04 b10974d1
[    4.128274]  c494cd00 bd143e70 bd143e14 b10263ca bd143e70 bd47dafc bd143e40 b109767a
[    4.128275] Call Trace:
[    4.128281]  [<b111e5e6>] dump_stack+0x16/0x18
[    4.128284]  [<b10320dc>] __warn+0xa5/0xbc
[    4.128286]  [<b10974d1>] ? __tlb_remove_page_size+0x25/0x99
[    4.128288]  [<b103215f>] warn_slowpath_null+0x11/0x16
[    4.128290]  [<b10974d1>] __tlb_remove_page_size+0x25/0x99
[    4.128293]  [<b10263ca>] ___pte_free_tlb+0x57/0x66
[    4.128295]  [<b109767a>] free_pgd_range+0x135/0x1d0
[    4.128298]  [<b10b6ad7>] setup_arg_pages+0x219/0x29a
[    4.128302]  [<b10db3a6>] load_elf_binary+0x2ad/0x94a
[    4.128305]  [<b11266fe>] ? _copy_from_user+0x49/0x5c
[    4.128307]  [<b10b6015>] search_binary_handler+0x106/0x159
[    4.128309]  [<b10b7558>] do_execveat_common+0x3bf/0x4dc
[    4.128311]  [<b10b7689>] do_execve+0x14/0x16
[    4.128313]  [<b10b780a>] SyS_execve+0x16/0x18
[    4.128316]  [<b1000d90>] do_fast_syscall_32+0x8f/0xce
[    4.128320]  [<b131145e>] sysenter_past_esp+0x47/0x75
[    4.128322] ---[ end trace 816334aebb0eaffe ]---
[    4.132981] ------------[ cut here ]------------





Thanks,
Kernel Test Robot

Re: [mm] c4344e8035: WARNING: CPU: 0 PID: 101 at mm/memory.c:303 __tlb_remove_page_size+0x25/0x99

From: Aneesh Kumar K.V <hidden>
Date: 2016-10-12 04:34:35

kernel test robot [off-list ref] writes:

FYI, we noticed the following commit:

https://github.com/0day-ci/linux Aneesh-Kumar-K-V/mm-Use-the-correct-page-size-when-removing-the-page/20161012-013446
commit c4344e80359420d7574b3b90fddf53311f1d24e6 ("mm: Remove the page size change check in tlb_remove_page")

in testcase: boot

on test machine: qemu-system-i386 -enable-kvm -cpu Haswell,+smep,+smap -m 360M

caused below changes:


+------------------------------------------------+------------+------------+
|                                                | eff764128d | c4344e8035 |
+------------------------------------------------+------------+------------+
| boot_successes                                 | 59         | 0          |
| boot_failures                                  | 0          | 43         |
| WARNING:at_mm/memory.c:#__tlb_remove_page_size | 0          | 43         |
| calltrace:SyS_execve                           | 0          | 43         |
| calltrace:run_init_process                     | 0          | 21         |
+------------------------------------------------+------------+------------+



[    4.096204] Write protecting the kernel text: 3148k
[    4.096911] Write protecting the kernel read-only data: 1444k
[    4.120357] ------------[ cut here ]------------
[    4.121078] WARNING: CPU: 0 PID: 101 at mm/memory.c:303 __tlb_remove_page_size+0x25/0x99
[    4.122380] Modules linked in:
[    4.122788] CPU: 0 PID: 101 Comm: run-parts Not tainted 4.8.0-mm1-00315-gc4344e8 #5
[    4.123956]  bd145dc4 b111e5e6 bd145de0 b10320dc 0000012f b10974d1 bd145e70 c4954170
[    4.125277]  c4954170 bd145df4 b103215f 00000009 00000000 00000000 bd145e04 b10974d1
[    4.126424]  c4954170 bd145e70 bd145e14 b10263ca bd145e70 bd47bafc bd145e40 b109767a
[    4.127622] Call Trace:

Thanks for the report. The below change should fix this.

commit 18c929e7cf672da617dc218c6265366bf78b1644
Author: Aneesh Kumar K.V [off-list ref]
Date:   Wed Oct 12 08:40:41 2016 +0530

    update mmu gather page size before flushing page table cache

diff --git a/mm/memory.c b/mm/memory.c
index 26d1ba8c87e6..7e7eccb82a2b 100644
--- a/mm/memory.c
+++ b/mm/memory.c

@@ -526,7 +526,11 @@ void free_pgd_range(struct mmu_gather *tlb,
 		end -= PMD_SIZE;
 	if (addr > end - 1)
 		return;
-
+	/*
+	 * We add page table cache pages with PAGE_SIZE,
+	 * (see pte_free_tlb()), flush the tlb if we need
+	 */
+	tlb_remove_check_page_size_change(tlb, PAGE_SIZE);
 	pgd = pgd_offset(tlb->mm, addr);
 	do {
 		next = pgd_addr_end(addr, end);

Re: [mm] c4344e8035: WARNING: CPU: 0 PID: 101 at mm/memory.c:303 __tlb_remove_page_size+0x25/0x99

From: Ye Xiaolong <hidden>
Date: 2016-10-12 07:15:32

On 10/12, Aneesh Kumar K.V wrote:

quoted hunk

kernel test robot [off-list ref] writes:

quoted

FYI, we noticed the following commit:

https://github.com/0day-ci/linux Aneesh-Kumar-K-V/mm-Use-the-correct-page-size-when-removing-the-page/20161012-013446
commit c4344e80359420d7574b3b90fddf53311f1d24e6 ("mm: Remove the page size change check in tlb_remove_page")

in testcase: boot

on test machine: qemu-system-i386 -enable-kvm -cpu Haswell,+smep,+smap -m 360M

caused below changes:


+------------------------------------------------+------------+------------+
|                                                | eff764128d | c4344e8035 |
+------------------------------------------------+------------+------------+
| boot_successes                                 | 59         | 0          |
| boot_failures                                  | 0          | 43         |
| WARNING:at_mm/memory.c:#__tlb_remove_page_size | 0          | 43         |
| calltrace:SyS_execve                           | 0          | 43         |
| calltrace:run_init_process                     | 0          | 21         |
+------------------------------------------------+------------+------------+



[    4.096204] Write protecting the kernel text: 3148k
[    4.096911] Write protecting the kernel read-only data: 1444k
[    4.120357] ------------[ cut here ]------------
[    4.121078] WARNING: CPU: 0 PID: 101 at mm/memory.c:303 __tlb_remove_page_size+0x25/0x99
[    4.122380] Modules linked in:
[    4.122788] CPU: 0 PID: 101 Comm: run-parts Not tainted 4.8.0-mm1-00315-gc4344e8 #5
[    4.123956]  bd145dc4 b111e5e6 bd145de0 b10320dc 0000012f b10974d1 bd145e70 c4954170
[    4.125277]  c4954170 bd145df4 b103215f 00000009 00000000 00000000 bd145e04 b10974d1
[    4.126424]  c4954170 bd145e70 bd145e14 b10263ca bd145e70 bd47bafc bd145e40 b109767a
[    4.127622] Call Trace:

Thanks for the report. The below change should fix this.

commit 18c929e7cf672da617dc218c6265366bf78b1644
Author: Aneesh Kumar K.V [off-list ref]
Date:   Wed Oct 12 08:40:41 2016 +0530

   update mmu gather page size before flushing page table cache

diff --git a/mm/memory.c b/mm/memory.c
index 26d1ba8c87e6..7e7eccb82a2b 100644
--- a/mm/memory.c
+++ b/mm/memory.c

@@ -526,7 +526,11 @@ void free_pgd_range(struct mmu_gather *tlb,

		end -= PMD_SIZE;
	if (addr > end - 1)
		return;
-
+	/*
+	 * We add page table cache pages with PAGE_SIZE,
+	 * (see pte_free_tlb()), flush the tlb if we need
+	 */
+	tlb_remove_check_page_size_change(tlb, PAGE_SIZE);
	pgd = pgd_offset(tlb->mm, addr);
	do {
		next = pgd_addr_end(addr, end);

Just applied this fix on top of commit c4344e8035 and confirmed that
reportedwarning is gone with this fix.

Tested-by: Xiaolong Ye <redacted>

=========================================================================================
compiler/kconfig/rootfs/sleep/tbox_group/testcase:
  gcc-6/i386-randconfig-s1-201641/quantal-core-i386.cgz/1/vm-vp-quantal-i386/boot

commit:
  c4344e80359420d7574b3b90fddf53311f1d24e6
  384db818365c90b91d8bad80be188765e801cf58 ("update mmu gather page size before flushing page table cache")

c4344e80359420d7 384db818365c90b91d8bad80be
---------------- --------------------------
       fail:runs  %reproduction    fail:runs
           |             |             |
         24:24        -100%            :5     dmesg.WARNING:at_mm/memory.c:#__tlb_remove_page_size

Thanks,
Xiaolong

`h`	back out one level
`j`	next message in thread
`k`	previous message in thread
`l`	drill in
`Esc`	close help / fold thread tree
`?`	toggle this help