Regression in v4.0.0-rc1 with Android Binder

Message ID CAMi1Hd0frW_BqLwPQ7M_CKbA8-SeYhykwWYFZ-_iSre5r3zK7Q@mail.gmail.com
State New
Headers show

Commit Message

Amit Pundir Feb. 26, 2015, 10:04 p.m.
Hi,

I ran into series of following binder mmap failures with v4.0.0-rc1:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1971 at mm/vmalloc.c:130
vmap_page_range_noflush+0x119/0x144()
CPU: 0 PID: 1971 Comm: healthd Not tainted 4.0.0-rc1-00399-g7da3fdc-dirty #157
Hardware name: ARM-Versatile Express
[<c001246d>] (unwind_backtrace) from [<c000f7f9>] (show_stack+0x11/0x14)
[<c000f7f9>] (show_stack) from [<c049a221>] (dump_stack+0x59/0x7c)
[<c049a221>] (dump_stack) from [<c001cf21>] (warn_slowpath_common+0x55/0x84)
[<c001cf21>] (warn_slowpath_common) from [<c001cfe3>]
(warn_slowpath_null+0x17/0x1c)
[<c001cfe3>] (warn_slowpath_null) from [<c00c66c5>]
(vmap_page_range_noflush+0x119/0x144)
[<c00c66c5>] (vmap_page_range_noflush) from [<c00c716b>] (map_vm_area+0x27/0x48)
[<c00c716b>] (map_vm_area) from [<c038ddaf>]
(binder_update_page_range+0x12f/0x27c)
[<c038ddaf>] (binder_update_page_range) from [<c038e857>]
(binder_mmap+0xbf/0x1ac)
[<c038e857>] (binder_mmap) from [<c00c2dc7>] (mmap_region+0x2eb/0x4d4)
[<c00c2dc7>] (mmap_region) from [<c00c3197>] (do_mmap_pgoff+0x1e7/0x250)
[<c00c3197>] (do_mmap_pgoff) from [<c00b35b5>] (vm_mmap_pgoff+0x45/0x60)
[<c00b35b5>] (vm_mmap_pgoff) from [<c00c1f39>] (SyS_mmap_pgoff+0x5d/0x80)
[<c00c1f39>] (SyS_mmap_pgoff) from [<c000ce81>] (ret_fast_syscall+0x1/0x5c)
---[ end trace 48c2c4b9a1349e54 ]---
binder: 1982: binder_alloc_buf failed to map page at f0e00000 in kernel
binder: binder_mmap: 1982 b6bde000-b6cdc000 alloc small buf failed -12


Turned out that the following commit tripped off binder:
----------8<----------
commit 71394fe50146202f2c8d92cf50f5ebc761acf254
Author: Andrey Ryabinin <a.ryabinin@samsung.com>
Date:   Fri Feb 13 14:40:03 2015 -0800

    mm: vmalloc: add flag preventing guard hole allocation
---------->8----------


Explicitly disabling the vmalloc no guard (VM_NO_GUARD) flag in binder
worked fine for me. So does a fix like this look reasonable enough to
submit?
----------8<----------
                if (ret) {
---------->8----------


Regards,
Amit Pundir
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Comments

John Stultz Feb. 27, 2015, 5:26 p.m. | #1
On Fri, Feb 27, 2015 at 8:30 AM, Andrey Ryabinin <a.ryabinin@samsung.com> wrote:
> binder_update_page_range() initializes only addr and size
> fields in 'struct vm_struct tmp_area;' and passes it to
> map_vm_area().
>
> Before 71394fe50146 ("mm: vmalloc: add flag preventing guard hole allocation")
> this was because map_vm_area() didn't use any other fields
> in vm_struct except addr and size.
>
> Now get_vm_area_size() (used in map_vm_area()) reads vm_struct's
> flags to determine whether vm area has guard hole or not.
>
> binder_update_page_range() don't initialize flags field, so
> this causes following binder mmap failures:
> -----------[ cut here ]------------
> WARNING: CPU: 0 PID: 1971 at mm/vmalloc.c:130
> vmap_page_range_noflush+0x119/0x144()
> CPU: 0 PID: 1971 Comm: healthd Not tainted 4.0.0-rc1-00399-g7da3fdc-dirty #157
> Hardware name: ARM-Versatile Express
> [<c001246d>] (unwind_backtrace) from [<c000f7f9>] (show_stack+0x11/0x14)
> [<c000f7f9>] (show_stack) from [<c049a221>] (dump_stack+0x59/0x7c)
> [<c049a221>] (dump_stack) from [<c001cf21>] (warn_slowpath_common+0x55/0x84)
> [<c001cf21>] (warn_slowpath_common) from [<c001cfe3>]
> (warn_slowpath_null+0x17/0x1c)
> [<c001cfe3>] (warn_slowpath_null) from [<c00c66c5>]
> (vmap_page_range_noflush+0x119/0x144)
> [<c00c66c5>] (vmap_page_range_noflush) from [<c00c716b>] (map_vm_area+0x27/0x48)
> [<c00c716b>] (map_vm_area) from [<c038ddaf>]
> (binder_update_page_range+0x12f/0x27c)
> [<c038ddaf>] (binder_update_page_range) from [<c038e857>]
> (binder_mmap+0xbf/0x1ac)
> [<c038e857>] (binder_mmap) from [<c00c2dc7>] (mmap_region+0x2eb/0x4d4)
> [<c00c2dc7>] (mmap_region) from [<c00c3197>] (do_mmap_pgoff+0x1e7/0x250)
> [<c00c3197>] (do_mmap_pgoff) from [<c00b35b5>] (vm_mmap_pgoff+0x45/0x60)
> [<c00b35b5>] (vm_mmap_pgoff) from [<c00c1f39>] (SyS_mmap_pgoff+0x5d/0x80)
> [<c00c1f39>] (SyS_mmap_pgoff) from [<c000ce81>] (ret_fast_syscall+0x1/0x5c)
> ---[ end trace 48c2c4b9a1349e54 ]---
> binder: 1982: binder_alloc_buf failed to map page at f0e00000 in kernel
> binder: binder_mmap: 1982 b6bde000-b6cdc000 alloc small buf failed -12
>
> Use map_kernel_range_noflush() instead of map_vm_area() as this is better
> API for binder's purposes and it allows to get rid of 'vm_struct tmp_area' at all.
>
> Fixes: 71394fe50146 ("mm: vmalloc: add flag preventing guard hole allocation")
> Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
> Reported-by: Amit Pundir <amit.pundir@linaro.org>
> ---
>  drivers/android/binder.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index 33b09b6..a984fbb 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -551,7 +551,6 @@ static int binder_update_page_range(struct binder_proc *proc, int allocate,
>  {
>         void *page_addr;
>         unsigned long user_page_addr;
> -       struct vm_struct tmp_area;
>         struct page **page;
>         struct mm_struct *mm;
>
> @@ -600,9 +599,10 @@ static int binder_update_page_range(struct binder_proc *proc, int allocate,
>                                 proc->pid, page_addr);
>                         goto err_alloc_page_failed;
>                 }
> -               tmp_area.addr = page_addr;
> -               tmp_area.size = PAGE_SIZE + PAGE_SIZE /* guard page? */;
> -               ret = map_vm_area(&tmp_area, PAGE_KERNEL, page);
> +               ret = map_kernel_range_noflush((unsigned long)page_addr,
> +                                       PAGE_SIZE, PAGE_KERNEL, page);
> +               flush_cache_vmap((unsigned long)page_addr,
> +                               (unsigned long)page_addr + PAGE_SIZE);
>                 if (ret) {
>                         pr_err("%d: binder_alloc_buf failed to map page at %p in kernel\n",
>                                proc->pid, page_addr);

So with this patch I don't see the warnings, but I'm still seeing:
[   11.154283] binder: 1956: binder_alloc_buf failed to map page at
f0340000 in kernel
[   11.154916] binder: binder_mmap: 1956 b6ce0000-b6d00000 alloc small
buf failed -12

over and over.  So I don't think this patch is quite right.

thanks
-john
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/
John Stultz Feb. 27, 2015, 6:03 p.m. | #2
On Fri, Feb 27, 2015 at 9:44 AM, Andrey Ryabinin <a.ryabinin@samsung.com> wrote:
> binder_update_page_range() initializes only addr and size
> fields in 'struct vm_struct tmp_area;' and passes it to
> map_vm_area().
>
> Before 71394fe50146 ("mm: vmalloc: add flag preventing guard hole allocation")
> this was because map_vm_area() didn't use any other fields
> in vm_struct except addr and size.
>
> Now get_vm_area_size() (used in map_vm_area()) reads vm_struct's
> flags to determine whether vm area has guard hole or not.
>
> binder_update_page_range() don't initialize flags field, so
> this causes following binder mmap failures:
> -----------[ cut here ]------------
> WARNING: CPU: 0 PID: 1971 at mm/vmalloc.c:130
> vmap_page_range_noflush+0x119/0x144()
> CPU: 0 PID: 1971 Comm: healthd Not tainted 4.0.0-rc1-00399-g7da3fdc-dirty #157
> Hardware name: ARM-Versatile Express
> [<c001246d>] (unwind_backtrace) from [<c000f7f9>] (show_stack+0x11/0x14)
> [<c000f7f9>] (show_stack) from [<c049a221>] (dump_stack+0x59/0x7c)
> [<c049a221>] (dump_stack) from [<c001cf21>] (warn_slowpath_common+0x55/0x84)
> [<c001cf21>] (warn_slowpath_common) from [<c001cfe3>]
> (warn_slowpath_null+0x17/0x1c)
> [<c001cfe3>] (warn_slowpath_null) from [<c00c66c5>]
> (vmap_page_range_noflush+0x119/0x144)
> [<c00c66c5>] (vmap_page_range_noflush) from [<c00c716b>] (map_vm_area+0x27/0x48)
> [<c00c716b>] (map_vm_area) from [<c038ddaf>]
> (binder_update_page_range+0x12f/0x27c)
> [<c038ddaf>] (binder_update_page_range) from [<c038e857>]
> (binder_mmap+0xbf/0x1ac)
> [<c038e857>] (binder_mmap) from [<c00c2dc7>] (mmap_region+0x2eb/0x4d4)
> [<c00c2dc7>] (mmap_region) from [<c00c3197>] (do_mmap_pgoff+0x1e7/0x250)
> [<c00c3197>] (do_mmap_pgoff) from [<c00b35b5>] (vm_mmap_pgoff+0x45/0x60)
> [<c00b35b5>] (vm_mmap_pgoff) from [<c00c1f39>] (SyS_mmap_pgoff+0x5d/0x80)
> [<c00c1f39>] (SyS_mmap_pgoff) from [<c000ce81>] (ret_fast_syscall+0x1/0x5c)
> ---[ end trace 48c2c4b9a1349e54 ]---
> binder: 1982: binder_alloc_buf failed to map page at f0e00000 in kernel
> binder: binder_mmap: 1982 b6bde000-b6cdc000 alloc small buf failed -12
>
> Use map_kernel_range_noflush() instead of map_vm_area() as this is better
> API for binder's purposes and it allows to get rid of 'vm_struct tmp_area' at all.
>
> Fixes: 71394fe50146 ("mm: vmalloc: add flag preventing guard hole allocation")
> Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
> Reported-by: Amit Pundir <amit.pundir@linaro.org>
> ---
>  Changes since v1:
>    - fixed ret check after map_kernel_ranges_noflush().
>
>  drivers/android/binder.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index 33b09b6..6607f3c 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -551,7 +551,6 @@ static int binder_update_page_range(struct binder_proc *proc, int allocate,
>  {
>         void *page_addr;
>         unsigned long user_page_addr;
> -       struct vm_struct tmp_area;
>         struct page **page;
>         struct mm_struct *mm;
>
> @@ -600,10 +599,11 @@ static int binder_update_page_range(struct binder_proc *proc, int allocate,
>                                 proc->pid, page_addr);
>                         goto err_alloc_page_failed;
>                 }
> -               tmp_area.addr = page_addr;
> -               tmp_area.size = PAGE_SIZE + PAGE_SIZE /* guard page? */;
> -               ret = map_vm_area(&tmp_area, PAGE_KERNEL, page);
> -               if (ret) {
> +               ret = map_kernel_range_noflush((unsigned long)page_addr,
> +                                       PAGE_SIZE, PAGE_KERNEL, page);
> +               flush_cache_vmap((unsigned long)page_addr,
> +                               (unsigned long)page_addr + PAGE_SIZE);
> +               if (ret != 1) {
>                         pr_err("%d: binder_alloc_buf failed to map page at %p in kernel\n",
>                                proc->pid, page_addr);
>                         goto err_map_kernel_failed;


This seems to work better. Thanks!

Tested-by: John Stultz <john.stultz@linaro.org>

-john
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/
Amit Pundir March 1, 2015, 6:17 p.m. | #3
On 27 February 2015 at 23:14, Andrey Ryabinin <a.ryabinin@samsung.com> wrote:
> binder_update_page_range() initializes only addr and size
> fields in 'struct vm_struct tmp_area;' and passes it to
> map_vm_area().
>
> Before 71394fe50146 ("mm: vmalloc: add flag preventing guard hole allocation")
> this was because map_vm_area() didn't use any other fields
> in vm_struct except addr and size.
>
> Now get_vm_area_size() (used in map_vm_area()) reads vm_struct's
> flags to determine whether vm area has guard hole or not.
>
> binder_update_page_range() don't initialize flags field, so
> this causes following binder mmap failures:
> -----------[ cut here ]------------
> WARNING: CPU: 0 PID: 1971 at mm/vmalloc.c:130
> vmap_page_range_noflush+0x119/0x144()
> CPU: 0 PID: 1971 Comm: healthd Not tainted 4.0.0-rc1-00399-g7da3fdc-dirty #157
> Hardware name: ARM-Versatile Express
> [<c001246d>] (unwind_backtrace) from [<c000f7f9>] (show_stack+0x11/0x14)
> [<c000f7f9>] (show_stack) from [<c049a221>] (dump_stack+0x59/0x7c)
> [<c049a221>] (dump_stack) from [<c001cf21>] (warn_slowpath_common+0x55/0x84)
> [<c001cf21>] (warn_slowpath_common) from [<c001cfe3>]
> (warn_slowpath_null+0x17/0x1c)
> [<c001cfe3>] (warn_slowpath_null) from [<c00c66c5>]
> (vmap_page_range_noflush+0x119/0x144)
> [<c00c66c5>] (vmap_page_range_noflush) from [<c00c716b>] (map_vm_area+0x27/0x48)
> [<c00c716b>] (map_vm_area) from [<c038ddaf>]
> (binder_update_page_range+0x12f/0x27c)
> [<c038ddaf>] (binder_update_page_range) from [<c038e857>]
> (binder_mmap+0xbf/0x1ac)
> [<c038e857>] (binder_mmap) from [<c00c2dc7>] (mmap_region+0x2eb/0x4d4)
> [<c00c2dc7>] (mmap_region) from [<c00c3197>] (do_mmap_pgoff+0x1e7/0x250)
> [<c00c3197>] (do_mmap_pgoff) from [<c00b35b5>] (vm_mmap_pgoff+0x45/0x60)
> [<c00b35b5>] (vm_mmap_pgoff) from [<c00c1f39>] (SyS_mmap_pgoff+0x5d/0x80)
> [<c00c1f39>] (SyS_mmap_pgoff) from [<c000ce81>] (ret_fast_syscall+0x1/0x5c)
> ---[ end trace 48c2c4b9a1349e54 ]---
> binder: 1982: binder_alloc_buf failed to map page at f0e00000 in kernel
> binder: binder_mmap: 1982 b6bde000-b6cdc000 alloc small buf failed -12
>
> Use map_kernel_range_noflush() instead of map_vm_area() as this is better
> API for binder's purposes and it allows to get rid of 'vm_struct tmp_area' at all.
>
> Fixes: 71394fe50146 ("mm: vmalloc: add flag preventing guard hole allocation")
> Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
> Reported-by: Amit Pundir <amit.pundir@linaro.org>
> ---
>  Changes since v1:
>    - fixed ret check after map_kernel_ranges_noflush().
>
>  drivers/android/binder.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index 33b09b6..6607f3c 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -551,7 +551,6 @@ static int binder_update_page_range(struct binder_proc *proc, int allocate,
>  {
>         void *page_addr;
>         unsigned long user_page_addr;
> -       struct vm_struct tmp_area;
>         struct page **page;
>         struct mm_struct *mm;
>
> @@ -600,10 +599,11 @@ static int binder_update_page_range(struct binder_proc *proc, int allocate,
>                                 proc->pid, page_addr);
>                         goto err_alloc_page_failed;
>                 }
> -               tmp_area.addr = page_addr;
> -               tmp_area.size = PAGE_SIZE + PAGE_SIZE /* guard page? */;
> -               ret = map_vm_area(&tmp_area, PAGE_KERNEL, page);
> -               if (ret) {
> +               ret = map_kernel_range_noflush((unsigned long)page_addr,
> +                                       PAGE_SIZE, PAGE_KERNEL, page);
> +               flush_cache_vmap((unsigned long)page_addr,
> +                               (unsigned long)page_addr + PAGE_SIZE);
> +               if (ret != 1) {
>                         pr_err("%d: binder_alloc_buf failed to map page at %p in kernel\n",
>                                proc->pid, page_addr);
>                         goto err_map_kernel_failed;
> --

Works for me. Thanks.

Tested-by: Amit Pundir <amit.pundir@linaro.org>

> 2.3.0
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Patch hide | download patch | download mbox

--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -601,6 +601,7 @@  static int binder_update_page_range(struct
binder_proc *proc, int allocate,
                        goto err_alloc_page_failed;
                }
                tmp_area.addr = page_addr;
+               tmp_area.flags &= ~VM_NO_GUARD;
                tmp_area.size = PAGE_SIZE + PAGE_SIZE /* guard page? */;
                ret = map_vm_area(&tmp_area, PAGE_KERNEL, page);