* [PATCH] mm/memblock.c: fix index adjustment error in __next_mem_range_rev()
2016-07-25 18:52 ` Tejun Heo
@ 2016-07-26 15:03 ` zijun_hu
2016-07-26 16:50 ` Tejun Heo
2016-07-26 15:09 ` 答复: " zijun_hu
1 sibling, 1 reply; 5+ messages in thread
From: zijun_hu @ 2016-07-26 15:03 UTC (permalink / raw)
To: tj
Cc: akpm, kuleshovmail, ard.biesheuvel, tangchen, weiyang, dev,
david, linux-mm, linux-kernel, zhiyuan_zhu
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
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Hi Tejun,
I am sorry, I don't take any test for the patch attached in previous mail, and it can't fix the bug completely, please ignore it
I provide a new patch attached in this mail which pass test and can fix the issue described below
__next_mem_range_rev() defined in mm/memblock.c doesn't Achieve desired purpose if parameter type_b ==NULL
This new patch can fix the issue and get the last reversed region contained in type_a rightly
The new patch is descripted as follows
From 0e242eda7696f176a9a2e585a1db01f0575b39c9 Mon Sep 17 00:00:00 2001
From: zijun_hu <zijun_hu@htc.com>
Date: Mon, 25 Jul 2016 15:06:57 +0800
Subject: [PATCH] mm/memblock.c: fix index adjustment error in
__next_mem_range_rev()
fix region index adjustment error when parameter type_b of
__next_mem_range_rev() == NULL
Signed-off-by: zijun_hu <zijun_hu@htc.com>
---
mm/memblock.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/mm/memblock.c b/mm/memblock.c
index ac12489..cc5aeab 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -991,7 +991,11 @@ void __init_memblock __next_mem_range_rev(u64 *idx, int nid, ulong flags,
if (*idx == (u64)ULLONG_MAX) {
idx_a = type_a->cnt - 1;
- idx_b = type_b->cnt;
+ /* in order to get the last reversed region rightly */
+ if (type_b != NULL)
+ idx_b = type_b->cnt;
+ else
+ idx_b = 0;
}
for (; idx_a >= 0; idx_a--) {
@@ -1024,7 +1028,7 @@ void __init_memblock __next_mem_range_rev(u64 *idx, int nid, ulong flags,
*out_end = m_end;
if (out_nid)
*out_nid = m_nid;
- idx_a++;
+ idx_a--;
*idx = (u32)idx_a | (u64)idx_b << 32;
return;
}
--
1.9.1
Zijun Hu
Tel: +86 021 3813 0008 Ext: 8556
F1 Building, 299 Kang Wei Road, Pudong New Area,
Shanghai 201315, China
htc.com
-----ÓʼþÔ¼þ-----
·¢¼þÈË: Tejun Heo [mailto:htejun@gmail.com] ´ú±í Tejun Heo
·¢ËÍʱ¼ä: 2016Äê7ÔÂ26ÈÕ 2:52
ÊÕ¼þÈË: Zijun Hu(ºú×ÔÜŠ)
³ËÍ: akpm@linux-foundation.org; kuleshovmail@gmail.com; ard.biesheuvel@linaro.org; tangchen@cn.fujitsu.com; weiyang@linux.vnet.ibm.com; dev@g0hl1n.net; david@gibson.dropbear.id.au; linux-mm@kvack.org; linux-kernel@vger.kernel.org
Ö÷Ìâ: Re: [PATCH] mm/memblock.c: fix index adjustment error in __next_mem_range_rev()
On Mon, Jul 25, 2016 at 07:34:12AM +0000, zijun_hu@htc.com wrote:
> Hi All,
> There is a bug in mm/memblock.c
> Could you review and phase-in this patch?
> Thanks a lot
>
> From 3abf1822d30f77f126bd7a3c09bb243d9c17a029 Mon Sep 17 00:00:00 2001
> From: zijun_hu <zijun_hu@htc.com>
> Date: Mon, 25 Jul 2016 15:06:57 +0800
> Subject: [PATCH] mm/memblock.c: fix index adjustment error in
> __next_mem_range_rev()
>
> fix region index adjustment error when parameter type_b of
> __next_mem_range_rev() == NULL
>
> Signed-off-by: zijun_hu <zijun_hu@htc.com>
> ---
> mm/memblock.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/memblock.c b/mm/memblock.c index ac12489..b14973e
> 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -1024,7 +1024,7 @@ void __init_memblock __next_mem_range_rev(u64 *idx, int nid, ulong flags,
> *out_end = m_end;
> if (out_nid)
> *out_nid = m_nid;
> - idx_a++;
> + idx_a--;
Looks good to me. Do you happen to have a test case for this bug?
Thanks.
--
tejun
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From 0e242eda7696f176a9a2e585a1db01f0575b39c9 Mon Sep 17 00:00:00 2001
From: zijun_hu <zijun_hu@htc.com>
Date: Mon, 25 Jul 2016 15:06:57 +0800
Subject: [PATCH] mm/memblock.c: fix index adjustment error in
__next_mem_range_rev()
fix region index adjustment error when parameter type_b of
__next_mem_range_rev() == NULL
Signed-off-by: zijun_hu <zijun_hu@htc.com>
---
mm/memblock.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/mm/memblock.c b/mm/memblock.c
index ac12489..cc5aeab 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -991,7 +991,11 @@ void __init_memblock __next_mem_range_rev(u64 *idx, int nid, ulong flags,
if (*idx == (u64)ULLONG_MAX) {
idx_a = type_a->cnt - 1;
- idx_b = type_b->cnt;
+ /* in order to get the last reversed region rightly */
+ if (type_b != NULL)
+ idx_b = type_b->cnt;
+ else
+ idx_b = 0;
}
for (; idx_a >= 0; idx_a--) {
@@ -1024,7 +1028,7 @@ void __init_memblock __next_mem_range_rev(u64 *idx, int nid, ulong flags,
*out_end = m_end;
if (out_nid)
*out_nid = m_nid;
- idx_a++;
+ idx_a--;
*idx = (u32)idx_a | (u64)idx_b << 32;
return;
}
--
1.9.1
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH] mm/memblock.c: fix index adjustment error in __next_mem_range_rev()
2016-07-26 15:03 ` zijun_hu
@ 2016-07-26 16:50 ` Tejun Heo
0 siblings, 0 replies; 5+ messages in thread
From: Tejun Heo @ 2016-07-26 16:50 UTC (permalink / raw)
To: zijun_hu
Cc: akpm, kuleshovmail, ard.biesheuvel, tangchen, weiyang, dev,
david, linux-mm, linux-kernel, zhiyuan_zhu
Hello,
On Tue, Jul 26, 2016 at 03:03:58PM +0000, zijun_hu@htc.com wrote:
> I am sorry, I don't take any test for the patch attached in previous
> mail, and it can't fix the bug completely, please ignore it I
> provide a new patch attached in this mail which pass test and can
> fix the issue described below
>
> __next_mem_range_rev() defined in mm/memblock.c doesn't Achieve
> desired purpose if parameter type_b ==NULL This new patch can fix
> the issue and get the last reversed region contained in type_a
> rightly
Can you please flow future mails to 80 column?
> The new patch is descripted as follows
>
> From 0e242eda7696f176a9a2e585a1db01f0575b39c9 Mon Sep 17 00:00:00 2001
> From: zijun_hu <zijun_hu@htc.com>
> Date: Mon, 25 Jul 2016 15:06:57 +0800
> Subject: [PATCH] mm/memblock.c: fix index adjustment error in
> __next_mem_range_rev()
>
> fix region index adjustment error when parameter type_b of
> __next_mem_range_rev() == NULL
The patch is now fixing two bugs. It'd be nice to describe each in
the description and how the patch was tested.
> @@ -991,7 +991,11 @@ void __init_memblock __next_mem_range_rev(u64 *idx, int nid, ulong flags,
>
> if (*idx == (u64)ULLONG_MAX) {
> idx_a = type_a->cnt - 1;
> - idx_b = type_b->cnt;
> + /* in order to get the last reversed region rightly */
Before, it would trigger null deref. I don't think the above comment
is necessary.
> + if (type_b != NULL)
> + idx_b = type_b->cnt;
> + else
> + idx_b = 0;
> }
>
> for (; idx_a >= 0; idx_a--) {
> @@ -1024,7 +1028,7 @@ void __init_memblock __next_mem_range_rev(u64 *idx, int nid, ulong flags,
> *out_end = m_end;
> if (out_nid)
> *out_nid = m_nid;
> - idx_a++;
> + idx_a--;
> *idx = (u32)idx_a | (u64)idx_b << 32;
> return;
> }
Both changes look good to me. Provided the changes are tested,
Acked-by: Tejun Heo <tj@kernel.org>
Thanks.
--
tejun
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^ permalink raw reply [flat|nested] 5+ messages in thread
* 答复: [PATCH] mm/memblock.c: fix index adjustment error in __next_mem_range_rev()
2016-07-25 18:52 ` Tejun Heo
2016-07-26 15:03 ` zijun_hu
@ 2016-07-26 15:09 ` zijun_hu
1 sibling, 0 replies; 5+ messages in thread
From: zijun_hu @ 2016-07-26 15:09 UTC (permalink / raw)
To: tj
Cc: akpm, kuleshovmail, ard.biesheuvel, tangchen, weiyang, dev,
david, linux-mm, linux-kernel, zhiyuan_zhu
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1.1: Type: text/plain; charset="gb2312", Size: 4366 bytes --]
Hi Tejun,
I am sorry, I don't take any test for the patch attached in previous mail, and it can't fix the bug completely, please ignore it
I provide a new patch attached in this mail which pass test and can fix the issue described below
__next_mem_range_rev() defined in mm/memblock.c doesn't achieve desired purpose if parameter type_b ==NULL
This new patch can fix the issue and get the last reversed region contained in type_a rightly
The new patch is descripted as follows:
From 0e242eda7696f176a9a2e585a1db01f0575b39c9 Mon Sep 17 00:00:00 2001
From: zijun_hu <zijun_hu@htc.com<mailto:zijun_hu@htc.com>>
Date: Mon, 25 Jul 2016 15:06:57 +0800
Subject: [PATCH] mm/memblock.c: fix index adjustment error in
__next_mem_range_rev()
fix region index adjustment error when parameter type_b of
__next_mem_range_rev() == NULL
Signed-off-by: zijun_hu <zijun_hu@htc.com<mailto:zijun_hu@htc.com>>
---
mm/memblock.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/mm/memblock.c b/mm/memblock.c index ac12489..cc5aeab 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -991,7 +991,11 @@ void __init_memblock __next_mem_range_rev(u64 *idx, int nid, ulong flags,
if (*idx == (u64)ULLONG_MAX) {
idx_a = type_a->cnt - 1;
- idx_b = type_b->cnt;
+ /* in order to get the last reversed region rightly */
+ if (type_b != NULL)
+ idx_b = type_b->cnt;
+ else
+ idx_b = 0;
}
for (; idx_a >= 0; idx_a--) {
@@ -1024,7 +1028,7 @@ void __init_memblock __next_mem_range_rev(u64 *idx, int nid, ulong flags,
*out_end = m_end;
if (out_nid)
*out_nid = m_nid;
- idx_a++;
+ idx_a--;
*idx = (u32)idx_a | (u64)idx_b << 32;
return;
}
--
1.9.1
Zijun Hu
Tel: +86 021 3813 0008 Ext: 8556
F1 Building, 299 Kang Wei Road, Pudong New Area, Shanghai 201315, China htc.com
-----ÓʼþÔ¼þ-----
·¢¼þÈË: Tejun Heo [mailto:htejun@gmail.com]<mailto:[mailto:htejun@gmail.com]> ´ú±í Tejun Heo
·¢ËÍʱ¼ä: 2016Äê7ÔÂ26ÈÕ 2:52
ÊÕ¼þÈË: Zijun Hu(ºú×ÔÜŠ)
³ËÍ: akpm@linux-foundation.org<mailto:akpm@linux-foundation.org>; kuleshovmail@gmail.com<mailto:kuleshovmail@gmail.com>; ard.biesheuvel@linaro.org<mailto:ard.biesheuvel@linaro.org>; tangchen@cn.fujitsu.com<mailto:tangchen@cn.fujitsu.com>; weiyang@linux.vnet.ibm.com<mailto:weiyang@linux.vnet.ibm.com>; dev@g0hl1n.net<mailto:dev@g0hl1n.net>; david@gibson.dropbear.id.au<mailto:david@gibson.dropbear.id.au>; linux-mm@kvack.org<mailto:linux-mm@kvack.org>; linux-kernel@vger.kernel.org<mailto:linux-kernel@vger.kernel.org>
Ö÷Ìâ: Re: [PATCH] mm/memblock.c: fix index adjustment error in __next_mem_range_rev()
On Mon, Jul 25, 2016 at 07:34:12AM +0000, zijun_hu@htc.com<mailto:zijun_hu@htc.com> wrote:
> Hi All,
> There is a bug in mm/memblock.c
> Could you review and phase-in this patch?
> Thanks a lot
>
> From 3abf1822d30f77f126bd7a3c09bb243d9c17a029 Mon Sep 17 00:00:00 2001
> From: zijun_hu <zijun_hu@htc.com<mailto:zijun_hu@htc.com>>
> Date: Mon, 25 Jul 2016 15:06:57 +0800
> Subject: [PATCH] mm/memblock.c: fix index adjustment error in
> __next_mem_range_rev()
>
> fix region index adjustment error when parameter type_b of
> __next_mem_range_rev() == NULL
>
> Signed-off-by: zijun_hu <zijun_hu@htc.com<mailto:zijun_hu@htc.com>>
> ---
> mm/memblock.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/memblock.c b/mm/memblock.c index ac12489..b14973e
> 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -1024,7 +1024,7 @@ void __init_memblock __next_mem_range_rev(u64 *idx, int nid, ulong flags,
> *out_end = m_end;
> if (out_nid)
> *out_nid = m_nid;
> - idx_a++;
> + idx_a--;
Looks good to me. Do you happen to have a test case for this bug?
Thanks.
--
tejun
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From 0e242eda7696f176a9a2e585a1db01f0575b39c9 Mon Sep 17 00:00:00 2001
From: zijun_hu <zijun_hu@htc.com>
Date: Mon, 25 Jul 2016 15:06:57 +0800
Subject: [PATCH] mm/memblock.c: fix index adjustment error in
__next_mem_range_rev()
fix region index adjustment error when parameter type_b of
__next_mem_range_rev() == NULL
Signed-off-by: zijun_hu <zijun_hu@htc.com>
---
mm/memblock.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/mm/memblock.c b/mm/memblock.c
index ac12489..cc5aeab 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -991,7 +991,11 @@ void __init_memblock __next_mem_range_rev(u64 *idx, int nid, ulong flags,
if (*idx == (u64)ULLONG_MAX) {
idx_a = type_a->cnt - 1;
- idx_b = type_b->cnt;
+ /* in order to get the last reversed region rightly */
+ if (type_b != NULL)
+ idx_b = type_b->cnt;
+ else
+ idx_b = 0;
}
for (; idx_a >= 0; idx_a--) {
@@ -1024,7 +1028,7 @@ void __init_memblock __next_mem_range_rev(u64 *idx, int nid, ulong flags,
*out_end = m_end;
if (out_nid)
*out_nid = m_nid;
- idx_a++;
+ idx_a--;
*idx = (u32)idx_a | (u64)idx_b << 32;
return;
}
--
1.9.1
^ permalink raw reply [flat|nested] 5+ messages in thread