Current THREAD_SIZE_ORDER implementation for m68k is incorrect, fix it by ilog2().
Fixes: cddafa3500fd ("m68k/m68knommu: merge MMU and non-MMU thread_info.h") Signed-off-by: Dawei Li dawei.li@shingroup.cn Cc: stable@vger.kernel.org --- arch/m68k/include/asm/thread_info.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/m68k/include/asm/thread_info.h b/arch/m68k/include/asm/thread_info.h index 31be2ad999ca..50faecd6fc5f 100644 --- a/arch/m68k/include/asm/thread_info.h +++ b/arch/m68k/include/asm/thread_info.h @@ -19,7 +19,8 @@ #else #define THREAD_SIZE PAGE_SIZE #endif -#define THREAD_SIZE_ORDER ((THREAD_SIZE / PAGE_SIZE) - 1) + +#define THREAD_SIZE_ORDER ilog2(THREAD_SIZE / PAGE_SIZE)
#ifndef __ASSEMBLY__
On 28. 02. 24, 9:58, Dawei Li wrote:
Current THREAD_SIZE_ORDER implementation for m68k is incorrect, fix it by ilog2().
This is not a good commit log. Incorrect in what way and why is the fixed version correct? And what is affected? Note you're referring to a change which was done 14 years ago. It definitely must not be that incorrect (for everybody).
Fixes: cddafa3500fd ("m68k/m68knommu: merge MMU and non-MMU thread_info.h") Signed-off-by: Dawei Li dawei.li@shingroup.cn Cc: stable@vger.kernel.org
arch/m68k/include/asm/thread_info.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/m68k/include/asm/thread_info.h b/arch/m68k/include/asm/thread_info.h index 31be2ad999ca..50faecd6fc5f 100644 --- a/arch/m68k/include/asm/thread_info.h +++ b/arch/m68k/include/asm/thread_info.h @@ -19,7 +19,8 @@ #else #define THREAD_SIZE PAGE_SIZE #endif -#define THREAD_SIZE_ORDER ((THREAD_SIZE / PAGE_SIZE) - 1)
+#define THREAD_SIZE_ORDER ilog2(THREAD_SIZE / PAGE_SIZE) #ifndef __ASSEMBLY__
Hi Jiri,
Thanks for quick review.
On Wed, Feb 28, 2024 at 10:11:05AM +0100, Jiri Slaby wrote:
On 28. 02. 24, 9:58, Dawei Li wrote:
Current THREAD_SIZE_ORDER implementation for m68k is incorrect, fix it by ilog2().
This is not a good commit log. Incorrect in what way and why is the fixed
Agreed.
version correct? And what is affected? Note you're referring to a change which was done 14 years ago. It definitely must not be that incorrect (for everybody).
It's 'right' just for current PAGE_SIZE & THREAD_SIZE configs:
// arch/m68k/include/asm/thread_info.h #if PAGE_SHIFT < 13 #ifdef CONFIG_4KSTACKS #define THREAD_SIZE 4096 #else #define THREAD_SIZE 8192 #endif #else #define THREAD_SIZE PAGE_SIZE #endif #define THREAD_SIZE_ORDER ((THREAD_SIZE / PAGE_SIZE) - 1)
// arch/m68k/include/asm/page.h #if defined(CONFIG_SUN3) || defined(CONFIG_COLDFIRE) #define PAGE_SHIFT 13 #else #define PAGE_SHIFT 12 #endif #define PAGE_SIZE (_AC(1, UL) << PAGE_SHIFT) #define PAGE_MASK (~(PAGE_SIZE-1)) #define PAGE_OFFSET (PAGE_OFFSET_RAW)
But it's incorrect in generic/mathematical way.
Thanks,
Dawei
Fixes: cddafa3500fd ("m68k/m68knommu: merge MMU and non-MMU thread_info.h") Signed-off-by: Dawei Li dawei.li@shingroup.cn Cc: stable@vger.kernel.org
arch/m68k/include/asm/thread_info.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/m68k/include/asm/thread_info.h b/arch/m68k/include/asm/thread_info.h index 31be2ad999ca..50faecd6fc5f 100644 --- a/arch/m68k/include/asm/thread_info.h +++ b/arch/m68k/include/asm/thread_info.h @@ -19,7 +19,8 @@ #else #define THREAD_SIZE PAGE_SIZE #endif -#define THREAD_SIZE_ORDER ((THREAD_SIZE / PAGE_SIZE) - 1)
+#define THREAD_SIZE_ORDER ilog2(THREAD_SIZE / PAGE_SIZE) #ifndef __ASSEMBLY__
-- js suse labs
Hi Dawei,
On Wed, Feb 28, 2024 at 10:34 AM Dawei Li dawei.li@shingroup.cn wrote:
On Wed, Feb 28, 2024 at 10:11:05AM +0100, Jiri Slaby wrote:
On 28. 02. 24, 9:58, Dawei Li wrote:
Current THREAD_SIZE_ORDER implementation for m68k is incorrect, fix it by ilog2().
This is not a good commit log. Incorrect in what way and why is the fixed
Agreed.
version correct? And what is affected? Note you're referring to a change which was done 14 years ago. It definitely must not be that incorrect (for everybody).
It's 'right' just for current PAGE_SIZE & THREAD_SIZE configs:
// arch/m68k/include/asm/thread_info.h #if PAGE_SHIFT < 13 #ifdef CONFIG_4KSTACKS #define THREAD_SIZE 4096 #else #define THREAD_SIZE 8192 #endif #else #define THREAD_SIZE PAGE_SIZE #endif #define THREAD_SIZE_ORDER ((THREAD_SIZE / PAGE_SIZE) - 1)
Indeed. The only supported values for THREAD_SIZE_ORDER on m68k are 0 and 1.
But it's incorrect in generic/mathematical way.
True. But does it matter much? I.e. do you plan to add support for larger values of THREAD_SIZE?
What about changing the #ifdeffery to set THREAD_SIZE_ORDER to an explicit value, and calculating THREAD_SIZE from THREAD_SIZE_ORDER instead?
Gr{oetje,eeting}s,
Geert
linux-stable-mirror@lists.linaro.org
-
Dawei Li -
Geert Uytterhoeven -
Jiri Slaby