* Re: [PATCH v2] Fix display of Maximum Memory
2020-01-15 14:53 [PATCH v2] Fix display of Maximum Memory Michael Bringmann
@ 2020-01-15 14:55 ` Christophe Leroy
2020-01-16 0:07 ` Tyrel Datwyler
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: Christophe Leroy @ 2020-01-15 14:55 UTC (permalink / raw)
To: Michael Bringmann, linuxppc-dev, linux-kernel, Michael Ellerman,
Gustavo Walbon, Paul Mackerras
Le 15/01/2020 à 15:53, Michael Bringmann a écrit :
> Correct overflow problem in calculation+display of Maximum Memory
> value to syscfg where 32bits is insufficient.
>
> Signed-off-by: Michael Bringmann <mwb@linux.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
> ---
> arch/powerpc/platforms/pseries/lparcfg.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/platforms/pseries/lparcfg.c b/arch/powerpc/platforms/pseries/lparcfg.c
> index e33e8bc..f00411c 100644
> --- a/arch/powerpc/platforms/pseries/lparcfg.c
> +++ b/arch/powerpc/platforms/pseries/lparcfg.c
> @@ -433,12 +433,12 @@ static void parse_em_data(struct seq_file *m)
>
> static void maxmem_data(struct seq_file *m)
> {
> - unsigned long maxmem = 0;
> + u64 maxmem = 0;
>
> - maxmem += drmem_info->n_lmbs * drmem_info->lmb_size;
> - maxmem += hugetlb_total_pages() * PAGE_SIZE;
> + maxmem += (u64)drmem_info->n_lmbs * drmem_info->lmb_size;
> + maxmem += (u64)hugetlb_total_pages() * PAGE_SIZE;
>
> - seq_printf(m, "MaxMem=%ld\n", maxmem);
> + seq_printf(m, "MaxMem=%llu\n", maxmem);
> }
>
> static int pseries_lparcfg_data(struct seq_file *m, void *v)
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2] Fix display of Maximum Memory
2020-01-15 14:53 [PATCH v2] Fix display of Maximum Memory Michael Bringmann
2020-01-15 14:55 ` Christophe Leroy
@ 2020-01-16 0:07 ` Tyrel Datwyler
2020-01-16 5:53 ` Michael Ellerman
2020-01-29 5:17 ` Michael Ellerman
3 siblings, 0 replies; 6+ messages in thread
From: Tyrel Datwyler @ 2020-01-16 0:07 UTC (permalink / raw)
To: Michael Bringmann, linuxppc-dev, linux-kernel, Michael Ellerman,
Gustavo Walbon, Paul Mackerras
On 1/15/20 6:53 AM, Michael Bringmann wrote:
> Correct overflow problem in calculation+display of Maximum Memory
> value to syscfg where 32bits is insufficient.
>
Probably needs the following Fixes tag:
Fixes: 772b039fd9a7 ("powerpc/pseries: Export maximum memory value")
otherwise,
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
> Signed-off-by: Michael Bringmann <mwb@linux.ibm.com>
> ---
> arch/powerpc/platforms/pseries/lparcfg.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/platforms/pseries/lparcfg.c b/arch/powerpc/platforms/pseries/lparcfg.c
> index e33e8bc..f00411c 100644
> --- a/arch/powerpc/platforms/pseries/lparcfg.c
> +++ b/arch/powerpc/platforms/pseries/lparcfg.c
> @@ -433,12 +433,12 @@ static void parse_em_data(struct seq_file *m)
>
> static void maxmem_data(struct seq_file *m)
> {
> - unsigned long maxmem = 0;
> + u64 maxmem = 0;
>
> - maxmem += drmem_info->n_lmbs * drmem_info->lmb_size;
> - maxmem += hugetlb_total_pages() * PAGE_SIZE;
> + maxmem += (u64)drmem_info->n_lmbs * drmem_info->lmb_size;
> + maxmem += (u64)hugetlb_total_pages() * PAGE_SIZE;
>
> - seq_printf(m, "MaxMem=%ld\n", maxmem);
> + seq_printf(m, "MaxMem=%llu\n", maxmem);
> }
>
> static int pseries_lparcfg_data(struct seq_file *m, void *v)
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2] Fix display of Maximum Memory
2020-01-15 14:53 [PATCH v2] Fix display of Maximum Memory Michael Bringmann
2020-01-15 14:55 ` Christophe Leroy
2020-01-16 0:07 ` Tyrel Datwyler
@ 2020-01-16 5:53 ` Michael Ellerman
2020-01-16 23:52 ` Michael Bringmann
2020-01-29 5:17 ` Michael Ellerman
3 siblings, 1 reply; 6+ messages in thread
From: Michael Ellerman @ 2020-01-16 5:53 UTC (permalink / raw)
To: Michael Bringmann, linuxppc-dev, linux-kernel, Gustavo Walbon,
Paul Mackerras
Michael Bringmann <mwb@linux.ibm.com> writes:
> Correct overflow problem in calculation+display of Maximum Memory
> value to syscfg where 32bits is insufficient.
>
> Signed-off-by: Michael Bringmann <mwb@linux.ibm.com>
> ---
> arch/powerpc/platforms/pseries/lparcfg.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/platforms/pseries/lparcfg.c b/arch/powerpc/platforms/pseries/lparcfg.c
> index e33e8bc..f00411c 100644
> --- a/arch/powerpc/platforms/pseries/lparcfg.c
> +++ b/arch/powerpc/platforms/pseries/lparcfg.c
> @@ -433,12 +433,12 @@ static void parse_em_data(struct seq_file *m)
>
> static void maxmem_data(struct seq_file *m)
> {
> - unsigned long maxmem = 0;
> + u64 maxmem = 0;
This is 64-bit only code, so u64 == unsigned long.
> - maxmem += drmem_info->n_lmbs * drmem_info->lmb_size;
> - maxmem += hugetlb_total_pages() * PAGE_SIZE;
> + maxmem += (u64)drmem_info->n_lmbs * drmem_info->lmb_size;
The only problem AFAICS is n_lmbs is int and lmb_size is u32, so this
multiplication will overflow.
> + maxmem += (u64)hugetlb_total_pages() * PAGE_SIZE;
hugetlb_total_pages() already returns unsigned long.
> - seq_printf(m, "MaxMem=%ld\n", maxmem);
> + seq_printf(m, "MaxMem=%llu\n", maxmem);
> }
This should be sufficient?
diff --git a/arch/powerpc/platforms/pseries/lparcfg.c b/arch/powerpc/platforms/pseries/lparcfg.c
index e33e8bc4b69b..38c306551f76 100644
--- a/arch/powerpc/platforms/pseries/lparcfg.c
+++ b/arch/powerpc/platforms/pseries/lparcfg.c
@@ -435,10 +435,10 @@ static void maxmem_data(struct seq_file *m)
{
unsigned long maxmem = 0;
- maxmem += drmem_info->n_lmbs * drmem_info->lmb_size;
+ maxmem += (unsigned long)drmem_info->n_lmbs * drmem_info->lmb_size;
maxmem += hugetlb_total_pages() * PAGE_SIZE;
- seq_printf(m, "MaxMem=%ld\n", maxmem);
+ seq_printf(m, "MaxMem=%lu\n", maxmem);
}
static int pseries_lparcfg_data(struct seq_file *m, void *v)
cheers
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH v2] Fix display of Maximum Memory
2020-01-16 5:53 ` Michael Ellerman
@ 2020-01-16 23:52 ` Michael Bringmann
0 siblings, 0 replies; 6+ messages in thread
From: Michael Bringmann @ 2020-01-16 23:52 UTC (permalink / raw)
To: Michael Ellerman, linuxppc-dev, linux-kernel, Gustavo Walbon,
Paul Mackerras
On 1/15/20 11:53 PM, Michael Ellerman wrote:
> Michael Bringmann <mwb@linux.ibm.com> writes:
>> Correct overflow problem in calculation+display of Maximum Memory
>> value to syscfg where 32bits is insufficient.
>>
>> Signed-off-by: Michael Bringmann <mwb@linux.ibm.com>
>> ---
>> arch/powerpc/platforms/pseries/lparcfg.c | 8 ++++----
>> 1 file changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/arch/powerpc/platforms/pseries/lparcfg.c b/arch/powerpc/platforms/pseries/lparcfg.c
>> index e33e8bc..f00411c 100644
>> --- a/arch/powerpc/platforms/pseries/lparcfg.c
>> +++ b/arch/powerpc/platforms/pseries/lparcfg.c
>> @@ -433,12 +433,12 @@ static void parse_em_data(struct seq_file *m)
>>
>> static void maxmem_data(struct seq_file *m)
>> {
>> - unsigned long maxmem = 0;
>> + u64 maxmem = 0;
>
> This is 64-bit only code, so u64 == unsigned long.
>
>> - maxmem += drmem_info->n_lmbs * drmem_info->lmb_size;
>> - maxmem += hugetlb_total_pages() * PAGE_SIZE;
>> + maxmem += (u64)drmem_info->n_lmbs * drmem_info->lmb_size;
>
> The only problem AFAICS is n_lmbs is int and lmb_size is u32, so this
> multiplication will overflow.
>
>> + maxmem += (u64)hugetlb_total_pages() * PAGE_SIZE;
>
> hugetlb_total_pages() already returns unsigned long.
>
>> - seq_printf(m, "MaxMem=%ld\n", maxmem);
>> + seq_printf(m, "MaxMem=%llu\n", maxmem);
>> }
>
> This should be sufficient?
>
> diff --git a/arch/powerpc/platforms/pseries/lparcfg.c b/arch/powerpc/platforms/pseries/lparcfg.c
> index e33e8bc4b69b..38c306551f76 100644
> --- a/arch/powerpc/platforms/pseries/lparcfg.c
> +++ b/arch/powerpc/platforms/pseries/lparcfg.c
> @@ -435,10 +435,10 @@ static void maxmem_data(struct seq_file *m)
> {
> unsigned long maxmem = 0;
>
> - maxmem += drmem_info->n_lmbs * drmem_info->lmb_size;
> + maxmem += (unsigned long)drmem_info->n_lmbs * drmem_info->lmb_size;
> maxmem += hugetlb_total_pages() * PAGE_SIZE;
>
> - seq_printf(m, "MaxMem=%ld\n", maxmem);
> + seq_printf(m, "MaxMem=%lu\n", maxmem);
> }
>
> static int pseries_lparcfg_data(struct seq_file *m, void *v)
>
>
> cheers
>
Trying it out.
--
Michael W. Bringmann
Linux Technology Center
IBM Corporation
Tie-Line 363-5196
External: (512) 286-5196
Cell: (512) 466-0650
mwb@linux.ibm.com
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] Fix display of Maximum Memory
2020-01-15 14:53 [PATCH v2] Fix display of Maximum Memory Michael Bringmann
` (2 preceding siblings ...)
2020-01-16 5:53 ` Michael Ellerman
@ 2020-01-29 5:17 ` Michael Ellerman
3 siblings, 0 replies; 6+ messages in thread
From: Michael Ellerman @ 2020-01-29 5:17 UTC (permalink / raw)
To: Michael Bringmann, linuxppc-dev, linux-kernel, Gustavo Walbon,
Paul Mackerras
On Wed, 2020-01-15 at 14:53:59 UTC, Michael Bringmann wrote:
> Correct overflow problem in calculation+display of Maximum Memory
> value to syscfg where 32bits is insufficient.
>
> Signed-off-by: Michael Bringmann <mwb@linux.ibm.com>
Applied to powerpc next, thanks.
https://git.kernel.org/powerpc/c/f1dbc1c5c70d0d4c60b5d467ba941fba167c12f6
cheers
^ permalink raw reply [flat|nested] 6+ messages in thread