* [PATCH] Fix isocpus's param handling when CPUMASK_OFFSTACK=n.
@ 2017-10-15 13:18 Rakib Mullick
2017-10-20 8:49 ` Ingo Molnar
0 siblings, 1 reply; 6+ messages in thread
From: Rakib Mullick @ 2017-10-15 13:18 UTC (permalink / raw)
To: peterz, mingo; +Cc: mka, longman, adobriyan, tglx, akpm, tj, linux-kernel
cpulist_parse() uses nr_cpumask_bits as limit to parse the
passed buffer from kernel commandline. What nr_cpumask_bits
represents varies depends upon CONFIG_CPUMASK_OFFSTACK option.
If CONFIG_CPUMASK_OFFSTACK=n, then nr_cpumask_bits is same as
NR_CPUS, which might not represent the # of cpus really exist
(default 64). So, there's a chance of gap between nr_cpu_ids
and NR_CPUS, which ultimately lead towards invalid cpulist_parse()
operation. For example, if isolcpus=9 is passed on a 8 cpu
system (CONFIG_CPUMASK_OFFSTACK=n) it doesn't show the error
that it suppose to.
This patch fixes this issue by effectively find out the last
cpu of the passed isolcpus list and checking it with nr_cpu_ids.
Also, fixes the error message where the nr_cpu_ids should be
nr_cpu_ids-1, since the cpu numbering starts from 0.
Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
---
include/linux/cpumask.h | 16 ++++++++++++++++
kernel/sched/topology.c | 8 +++++---
2 files changed, 21 insertions(+), 3 deletions(-)
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index 2404ad2..f9a7c9b 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -130,6 +130,11 @@ static inline unsigned int cpumask_first(const struct cpumask *srcp)
return 0;
}
+static inline unsigned int cpumask_last(const struct cpumask *srcp)
+{
+ return 0;
+}
+
/* Valid inputs for n are -1 and 0. */
static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
{
@@ -179,6 +184,17 @@ static inline unsigned int cpumask_first(const struct cpumask *srcp)
}
/**
+ * cpumask_last - get the last cpu in a cpumask
+ * @srcp: - the cpumask pointer
+ *
+ * Returns >= nr_cpumask_bits if no cpus set.
+ */
+static inline unsigned int cpumask_last(const struct cpumask *srcp)
+{
+ return find_last_bit(cpumask_bits(srcp), nr_cpumask_bits);
+}
+
+/**
* cpumask_next - get the next cpu in a cpumask
* @n: the cpu prior to the place to search (ie. return will be > @n)
* @srcp: the cpumask pointer
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index 1b0b4fb..55b5e09 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -452,12 +452,14 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
/* Setup the mask of CPUs configured for isolated domains */
static int __init isolated_cpu_setup(char *str)
{
- int ret;
+ int ret, lastcpu;
alloc_bootmem_cpumask_var(&cpu_isolated_map);
ret = cpulist_parse(str, cpu_isolated_map);
- if (ret) {
- pr_err("sched: Error, all isolcpus= values must be between 0 and %d\n", nr_cpu_ids);
+ lastcpu = cpumask_last(cpu_isolated_map);
+ if (ret || lastcpu >= nr_cpu_ids) {
+ pr_err("sched: Error, all isolcpus= values must be between 0 and %d\n",
+ nr_cpu_ids-1);
return 0;
}
return 1;
--
2.9.3
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH] Fix isocpus's param handling when CPUMASK_OFFSTACK=n.
2017-10-15 13:18 [PATCH] Fix isocpus's param handling when CPUMASK_OFFSTACK=n Rakib Mullick
@ 2017-10-20 8:49 ` Ingo Molnar
2017-10-21 7:10 ` Rakib Mullick
0 siblings, 1 reply; 6+ messages in thread
From: Ingo Molnar @ 2017-10-20 8:49 UTC (permalink / raw)
To: Rakib Mullick
Cc: peterz, mka, longman, adobriyan, tglx, akpm, tj, linux-kernel
* Rakib Mullick <rakib.mullick@gmail.com> wrote:
> cpulist_parse() uses nr_cpumask_bits as limit to parse the
> passed buffer from kernel commandline. What nr_cpumask_bits
> represents varies depends upon CONFIG_CPUMASK_OFFSTACK option.
> If CONFIG_CPUMASK_OFFSTACK=n, then nr_cpumask_bits is same as
> NR_CPUS, which might not represent the # of cpus really exist
> (default 64). So, there's a chance of gap between nr_cpu_ids
> and NR_CPUS, which ultimately lead towards invalid cpulist_parse()
> operation. For example, if isolcpus=9 is passed on a 8 cpu
> system (CONFIG_CPUMASK_OFFSTACK=n) it doesn't show the error
> that it suppose to.
>
> This patch fixes this issue by effectively find out the last
> cpu of the passed isolcpus list and checking it with nr_cpu_ids.
> Also, fixes the error message where the nr_cpu_ids should be
> nr_cpu_ids-1, since the cpu numbering starts from 0.
>
> Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
> ---
> include/linux/cpumask.h | 16 ++++++++++++++++
> kernel/sched/topology.c | 8 +++++---
> 2 files changed, 21 insertions(+), 3 deletions(-)
What kernel is this against? It does not apply to the latest kernels.
Thanks,
Ingo
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH] Fix isocpus's param handling when CPUMASK_OFFSTACK=n.
2017-10-20 8:49 ` Ingo Molnar
@ 2017-10-21 7:10 ` Rakib Mullick
2017-10-23 11:50 ` Ingo Molnar
0 siblings, 1 reply; 6+ messages in thread
From: Rakib Mullick @ 2017-10-21 7:10 UTC (permalink / raw)
To: mingo; +Cc: peterz, mka, longman, adobriyan, tglx, akpm, tj, linux-kernel
> *On Fri, Oct 20, 2017 at 2:49 PM, Ingo Molnar <mingo@kernel.org> wrote:
>
>> Rakib Mullick <rakib.mullick@gmail.com> wrote:
>> include/linux/cpumask.h | 16 ++++++++++++++++
>> kernel/sched/topology.c | 8 +++++---
>> 2 files changed, 21 insertions(+), 3 deletions(-)
>
> What kernel is this against? It does not apply to the latest kernels.
It was against 4.14-rc4, prepared before -rc5 release. Please, consider
the below one, against -rc5.
cpulist_parse() uses nr_cpumask_bits as limit to parse the
passed buffer from kernel commandline. What nr_cpumask_bits
represents varies depends upon CONFIG_CPUMASK_OFFSTACK option.
If CONFIG_CPUMASK_OFFSTACK=n, then nr_cpumask_bits is same as
NR_CPUS, which might not represent the # of cpus really exist
(default 64). So, there's a chance of gap between nr_cpu_ids
and NR_CPUS, which ultimately lead towards invalid cpulist_parse()
operation. For example, if isolcpus=9 is passed on a 8 cpu
system (CONFIG_CPUMASK_OFFSTACK=n) it doesn't show the error
that it suppose to.
This patch fixes this issue by effectively find out the last
cpu of the passed isolcpus list and checking it with nr_cpu_ids.
Also, fixes the error message where the nr_cpu_ids should be
nr_cpu_ids-1, since the cpu numbering starts from 0.
Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
---
include/linux/cpumask.h | 16 ++++++++++++++++
kernel/sched/topology.c | 8 +++++---
2 files changed, 21 insertions(+), 3 deletions(-)
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index cd415b7..5631725 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -130,6 +130,11 @@ static inline unsigned int cpumask_first(const struct cpumask *srcp)
return 0;
}
+static inline unsigned int cpumask_last(const struct cpumask *srcp)
+{
+ return 0;
+}
+
/* Valid inputs for n are -1 and 0. */
static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
{
@@ -178,6 +183,17 @@ static inline unsigned int cpumask_first(const struct cpumask *srcp)
return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits);
}
+/**
+ * cpumask_last - get the last cpu in a cpumask
+ * @srcp: - the cpumask pointer
+ *
+ * Returns >= nr_cpumask_bits if no cpus set.
+ */
+static inline unsigned int cpumask_last(const struct cpumask *srcp)
+{
+ return find_last_bit(cpumask_bits(srcp), nr_cpumask_bits);
+}
+
unsigned int cpumask_next(int n, const struct cpumask *srcp);
/**
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index f1cf4f3..b9265c8 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -466,12 +466,14 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
/* Setup the mask of CPUs configured for isolated domains */
static int __init isolated_cpu_setup(char *str)
{
- int ret;
+ int ret, lastcpu;
alloc_bootmem_cpumask_var(&cpu_isolated_map);
ret = cpulist_parse(str, cpu_isolated_map);
- if (ret) {
- pr_err("sched: Error, all isolcpus= values must be between 0 and %u\n", nr_cpu_ids);
+ lastcpu = cpumask_last(cpu_isolated_map);
+ if (ret || lastcpu >= nr_cpu_ids) {
+ pr_err("sched: Error, all isolcpus= values must be between 0 and %u\n",
+ nr_cpu_ids-1);
return 0;
}
return 1;
--
2.9.3
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH] Fix isocpus's param handling when CPUMASK_OFFSTACK=n.
2017-10-21 7:10 ` Rakib Mullick
@ 2017-10-23 11:50 ` Ingo Molnar
2017-10-23 13:01 ` Rakib Mullick
0 siblings, 1 reply; 6+ messages in thread
From: Ingo Molnar @ 2017-10-23 11:50 UTC (permalink / raw)
To: Rakib Mullick
Cc: peterz, mka, longman, adobriyan, tglx, akpm, tj, linux-kernel
* Rakib Mullick <rakib.mullick@gmail.com> wrote:
> > *On Fri, Oct 20, 2017 at 2:49 PM, Ingo Molnar <mingo@kernel.org> wrote:
> >
> >> Rakib Mullick <rakib.mullick@gmail.com> wrote:
> >> include/linux/cpumask.h | 16 ++++++++++++++++
> >> kernel/sched/topology.c | 8 +++++---
> >> 2 files changed, 21 insertions(+), 3 deletions(-)
> >
> > What kernel is this against? It does not apply to the latest kernels.
>
> It was against 4.14-rc4, prepared before -rc5 release. Please, consider
> the below one, against -rc5.
>
> cpulist_parse() uses nr_cpumask_bits as limit to parse the
> passed buffer from kernel commandline. What nr_cpumask_bits
> represents varies depends upon CONFIG_CPUMASK_OFFSTACK option.
> If CONFIG_CPUMASK_OFFSTACK=n, then nr_cpumask_bits is same as
> NR_CPUS, which might not represent the # of cpus really exist
> (default 64). So, there's a chance of gap between nr_cpu_ids
> and NR_CPUS, which ultimately lead towards invalid cpulist_parse()
> operation. For example, if isolcpus=9 is passed on a 8 cpu
> system (CONFIG_CPUMASK_OFFSTACK=n) it doesn't show the error
> that it suppose to.
>
> This patch fixes this issue by effectively find out the last
> cpu of the passed isolcpus list and checking it with nr_cpu_ids.
> Also, fixes the error message where the nr_cpu_ids should be
> nr_cpu_ids-1, since the cpu numbering starts from 0.
>
> Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
> ---
> include/linux/cpumask.h | 16 ++++++++++++++++
> kernel/sched/topology.c | 8 +++++---
> 2 files changed, 21 insertions(+), 3 deletions(-)
>
> diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
> index cd415b7..5631725 100644
> --- a/include/linux/cpumask.h
> +++ b/include/linux/cpumask.h
> @@ -130,6 +130,11 @@ static inline unsigned int cpumask_first(const struct cpumask *srcp)
> return 0;
> }
>
> +static inline unsigned int cpumask_last(const struct cpumask *srcp)
> +{
> + return 0;
> +}
> +
> /* Valid inputs for n are -1 and 0. */
> static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
> {
> @@ -178,6 +183,17 @@ static inline unsigned int cpumask_first(const struct cpumask *srcp)
> return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits);
> }
>
> +/**
> + * cpumask_last - get the last cpu in a cpumask
Please capitalize 'CPU' properly in documentation.
> + * @srcp: - the cpumask pointer
> + *
> + * Returns >= nr_cpumask_bits if no cpus set.
> + */
> +static inline unsigned int cpumask_last(const struct cpumask *srcp)
> +{
> + return find_last_bit(cpumask_bits(srcp), nr_cpumask_bits);
> +}
> +
> unsigned int cpumask_next(int n, const struct cpumask *srcp);
>
> /**
> diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
> index f1cf4f3..b9265c8 100644
> --- a/kernel/sched/topology.c
> +++ b/kernel/sched/topology.c
> @@ -466,12 +466,14 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
> /* Setup the mask of CPUs configured for isolated domains */
> static int __init isolated_cpu_setup(char *str)
> {
> - int ret;
> + int ret, lastcpu;
>
> alloc_bootmem_cpumask_var(&cpu_isolated_map);
> ret = cpulist_parse(str, cpu_isolated_map);
> - if (ret) {
> - pr_err("sched: Error, all isolcpus= values must be between 0 and %u\n", nr_cpu_ids);
> + lastcpu = cpumask_last(cpu_isolated_map);
> + if (ret || lastcpu >= nr_cpu_ids) {
Any reason why 'lastcpu' has to be introduced - why not just use cpumask_last()
directly in the condition? It looks obvious enough of a pattern.
> + pr_err("sched: Error, all isolcpus= values must be between 0 and %u\n",
> + nr_cpu_ids-1);
Please don't break the line mindlessly just due to checkpatch complaining - it
makes the code less readable.
Thanks,
Ingo
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH] Fix isocpus's param handling when CPUMASK_OFFSTACK=n.
2017-10-23 11:50 ` Ingo Molnar
@ 2017-10-23 13:01 ` Rakib Mullick
2017-10-24 10:17 ` [tip:sched/core] sched/isolcpus: Fix "isolcpus=" boot parameter handling when !CONFIG_CPUMASK_OFFSTACK tip-bot for Rakib Mullick
0 siblings, 1 reply; 6+ messages in thread
From: Rakib Mullick @ 2017-10-23 13:01 UTC (permalink / raw)
To: mingo; +Cc: peterz, mka, longman, adobriyan, tglx, akpm, tj, linux-kernel
> On Mon, Oct 23, 2017 at 5:50 PM, Ingo Molnar <mingo@kernel.org> wrote:
>
>> * Rakib Mullick <rakib.mullick@gmail.com> wrote:
>> +/**
>> + * cpumask_last - get the last cpu in a cpumask
>
> Please capitalize 'CPU' properly in documentation.
>
OK.
>> + int ret, lastcpu;
>>
>> alloc_bootmem_cpumask_var(&cpu_isolated_map);
>> ret = cpulist_parse(str, cpu_isolated_map);
>> - if (ret) {
>> - pr_err("sched: Error, all isolcpus= values must be between 0 and %u\n", nr_cpu_ids);
>> + lastcpu = cpumask_last(cpu_isolated_map);
>> + if (ret || lastcpu >= nr_cpu_ids) {
>
> Any reason why 'lastcpu' has to be introduced - why not just use cpumask_last()
> directly in the condition? It looks obvious enough of a pattern.
Thought it reflects what we're doing here, but yes, actually it's redundant.
>> + pr_err("sched: Error, all isolcpus= values must be between 0 and %u\n",
>> + nr_cpu_ids-1);
>
> Please don't break the line mindlessly just due to checkpatch complaining - it
> makes the code less readable.
>
Yes, right, mindlessly followed what checkpatch was complaining.
Please see the following patch, with changes made based on your review and
patched up against -rc6.
Thanks,
Rakib
---
[PATCH](v1) Fix isocpus's param handling when CPUMASK_OFFSTACK=n.
cpulist_parse() uses nr_cpumask_bits as limit to parse the
passed buffer from kernel commandline. What nr_cpumask_bits
represents varies depends upon CONFIG_CPUMASK_OFFSTACK option.
If CONFIG_CPUMASK_OFFSTACK=n, then nr_cpumask_bits is same as
NR_CPUS, which might not represent the # of cpus really exist
(default 64). So, there's a chance of gap between nr_cpu_ids
and NR_CPUS, which ultimately lead towards invalid cpulist_parse()
operation. For example, if isolcpus=9 is passed on a 8 cpu
system (CONFIG_CPUMASK_OFFSTACK=n) it doesn't show the error
that it suppose to.
This patch fixes this issue by effectively find out the last
cpu of the passed isolcpus list and checking it with nr_cpu_ids.
Also, fixes the error message where the nr_cpu_ids should be
nr_cpu_ids-1, since the cpu numbering starts from 0.
Changes since v0 (Ingo):
* use cpumask_last() directly into the condition.
* use CPU rather cpu in documentation
* undo line break
Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
---
include/linux/cpumask.h | 16 ++++++++++++++++
kernel/sched/topology.c | 4 ++--
2 files changed, 18 insertions(+), 2 deletions(-)
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index cd415b7..63661de 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -130,6 +130,11 @@ static inline unsigned int cpumask_first(const struct cpumask *srcp)
return 0;
}
+static inline unsigned int cpumask_last(const struct cpumask *srcp)
+{
+ return 0;
+}
+
/* Valid inputs for n are -1 and 0. */
static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
{
@@ -178,6 +183,17 @@ static inline unsigned int cpumask_first(const struct cpumask *srcp)
return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits);
}
+/**
+ * cpumask_last - get the last CPU in a cpumask
+ * @srcp: - the cpumask pointer
+ *
+ * Returns >= nr_cpumask_bits if no CPUs set.
+ */
+static inline unsigned int cpumask_last(const struct cpumask *srcp)
+{
+ return find_last_bit(cpumask_bits(srcp), nr_cpumask_bits);
+}
+
unsigned int cpumask_next(int n, const struct cpumask *srcp);
/**
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index f1cf4f3..060cee5 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -470,8 +470,8 @@ static int __init isolated_cpu_setup(char *str)
alloc_bootmem_cpumask_var(&cpu_isolated_map);
ret = cpulist_parse(str, cpu_isolated_map);
- if (ret) {
- pr_err("sched: Error, all isolcpus= values must be between 0 and %u\n", nr_cpu_ids);
+ if (ret || cpumask_last(cpu_isolated_map) >= nr_cpu_ids) {
+ pr_err("sched: Error, all isolcpus= values must be between 0 and %u\n", nr_cpu_ids-1);
return 0;
}
return 1;
--
2.9.3
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [tip:sched/core] sched/isolcpus: Fix "isolcpus=" boot parameter handling when !CONFIG_CPUMASK_OFFSTACK
2017-10-23 13:01 ` Rakib Mullick
@ 2017-10-24 10:17 ` tip-bot for Rakib Mullick
0 siblings, 0 replies; 6+ messages in thread
From: tip-bot for Rakib Mullick @ 2017-10-24 10:17 UTC (permalink / raw)
To: linux-tip-commits
Cc: mingo, rakib.mullick, linux-kernel, peterz, tglx, torvalds, hpa
Commit-ID: e22cdc3fc5991956146b9856d36b4971fe54dcd6
Gitweb: https://git.kernel.org/tip/e22cdc3fc5991956146b9856d36b4971fe54dcd6
Author: Rakib Mullick <rakib.mullick@gmail.com>
AuthorDate: Mon, 23 Oct 2017 19:01:54 +0600
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Tue, 24 Oct 2017 11:47:25 +0200
sched/isolcpus: Fix "isolcpus=" boot parameter handling when !CONFIG_CPUMASK_OFFSTACK
cpulist_parse() uses nr_cpumask_bits as a limit to parse the
passed buffer from kernel commandline. What nr_cpumask_bits
represents varies depending upon the CONFIG_CPUMASK_OFFSTACK option:
- If CONFIG_CPUMASK_OFFSTACK=n, then nr_cpumask_bits is the same as
NR_CPUS, which might not represent the # of CPUs that really exist
(default 64). So, there's a chance of a gap between nr_cpu_ids
and NR_CPUS, which ultimately lead towards invalid cpulist_parse()
operation. For example, if isolcpus=9 is passed on an 8 cpu
system (CONFIG_CPUMASK_OFFSTACK=n) it doesn't show the error
that it's supposed to.
This patch fixes this bug by finding the last CPU of the passed
isolcpus= list and checking it against nr_cpu_ids.
It also fixes the error message where the nr_cpu_ids should be
nr_cpu_ids-1, since CPU numbering starts from 0.
Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: adobriyan@gmail.com
Cc: akpm@linux-foundation.org
Cc: longman@redhat.com
Cc: mka@chromium.org
Cc: tj@kernel.org
Link: http://lkml.kernel.org/r/20171023130154.9050-1-rakib.mullick@gmail.com
[ Enhanced the changelog and the kernel message. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
include/linux/cpumask.h | 16 ++++++++++++++++
kernel/sched/topology.c | 4 ++--
2 files changed, 18 insertions(+), 2 deletions(-)
---
include/linux/cpumask.h | 16 ++++++++++++++++
kernel/sched/topology.c | 4 ++--
2 files changed, 18 insertions(+), 2 deletions(-)
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index cd415b7..63661de 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -130,6 +130,11 @@ static inline unsigned int cpumask_first(const struct cpumask *srcp)
return 0;
}
+static inline unsigned int cpumask_last(const struct cpumask *srcp)
+{
+ return 0;
+}
+
/* Valid inputs for n are -1 and 0. */
static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
{
@@ -178,6 +183,17 @@ static inline unsigned int cpumask_first(const struct cpumask *srcp)
return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits);
}
+/**
+ * cpumask_last - get the last CPU in a cpumask
+ * @srcp: - the cpumask pointer
+ *
+ * Returns >= nr_cpumask_bits if no CPUs set.
+ */
+static inline unsigned int cpumask_last(const struct cpumask *srcp)
+{
+ return find_last_bit(cpumask_bits(srcp), nr_cpumask_bits);
+}
+
unsigned int cpumask_next(int n, const struct cpumask *srcp);
/**
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index e50450c..e3d31b0 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -476,8 +476,8 @@ static int __init isolated_cpu_setup(char *str)
alloc_bootmem_cpumask_var(&cpu_isolated_map);
ret = cpulist_parse(str, cpu_isolated_map);
- if (ret) {
- pr_err("sched: Error, all isolcpus= values must be between 0 and %u\n", nr_cpu_ids);
+ if (ret || cpumask_last(cpu_isolated_map) >= nr_cpu_ids) {
+ pr_err("sched: Error, all isolcpus= values must be between 0 and %u - ignoring them.\n", nr_cpu_ids-1);
return 0;
}
return 1;
^ permalink raw reply related [flat|nested] 6+ messages in thread
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2017-10-15 13:18 [PATCH] Fix isocpus's param handling when CPUMASK_OFFSTACK=n Rakib Mullick
2017-10-20 8:49 ` Ingo Molnar
2017-10-21 7:10 ` Rakib Mullick
2017-10-23 11:50 ` Ingo Molnar
2017-10-23 13:01 ` Rakib Mullick
2017-10-24 10:17 ` [tip:sched/core] sched/isolcpus: Fix "isolcpus=" boot parameter handling when !CONFIG_CPUMASK_OFFSTACK tip-bot for Rakib Mullick
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