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[RFC][PATCH] x86/smp: Fix __max_logical_packages value setup

Started byJiri Olsa <jolsa@redhat.com>
First post2016-08-03 18:30 +0200
Last post2016-08-10 22:40 +0200
Articles 7 — 2 participants

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  [RFC][PATCH] x86/smp: Fix __max_logical_packages value setup Jiri Olsa <jolsa@redhat.com> - 2016-08-03 18:30 +0200
    Re: [RFC][PATCH] x86/smp: Fix __max_logical_packages value setup Jiri Olsa <jolsa@redhat.com> - 2016-08-10 20:50 +0200
      [PATCH] x86/smp: Fix __max_logical_packages value setup Jiri Olsa <jolsa@redhat.com> - 2016-08-10 20:50 +0200
      Re: [RFC][PATCH] x86/smp: Fix __max_logical_packages value setup Jiri Olsa <jolsa@redhat.com> - 2016-08-10 21:10 +0200
        Re: [RFC][PATCH] x86/smp: Fix __max_logical_packages value setup Peter Zijlstra <peterz@infradead.org> - 2016-08-10 21:20 +0200
    Re: [RFC][PATCH] x86/smp: Fix __max_logical_packages value setup Peter Zijlstra <peterz@infradead.org> - 2016-08-10 21:20 +0200
    Re: [RFC][PATCH] x86/smp: Fix __max_logical_packages value setup Jiri Olsa <jolsa@redhat.com> - 2016-08-10 22:40 +0200

#1455885 — [RFC][PATCH] x86/smp: Fix __max_logical_packages value setup

FromJiri Olsa <jolsa@redhat.com>
Date2016-08-03 18:30 +0200
Subject[RFC][PATCH] x86/smp: Fix __max_logical_packages value setup
Message-ID<s27do-4Ot-27@gated-at.bofh.it>
Frank reported kernel panic when he disabled several cores in BIOS
via following option:

  Core Disable Bitmap(Hex)   [0]

with number 0xFFE, which leaves 16 CPUs in system (out of 48).

The kernel panic below goes along with following messages:

 smpboot: Max logical packages: 2^M
 smpboot: APIC(0) Converting physical 0 to logical package 0^M
 smpboot: APIC(20) Converting physical 1 to logical package 1^M
 smpboot: APIC(40) Package 2 exceeds logical package map^M
 smpboot: CPU 8 APICId 40 disabled^M
 smpboot: APIC(60) Package 3 exceeds logical package map^M
 smpboot: CPU 12 APICId 60 disabled^M
 ...
 general protection fault: 0000 [#1] SMP^M
 Modules linked in:^M
 CPU: 15 PID: 1 Comm: swapper/0 Not tainted 4.7.0-rc5+ #1^M
 Hardware name: SGI UV300/UV300, BIOS SGI UV 300 series BIOS 05/25/2016^M
 task: ffff8801673e0000 ti: ffff8801673ac000 task.ti: ffff8801673ac000^M
 RIP: 0010:[<ffffffff81014d54>]  [<ffffffff81014d54>] uncore_change_context+0xd4/0x180^M
 ...
  [<ffffffff810158ac>] uncore_event_init_cpu+0x6c/0x70^M
  [<ffffffff81d8c91c>] intel_uncore_init+0x1c2/0x2dd^M
  [<ffffffff81d8c75a>] ? uncore_cpu_setup+0x17/0x17^M
  [<ffffffff81002190>] do_one_initcall+0x50/0x190^M
  [<ffffffff810ab193>] ? parse_args+0x293/0x480^M
  [<ffffffff81d87365>] kernel_init_freeable+0x1a5/0x249^M
  [<ffffffff81d86a35>] ? set_debug_rodata+0x12/0x12^M
  [<ffffffff816dc19e>] kernel_init+0xe/0x110^M
  [<ffffffff816e93bf>] ret_from_fork+0x1f/0x40^M
  [<ffffffff816dc190>] ? rest_init+0x80/0x80^M

The reason for the panic is wrong value of __max_logical_packages,
which lets logical_package_map uninitialized and the uncore code
relying on this map being properly initialized (maybe we should
add some safety checks there as well).

The __max_logical_packages is computed as:

  DIV_ROUND_UP(total_cpus, ncpus);
  - ncpus being number of cores

With above BIOS setup we get total_cpus == 16 which set
__max_logical_packages to 2 (ncpus is 12). 

Once topology_update_package_map processes CPU with logical
pkg over 2 we display above messages and fail to initialize
the physical_to_logical_pkg map, which makes the uncore code
crash.

The fix is to set __max_logical_packages directly to total_cpus,
which should be the maximum possible logical ID of the pkg in
any case.

Reported-by: Frank Ramsay <framsay@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 157bf0957219..484f7d357c77 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -340,7 +340,7 @@ static void __init smp_init_package_map(void)
 		ncpus = 1;
 	}
 
-	__max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus);
+	__max_logical_packages = total_cpus;
 
 	/*
 	 * Possibly larger than what we need as the number of apic ids per

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#1459494

FromJiri Olsa <jolsa@redhat.com>
Date2016-08-10 20:50 +0200
Message-ID<s4GJH-j6-15@gated-at.bofh.it>
In reply to#1455885
On Wed, Aug 10, 2016 at 03:54:17PM +0200, Peter Zijlstra wrote:
> On Wed, Aug 03, 2016 at 06:23:58PM +0200, Jiri Olsa wrote:

SNIP

> > ---
> > diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
> > index 157bf0957219..484f7d357c77 100644
> > --- a/arch/x86/kernel/smpboot.c
> > +++ b/arch/x86/kernel/smpboot.c
> > @@ -340,7 +340,7 @@ static void __init smp_init_package_map(void)
> >  		ncpus = 1;
> >  	}
> >  
> > -	__max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus);
> > +	__max_logical_packages = total_cpus;
> 
> This seems undesirable.. it would grow the bitmap unnecessarily big on
> most setups.
> 
> Is there no way to detect the brain damage inflicted by that BIOS option
> and fudge ncpus in that case?

yea, I have no idea.. that's why this is RFC ;-)

maybe we could also gradually allocate this bitmap
in topology_update_package_map.. I'll check on that

jirka

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#1459495 — [PATCH] x86/smp: Fix __max_logical_packages value setup

FromJiri Olsa <jolsa@redhat.com>
Date2016-08-10 20:50 +0200
Subject[PATCH] x86/smp: Fix __max_logical_packages value setup
Message-ID<s4GJH-j6-11@gated-at.bofh.it>
In reply to#1459494
On Wed, Aug 10, 2016 at 05:52:05PM +0200, Peter Zijlstra wrote:
> On Wed, Aug 10, 2016 at 04:15:38PM +0200, Jiri Olsa wrote:
> > it's very likely I'm missing something, but seems to me
> > that attached patch (untested) might work as well
> 
> Hmm, I think you're right. Earlier code (which hasn't survived) tried to
> match logical and physical if possible, but that was busted and got
> removed.
> 
> The code as is should indeed allow for this.
> 
> Maybe one nit, the variable is no longer used for a max, so maybe rename
> it too?

ok, renaming it to logical_packages then, attaching full patch

thanks,
jirka


---
Frank reported kernel panic when he disabled several cores in BIOS
via following option:

  Core Disable Bitmap(Hex)   [0]

with number 0xFFE, which leaves 16 CPUs in system (out of 48).

The kernel panic below goes along with following messages:

 smpboot: Max logical packages: 2^M
 smpboot: APIC(0) Converting physical 0 to logical package 0^M
 smpboot: APIC(20) Converting physical 1 to logical package 1^M
 smpboot: APIC(40) Package 2 exceeds logical package map^M
 smpboot: CPU 8 APICId 40 disabled^M
 smpboot: APIC(60) Package 3 exceeds logical package map^M
 smpboot: CPU 12 APICId 60 disabled^M
 ...
 general protection fault: 0000 [#1] SMP^M
 Modules linked in:^M
 CPU: 15 PID: 1 Comm: swapper/0 Not tainted 4.7.0-rc5+ #1^M
 Hardware name: SGI UV300/UV300, BIOS SGI UV 300 series BIOS 05/25/2016^M
 task: ffff8801673e0000 ti: ffff8801673ac000 task.ti: ffff8801673ac000^M
 RIP: 0010:[<ffffffff81014d54>]  [<ffffffff81014d54>] uncore_change_context+0xd4/0x180^M
 ...
  [<ffffffff810158ac>] uncore_event_init_cpu+0x6c/0x70^M
  [<ffffffff81d8c91c>] intel_uncore_init+0x1c2/0x2dd^M
  [<ffffffff81d8c75a>] ? uncore_cpu_setup+0x17/0x17^M
  [<ffffffff81002190>] do_one_initcall+0x50/0x190^M
  [<ffffffff810ab193>] ? parse_args+0x293/0x480^M
  [<ffffffff81d87365>] kernel_init_freeable+0x1a5/0x249^M
  [<ffffffff81d86a35>] ? set_debug_rodata+0x12/0x12^M
  [<ffffffff816dc19e>] kernel_init+0xe/0x110^M
  [<ffffffff816e93bf>] ret_from_fork+0x1f/0x40^M
  [<ffffffff816dc190>] ? rest_init+0x80/0x80^M

The reason for the panic is wrong value of __max_logical_packages,
which lets logical_package_map uninitialized and the uncore code
relying on this map being properly initialized (maybe we should
add some safety checks there as well).

The __max_logical_packages is computed as:

  DIV_ROUND_UP(total_cpus, ncpus);
  - ncpus being number of cores

With above BIOS setup we get total_cpus == 16 which set
__max_logical_packages to 2 (ncpus is 12).

Once topology_update_package_map processes CPU with logical
pkg over 2 we display above messages and fail to initialize
the physical_to_logical_pkg map, which makes the uncore code
crash.

The fix is to remove logical_package_map bitmap completely
and just keep and update the logical_packages number.

Reported-by: Frank Ramsay <framsay@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 arch/x86/include/asm/topology.h |  4 ++--
 arch/x86/kernel/smpboot.c       | 21 +++++----------------
 2 files changed, 7 insertions(+), 18 deletions(-)

diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index cf75871d2f81..c28010088651 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -118,8 +118,8 @@ extern const struct cpumask *cpu_coregroup_mask(int cpu);
 #define topology_core_cpumask(cpu)		(per_cpu(cpu_core_map, cpu))
 #define topology_sibling_cpumask(cpu)		(per_cpu(cpu_sibling_map, cpu))
 
-extern unsigned int __max_logical_packages;
-#define topology_max_packages()			(__max_logical_packages)
+extern unsigned int logical_packages;
+#define topology_max_packages()			(logical_packages)
 
 extern int __max_smt_threads;
 
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 157bf0957219..b1b775dbede6 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -100,10 +100,9 @@ EXPORT_PER_CPU_SYMBOL(cpu_info);
 /* Logical package management. We might want to allocate that dynamically */
 static int *physical_to_logical_pkg __read_mostly;
 static unsigned long *physical_package_map __read_mostly;;
-static unsigned long *logical_package_map  __read_mostly;
 static unsigned int max_physical_pkg_id __read_mostly;
-unsigned int __max_logical_packages __read_mostly;
-EXPORT_SYMBOL(__max_logical_packages);
+unsigned int logical_packages __read_mostly;
+EXPORT_SYMBOL(logical_packages);
 
 /* Maximum number of SMT threads on any online core */
 int __max_smt_threads __read_mostly;
@@ -277,14 +276,8 @@ int topology_update_package_map(unsigned int apicid, unsigned int cpu)
 	if (test_and_set_bit(pkg, physical_package_map))
 		goto found;
 
-	new = find_first_zero_bit(logical_package_map, __max_logical_packages);
-	if (new >= __max_logical_packages) {
-		physical_to_logical_pkg[pkg] = -1;
-		pr_warn("APIC(%x) Package %u exceeds logical package map\n",
-			apicid, pkg);
-		return -ENOSPC;
-	}
-	set_bit(new, logical_package_map);
+	new = logical_packages++;
+
 	pr_info("APIC(%x) Converting physical %u to logical package %u\n",
 		apicid, pkg, new);
 	physical_to_logical_pkg[pkg] = new;
@@ -340,7 +333,7 @@ static void __init smp_init_package_map(void)
 		ncpus = 1;
 	}
 
-	__max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus);
+	logical_packages = 0;
 
 	/*
 	 * Possibly larger than what we need as the number of apic ids per
@@ -352,10 +345,6 @@ static void __init smp_init_package_map(void)
 	memset(physical_to_logical_pkg, 0xff, size);
 	size = BITS_TO_LONGS(max_physical_pkg_id) * sizeof(unsigned long);
 	physical_package_map = kzalloc(size, GFP_KERNEL);
-	size = BITS_TO_LONGS(__max_logical_packages) * sizeof(unsigned long);
-	logical_package_map = kzalloc(size, GFP_KERNEL);
-
-	pr_info("Max logical packages: %u\n", __max_logical_packages);
 
 	for_each_present_cpu(cpu) {
 		unsigned int apicid = apic->cpu_present_to_apicid(cpu);
-- 
2.4.11

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#1459588

FromJiri Olsa <jolsa@redhat.com>
Date2016-08-10 21:10 +0200
Message-ID<s4GJH-j6-17@gated-at.bofh.it>
In reply to#1459494
On Wed, Aug 10, 2016 at 04:00:33PM +0200, Jiri Olsa wrote:
> On Wed, Aug 10, 2016 at 03:54:17PM +0200, Peter Zijlstra wrote:
> > On Wed, Aug 03, 2016 at 06:23:58PM +0200, Jiri Olsa wrote:
> 
> SNIP
> 
> > > ---
> > > diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
> > > index 157bf0957219..484f7d357c77 100644
> > > --- a/arch/x86/kernel/smpboot.c
> > > +++ b/arch/x86/kernel/smpboot.c
> > > @@ -340,7 +340,7 @@ static void __init smp_init_package_map(void)
> > >  		ncpus = 1;
> > >  	}
> > >  
> > > -	__max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus);
> > > +	__max_logical_packages = total_cpus;
> > 
> > This seems undesirable.. it would grow the bitmap unnecessarily big on
> > most setups.
> > 
> > Is there no way to detect the brain damage inflicted by that BIOS option
> > and fudge ncpus in that case?
> 
> yea, I have no idea.. that's why this is RFC ;-)
> 
> maybe we could also gradually allocate this bitmap
> in topology_update_package_map.. I'll check on that

it's very likely I'm missing something, but seems to me
that attached patch (untested) might work as well

jirka


---
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 157bf0957219..003208bc8e44 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -100,7 +100,6 @@ EXPORT_PER_CPU_SYMBOL(cpu_info);
 /* Logical package management. We might want to allocate that dynamically */
 static int *physical_to_logical_pkg __read_mostly;
 static unsigned long *physical_package_map __read_mostly;;
-static unsigned long *logical_package_map  __read_mostly;
 static unsigned int max_physical_pkg_id __read_mostly;
 unsigned int __max_logical_packages __read_mostly;
 EXPORT_SYMBOL(__max_logical_packages);
@@ -277,14 +276,8 @@ int topology_update_package_map(unsigned int apicid, unsigned int cpu)
 	if (test_and_set_bit(pkg, physical_package_map))
 		goto found;
 
-	new = find_first_zero_bit(logical_package_map, __max_logical_packages);
-	if (new >= __max_logical_packages) {
-		physical_to_logical_pkg[pkg] = -1;
-		pr_warn("APIC(%x) Package %u exceeds logical package map\n",
-			apicid, pkg);
-		return -ENOSPC;
-	}
-	set_bit(new, logical_package_map);
+	new = __max_logical_packages++;
+
 	pr_info("APIC(%x) Converting physical %u to logical package %u\n",
 		apicid, pkg, new);
 	physical_to_logical_pkg[pkg] = new;
@@ -340,7 +333,7 @@ static void __init smp_init_package_map(void)
 		ncpus = 1;
 	}
 
-	__max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus);
+	__max_logical_packages = 0;
 
 	/*
 	 * Possibly larger than what we need as the number of apic ids per
@@ -352,10 +345,6 @@ static void __init smp_init_package_map(void)
 	memset(physical_to_logical_pkg, 0xff, size);
 	size = BITS_TO_LONGS(max_physical_pkg_id) * sizeof(unsigned long);
 	physical_package_map = kzalloc(size, GFP_KERNEL);
-	size = BITS_TO_LONGS(__max_logical_packages) * sizeof(unsigned long);
-	logical_package_map = kzalloc(size, GFP_KERNEL);
-
-	pr_info("Max logical packages: %u\n", __max_logical_packages);
 
 	for_each_present_cpu(cpu) {
 		unsigned int apicid = apic->cpu_present_to_apicid(cpu);

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#1459645

FromPeter Zijlstra <peterz@infradead.org>
Date2016-08-10 21:20 +0200
Message-ID<s4GJH-j6-19@gated-at.bofh.it>
In reply to#1459588
On Wed, Aug 10, 2016 at 04:15:38PM +0200, Jiri Olsa wrote:
> it's very likely I'm missing something, but seems to me
> that attached patch (untested) might work as well

Hmm, I think you're right. Earlier code (which hasn't survived) tried to
match logical and physical if possible, but that was busted and got
removed.

The code as is should indeed allow for this.

Maybe one nit, the variable is no longer used for a max, so maybe rename
it too?

> ---
> diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
> index 157bf0957219..003208bc8e44 100644
> --- a/arch/x86/kernel/smpboot.c
> +++ b/arch/x86/kernel/smpboot.c

> @@ -277,14 +276,8 @@ int topology_update_package_map(unsigned int apicid, unsigned int cpu)
>  	if (test_and_set_bit(pkg, physical_package_map))
>  		goto found;
>  
> +	new = __max_logical_packages++;
> +
>  	pr_info("APIC(%x) Converting physical %u to logical package %u\n",
>  		apicid, pkg, new);
>  	physical_to_logical_pkg[pkg] = new;
> @@ -340,7 +333,7 @@ static void __init smp_init_package_map(void)
>  		ncpus = 1;
>  	}
>  
> +	__max_logical_packages = 0;
>  
>  	/*
>  	 * Possibly larger than what we need as the number of apic ids per

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#1459618

FromPeter Zijlstra <peterz@infradead.org>
Date2016-08-10 21:20 +0200
Message-ID<s4GJH-j6-13@gated-at.bofh.it>
In reply to#1455885
On Wed, Aug 03, 2016 at 06:23:58PM +0200, Jiri Olsa wrote:
> Frank reported kernel panic when he disabled several cores in BIOS
> via following option:
> 
>   Core Disable Bitmap(Hex)   [0]
> 
> with number 0xFFE, which leaves 16 CPUs in system (out of 48).

That seems like a daft BIOS option. How wide spread is that? I can't
remember ever seeing that.

> The reason for the panic is wrong value of __max_logical_packages,
> which lets logical_package_map uninitialized and the uncore code
> relying on this map being properly initialized (maybe we should
> add some safety checks there as well).
> 
> The __max_logical_packages is computed as:
> 
>   DIV_ROUND_UP(total_cpus, ncpus);
>   - ncpus being number of cores
> 
> With above BIOS setup we get total_cpus == 16 which set
> __max_logical_packages to 2 (ncpus is 12). 
> 
> Once topology_update_package_map processes CPU with logical
> pkg over 2 we display above messages and fail to initialize
> the physical_to_logical_pkg map, which makes the uncore code
> crash.
> 
> The fix is to set __max_logical_packages directly to total_cpus,
> which should be the maximum possible logical ID of the pkg in
> any case.
> 
> Reported-by: Frank Ramsay <framsay@redhat.com>
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> ---
> diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
> index 157bf0957219..484f7d357c77 100644
> --- a/arch/x86/kernel/smpboot.c
> +++ b/arch/x86/kernel/smpboot.c
> @@ -340,7 +340,7 @@ static void __init smp_init_package_map(void)
>  		ncpus = 1;
>  	}
>  
> -	__max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus);
> +	__max_logical_packages = total_cpus;

This seems undesirable.. it would grow the bitmap unnecessarily big on
most setups.

Is there no way to detect the brain damage inflicted by that BIOS option
and fudge ncpus in that case?

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#1459861

FromJiri Olsa <jolsa@redhat.com>
Date2016-08-10 22:40 +0200
Message-ID<s4Isa-1A3-17@gated-at.bofh.it>
In reply to#1455885
ping

thanks,
jirka

On Wed, Aug 03, 2016 at 06:23:58PM +0200, Jiri Olsa wrote:
> Frank reported kernel panic when he disabled several cores in BIOS
> via following option:
> 
>   Core Disable Bitmap(Hex)   [0]
> 
> with number 0xFFE, which leaves 16 CPUs in system (out of 48).
> 
> The kernel panic below goes along with following messages:
> 
>  smpboot: Max logical packages: 2^M
>  smpboot: APIC(0) Converting physical 0 to logical package 0^M
>  smpboot: APIC(20) Converting physical 1 to logical package 1^M
>  smpboot: APIC(40) Package 2 exceeds logical package map^M
>  smpboot: CPU 8 APICId 40 disabled^M
>  smpboot: APIC(60) Package 3 exceeds logical package map^M
>  smpboot: CPU 12 APICId 60 disabled^M
>  ...
>  general protection fault: 0000 [#1] SMP^M
>  Modules linked in:^M
>  CPU: 15 PID: 1 Comm: swapper/0 Not tainted 4.7.0-rc5+ #1^M
>  Hardware name: SGI UV300/UV300, BIOS SGI UV 300 series BIOS 05/25/2016^M
>  task: ffff8801673e0000 ti: ffff8801673ac000 task.ti: ffff8801673ac000^M
>  RIP: 0010:[<ffffffff81014d54>]  [<ffffffff81014d54>] uncore_change_context+0xd4/0x180^M
>  ...
>   [<ffffffff810158ac>] uncore_event_init_cpu+0x6c/0x70^M
>   [<ffffffff81d8c91c>] intel_uncore_init+0x1c2/0x2dd^M
>   [<ffffffff81d8c75a>] ? uncore_cpu_setup+0x17/0x17^M
>   [<ffffffff81002190>] do_one_initcall+0x50/0x190^M
>   [<ffffffff810ab193>] ? parse_args+0x293/0x480^M
>   [<ffffffff81d87365>] kernel_init_freeable+0x1a5/0x249^M
>   [<ffffffff81d86a35>] ? set_debug_rodata+0x12/0x12^M
>   [<ffffffff816dc19e>] kernel_init+0xe/0x110^M
>   [<ffffffff816e93bf>] ret_from_fork+0x1f/0x40^M
>   [<ffffffff816dc190>] ? rest_init+0x80/0x80^M
> 
> The reason for the panic is wrong value of __max_logical_packages,
> which lets logical_package_map uninitialized and the uncore code
> relying on this map being properly initialized (maybe we should
> add some safety checks there as well).
> 
> The __max_logical_packages is computed as:
> 
>   DIV_ROUND_UP(total_cpus, ncpus);
>   - ncpus being number of cores
> 
> With above BIOS setup we get total_cpus == 16 which set
> __max_logical_packages to 2 (ncpus is 12). 
> 
> Once topology_update_package_map processes CPU with logical
> pkg over 2 we display above messages and fail to initialize
> the physical_to_logical_pkg map, which makes the uncore code
> crash.
> 
> The fix is to set __max_logical_packages directly to total_cpus,
> which should be the maximum possible logical ID of the pkg in
> any case.
> 
> Reported-by: Frank Ramsay <framsay@redhat.com>
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> ---
> diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
> index 157bf0957219..484f7d357c77 100644
> --- a/arch/x86/kernel/smpboot.c
> +++ b/arch/x86/kernel/smpboot.c
> @@ -340,7 +340,7 @@ static void __init smp_init_package_map(void)
>  		ncpus = 1;
>  	}
>  
> -	__max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus);
> +	__max_logical_packages = total_cpus;
>  
>  	/*
>  	 * Possibly larger than what we need as the number of apic ids per

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