* Re: [PATCH 4/6] powerpc/mm/64s/hash: Factor out change_memory_range()
From: Michael Ellerman @ 2021-03-16 6:30 UTC (permalink / raw)
To: Daniel Axtens, linuxppc-dev; +Cc: aneesh.kumar
In-Reply-To: <87k0r4q060.fsf@dja-thinkpad.axtens.net>
Daniel Axtens <dja@axtens.net> writes:
> Michael Ellerman <mpe@ellerman.id.au> writes:
>
>> Pull the loop calling hpte_updateboltedpp() out of
>> hash__change_memory_range() into a helper function. We need it to be a
>> separate function for the next patch.
>>
>> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
>> ---
>> arch/powerpc/mm/book3s64/hash_pgtable.c | 23 +++++++++++++++--------
>> 1 file changed, 15 insertions(+), 8 deletions(-)
>>
>> diff --git a/arch/powerpc/mm/book3s64/hash_pgtable.c b/arch/powerpc/mm/book3s64/hash_pgtable.c
>> index 03819c259f0a..3663d3cdffac 100644
>> --- a/arch/powerpc/mm/book3s64/hash_pgtable.c
>> +++ b/arch/powerpc/mm/book3s64/hash_pgtable.c
>> @@ -400,10 +400,23 @@ EXPORT_SYMBOL_GPL(hash__has_transparent_hugepage);
>> #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
>>
>> #ifdef CONFIG_STRICT_KERNEL_RWX
>> +static void change_memory_range(unsigned long start, unsigned long end,
>> + unsigned int step, unsigned long newpp)
>
> Looking at the call paths, this gets called only in bare metal, not
> virtualised: should the name reflect that?
It's also called on bare metal:
static bool hash__change_memory_range(unsigned long start, unsigned long end,
unsigned long newpp)
{
...
if (firmware_has_feature(FW_FEATURE_LPAR)) {
...
stop_machine_cpuslocked(change_memory_range_fn, &chmem_parms,
cpu_online_mask);
...
} else
change_memory_range(start, end, step, newpp);
^^^^^^^^^^^^^^^^^^^
>> +{
>> + unsigned long idx;
>> +
>> + pr_debug("Changing page protection on range 0x%lx-0x%lx, to 0x%lx, step 0x%x\n",
>> + start, end, newpp, step);
>> +
>> + for (idx = start; idx < end; idx += step)
>> + /* Not sure if we can do much with the return value */
>
> Hmm, I realise this comment isn't changed, but it did make me wonder
> what the return value!
>
> It turns out that the function doesn't actually return anything.
>
> Tracking back the history of hpte_updateboltedpp, it looks like it has
> not had a return value since the start of git history:
>
> ^1da177e4c3f4 include/asm-ppc64/machdep.h void (*hpte_updateboltedpp)(unsigned long newpp,
> 3c726f8dee6f5 include/asm-powerpc/machdep.h unsigned long ea,
> 1189be6508d45 include/asm-powerpc/machdep.h int psize, int ssize);
>
> The comment comes from commit cd65d6971334 ("powerpc/mm/hash: Implement
> mark_rodata_ro() for hash") where Balbir added the comment, but again I
> can't figure out what sort of return value there would be to ignore.
I suspect he just assumed there was a return value, and the comment is
saying we aren't really allowed to fail here, so what could we do?
In general these routines changing the kernel map permissions aren't
allowed to fail, because the callers don't cope with a failure, and at
least in some cases eg. RW -> RX the permission change is not optional.
> Should we drop the comment? (or return something from hpte_updateboltedpp)
I'll leave the comment for now, but we could probably drop it.
It would be good if hpte_updateboltedpp() could fail and return an
error. Currently pSeries_lpar_hpte_updateboltedpp() BUGs if the hcall
fails, because the only error cases are due to bad input on our part.
And similarly native_hpte_updateboltedpp() panics if we give it bad
input.
We may still need to panic() at a higher level, ie. adding execute to a
mapping is not optional. But possibly for some changes, like RW->RO we
could WARN and continue.
And I guess for modules we could eventually plumb the error all the way
out and fail the module load.
>> + mmu_hash_ops.hpte_updateboltedpp(newpp, idx, mmu_linear_psize,
>> + mmu_kernel_ssize);
>> +}
>> +
>> static bool hash__change_memory_range(unsigned long start, unsigned long end,
>> unsigned long newpp)
>> {
>> - unsigned long idx;
>> unsigned int step, shift;
>>
>> shift = mmu_psize_defs[mmu_linear_psize].shift;
>> @@ -415,13 +428,7 @@ static bool hash__change_memory_range(unsigned long start, unsigned long end,
>> if (start >= end)
>> return false;
>>
>> - pr_debug("Changing page protection on range 0x%lx-0x%lx, to 0x%lx, step 0x%x\n",
>> - start, end, newpp, step);
>> -
>> - for (idx = start; idx < end; idx += step)
>> - /* Not sure if we can do much with the return value */
>> - mmu_hash_ops.hpte_updateboltedpp(newpp, idx, mmu_linear_psize,
>> - mmu_kernel_ssize);
>> + change_memory_range(start, end, step, newpp);
>
> Looking at how change_memory_range is called, step is derived by:
>
> shift = mmu_psize_defs[mmu_linear_psize].shift;
> step = 1 << shift;
>
> We probably therefore don't really need to pass step in to
> change_memory_range. Having said that, I'm not sure it would really be that
> much tidier to compute step in change_memory_range, especially since we
> also need step for the other branch in hash__change_memory_range.
Hmm yeah, swings and roundabouts. I think I'll leave it as is, so that
we're only calculating step in one place.
> Beyond that it all looks reasonable to me!
>
> I also checked that the loop operations made sense, I think they do - we
> cover from start inclusive to end exclusive and the alignment is done
> before we call into change_memory_range.
Thanks.
cheers
^ permalink raw reply
* Re: [PATCH v3 00/41] KVM: PPC: Book3S: C-ify the P9 entry/exit code
From: Nicholas Piggin @ 2021-03-16 6:06 UTC (permalink / raw)
To: kvm-ppc; +Cc: Fabiano Rosas, linuxppc-dev, Daniel Axtens
In-Reply-To: <20210305150638.2675513-1-npiggin@gmail.com>
Excerpts from Nicholas Piggin's message of March 6, 2021 1:05 am:
> This tidies up things, and fixes a few corner cases and unfinished
> "XXX:" bits. The major one being "bad host interrupt" detection and
> handling (taking a MCE/SRESET while switching into guest regs) which
> was missing previously from the new P9 path.
>
> Adds a few new patches and makes some changes for issues noticed
> by reviewers (thank you).
I've put a tree up here with latest changes.
https://github.com/npiggin/linux/tree/kvm-in-c
Should include all the review comments from this thread so far, no
other major changes.
I'll hold off posting out another series probably at least until
powerpc next solidifies a bit more (some of the interrupt handler
changes pending there might clash).
Thanks,
Nick
^ permalink raw reply
* Re: [PATCH] powerpc/numa: Fix topology_physical_package_id() on pSeries
From: Srikar Dronamraju @ 2021-03-16 5:23 UTC (permalink / raw)
To: G
Cc: Nathan Lynch, Daniel Henrique Barboza, Greg Kurz, Vasant Hegde,
linuxppc-dev, David Gibson
In-Reply-To: <20210312143154.3181109-1-clg@kaod.org>
* C?dric Le Goater <clg@kaod.org> [2021-03-12 15:31:54]:
> Initial commit 15863ff3b8da ("powerpc: Make chip-id information
> available to userspace") introduce a cpu_to_chip_id() routine for the
> PowerNV platform using the "ibm,chip-id" property to query the chip id
> of a CPU. But PAPR does not specify such a property and the node id
> query is broken.
>
> Use cpu_to_node() instead which guarantees to have a correct value on
> all platforms, PowerNV an pSeries.
>
While this looks good to me, @mpe had reservations on using nid as chip-id.
https://lore.kernel.org/linuxppc-dev/87lfwhypv0.fsf@concordia.ellerman.id.au/t/#u
He may be okay with using nid as a "virtual" package id in a pseries
environment.
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
> Cc: Nathan Lynch <nathanl@linux.ibm.com>
> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
> Cc: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
> Signed-off-by: Cédric Le Goater <clg@kaod.org>
> ---
> arch/powerpc/include/asm/topology.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/include/asm/topology.h b/arch/powerpc/include/asm/topology.h
> index 3beeb030cd78..887c42a4e43d 100644
> --- a/arch/powerpc/include/asm/topology.h
> +++ b/arch/powerpc/include/asm/topology.h
> @@ -123,7 +123,7 @@ static inline int cpu_to_coregroup_id(int cpu)
> #ifdef CONFIG_PPC64
> #include <asm/smp.h>
>
> -#define topology_physical_package_id(cpu) (cpu_to_chip_id(cpu))
> +#define topology_physical_package_id(cpu) (cpu_to_node(cpu))
>
> #define topology_sibling_cpumask(cpu) (per_cpu(cpu_sibling_map, cpu))
> #define topology_core_cpumask(cpu) (cpu_cpu_mask(cpu))
> --
> 2.26.2
>
--
Thanks and Regards
Srikar Dronamraju
^ permalink raw reply
* Re: [PATCH] scsi: ibmvfc: Switch to using the new API kobj_to_dev()
From: Martin K. Petersen @ 2021-03-16 3:14 UTC (permalink / raw)
To: Jiapeng Chong, tyreld
Cc: Martin K . Petersen, linux-scsi, jejb, linux-kernel, paulus,
linuxppc-dev
In-Reply-To: <1614850124-54111-1-git-send-email-jiapeng.chong@linux.alibaba.com>
On Thu, 4 Mar 2021 17:28:44 +0800, Jiapeng Chong wrote:
> Fix the following coccicheck warnings:
>
> ./drivers/scsi/ibmvscsi/ibmvfc.c:3483:60-61: WARNING opportunity for
> kobj_to_dev().
Applied to 5.13/scsi-queue, thanks!
[1/1] scsi: ibmvfc: Switch to using the new API kobj_to_dev()
https://git.kernel.org/mkp/scsi/c/18c2a59a4190
--
Martin K. Petersen Oracle Linux Engineering
^ permalink raw reply
* Re: [PATCH 3/3] powerpc/qspinlock: Use generic smp_cond_load_relaxed
From: Nicholas Piggin @ 2021-03-16 4:59 UTC (permalink / raw)
To: Davidlohr Bueso
Cc: will, Davidlohr Bueso, peterz, linux-kernel, mingo, paulus,
longman, linuxppc-dev
In-Reply-To: <20210309015950.27688-4-dave@stgolabs.net>
Excerpts from Davidlohr Bueso's message of March 9, 2021 11:59 am:
> 49a7d46a06c3 (powerpc: Implement smp_cond_load_relaxed()) added
> busy-waiting pausing with a preferred SMT priority pattern, lowering
> the priority (reducing decode cycles) during the whole loop slowpath.
>
> However, data shows that while this pattern works well with simple
> spinlocks, queued spinlocks benefit more being kept in medium priority,
> with a cpu_relax() instead, being a low+medium combo on powerpc.
Thanks for tracking this down and the comprehensive results, great
work.
It's only a relatively recent patch, so I think the revert is a
good idea (i.e., don't keep it around for possibly other code to
hit problems with).
One request, could you add a comment in place that references
smp_cond_load_relaxed() so this commit can be found again if
someone looks at it? Something like this
/*
* smp_cond_load_relaxed was found to have performance problems if
* implemented with spin_begin()/spin_end().
*/
I wonder if it should have a Fixes: tag to the original commit as
well.
Otherwise,
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Thanks,
Nick
>
> Data is from three benchmarks on a Power9: 9008-22L 64 CPUs with
> 2 sockets and 8 threads per core.
>
> 1. locktorture.
>
> This is data for the lowest and most artificial/pathological level,
> with increasing thread counts pounding on the lock. Metrics are total
> ops/minute. Despite some small hits in the 4-8 range, scenarios are
> either neutral or favorable to this patch.
>
> +=========+==========+==========+=======+
> | # tasks | vanilla | dirty | %diff |
> +=========+==========+==========+=======+
> | 2 | 46718565 | 48751350 | 4.35 |
> +---------+----------+----------+-------+
> | 4 | 51740198 | 50369082 | -2.65 |
> +---------+----------+----------+-------+
> | 8 | 63756510 | 62568821 | -1.86 |
> +---------+----------+----------+-------+
> | 16 | 67824531 | 70966546 | 4.63 |
> +---------+----------+----------+-------+
> | 32 | 53843519 | 61155508 | 13.58 |
> +---------+----------+----------+-------+
> | 64 | 53005778 | 53104412 | 0.18 |
> +---------+----------+----------+-------+
> | 128 | 53331980 | 54606910 | 2.39 |
> +=========+==========+==========+=======+
>
> 2. sockperf (tcp throughput)
>
> Here a client will do one-way throughput tests to a localhost server, with
> increasing message sizes, dealing with the sk_lock. This patch shows to put
> the performance of the qspinlock back to par with that of the simple lock:
>
> simple-spinlock vanilla dirty
> Hmean 14 73.50 ( 0.00%) 54.44 * -25.93%* 73.45 * -0.07%*
> Hmean 100 654.47 ( 0.00%) 385.61 * -41.08%* 771.43 * 17.87%*
> Hmean 300 2719.39 ( 0.00%) 2181.67 * -19.77%* 2666.50 * -1.94%*
> Hmean 500 4400.59 ( 0.00%) 3390.77 * -22.95%* 4322.14 * -1.78%*
> Hmean 850 6726.21 ( 0.00%) 5264.03 * -21.74%* 6863.12 * 2.04%*
>
> 3. dbench (tmpfs)
>
> Configured to run with up to ncpusx8 clients, it shows both latency and
> throughput metrics. For the latency, with the exception of the 64 case,
> there is really nothing to go by:
> vanilla dirty
> Amean latency-1 1.67 ( 0.00%) 1.67 * 0.09%*
> Amean latency-2 2.15 ( 0.00%) 2.08 * 3.36%*
> Amean latency-4 2.50 ( 0.00%) 2.56 * -2.27%*
> Amean latency-8 2.49 ( 0.00%) 2.48 * 0.31%*
> Amean latency-16 2.69 ( 0.00%) 2.72 * -1.37%*
> Amean latency-32 2.96 ( 0.00%) 3.04 * -2.60%*
> Amean latency-64 7.78 ( 0.00%) 8.17 * -5.07%*
> Amean latency-512 186.91 ( 0.00%) 186.41 * 0.27%*
>
> For the dbench4 Throughput (misleading but traditional) there's a small
> but rather constant improvement:
>
> vanilla dirty
> Hmean 1 849.13 ( 0.00%) 851.51 * 0.28%*
> Hmean 2 1664.03 ( 0.00%) 1663.94 * -0.01%*
> Hmean 4 3073.70 ( 0.00%) 3104.29 * 1.00%*
> Hmean 8 5624.02 ( 0.00%) 5694.16 * 1.25%*
> Hmean 16 9169.49 ( 0.00%) 9324.43 * 1.69%*
> Hmean 32 11969.37 ( 0.00%) 12127.09 * 1.32%*
> Hmean 64 15021.12 ( 0.00%) 15243.14 * 1.48%*
> Hmean 512 14891.27 ( 0.00%) 15162.11 * 1.82%*
>
> Measuring the dbench4 Per-VFS Operation latency, shows some very minor
> differences within the noise level, around the 0-1% ranges.
>
> Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
> ---
> arch/powerpc/include/asm/barrier.h | 16 ----------------
> 1 file changed, 16 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/barrier.h b/arch/powerpc/include/asm/barrier.h
> index aecfde829d5d..7ae29cfb06c0 100644
> --- a/arch/powerpc/include/asm/barrier.h
> +++ b/arch/powerpc/include/asm/barrier.h
> @@ -80,22 +80,6 @@ do { \
> ___p1; \
> })
>
> -#ifdef CONFIG_PPC64
> -#define smp_cond_load_relaxed(ptr, cond_expr) ({ \
> - typeof(ptr) __PTR = (ptr); \
> - __unqual_scalar_typeof(*ptr) VAL; \
> - VAL = READ_ONCE(*__PTR); \
> - if (unlikely(!(cond_expr))) { \
> - spin_begin(); \
> - do { \
> - VAL = READ_ONCE(*__PTR); \
> - } while (!(cond_expr)); \
> - spin_end(); \
> - } \
> - (typeof(*ptr))VAL; \
> -})
> -#endif
> -
> #ifdef CONFIG_PPC_BOOK3S_64
> #define NOSPEC_BARRIER_SLOT nop
> #elif defined(CONFIG_PPC_FSL_BOOK3E)
> --
> 2.26.2
>
>
^ permalink raw reply
* [PATCH] powerpc: arch/powerpc/kernel/setup_64.c - cleanup warnings
From: He Ying @ 2021-03-16 4:11 UTC (permalink / raw)
To: mpe, benh, paulus, npiggin, dja, akpm, aneesh.kumar, rppt, ardb,
clg, christophe.leroy
Cc: johnny.chenyi, linuxppc-dev, linux-kernel
warning: symbol 'rfi_flush' was not declared.
warning: symbol 'entry_flush' was not declared.
warning: symbol 'uaccess_flush' was not declared.
We found warnings above in arch/powerpc/kernel/setup_64.c by using
sparse tool.
Define 'entry_flush' and 'uaccess_flush' as static because they are not
referenced outside the file. Include asm/security_features.h in which
'rfi_flush' is declared.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: He Ying <heying24@huawei.com>
---
arch/powerpc/kernel/setup_64.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 560ed8b975e7..f92d72a7e7ce 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -68,6 +68,7 @@
#include <asm/early_ioremap.h>
#include <asm/pgalloc.h>
#include <asm/asm-prototypes.h>
+#include <asm/security_features.h>
#include "setup.h"
@@ -949,8 +950,8 @@ static bool no_rfi_flush;
static bool no_entry_flush;
static bool no_uaccess_flush;
bool rfi_flush;
-bool entry_flush;
-bool uaccess_flush;
+static bool entry_flush;
+static bool uaccess_flush;
DEFINE_STATIC_KEY_FALSE(uaccess_flush_key);
EXPORT_SYMBOL(uaccess_flush_key);
--
2.17.1
^ permalink raw reply related
* Re: [PATCH v9 2/8] powerpc/lib/code-patching: Set up Strict RWX patching earlier
From: Russell Currey @ 2021-03-16 3:36 UTC (permalink / raw)
To: Jordan Niethe, linuxppc-dev
Cc: christophe.leroy, naveen.n.rao, ajd, npiggin, dja
In-Reply-To: <20210316031741.1004850-2-jniethe5@gmail.com>
On Tue, 2021-03-16 at 14:17 +1100, Jordan Niethe wrote:
> setup_text_poke_area() is a late init call so it runs before
> mark_rodata_ro() and after the init calls. This lets all the init
> code
> patching simply write to their locations. In the future, kprobes is
> going to allocate its instruction pages RO which means they will need
> setup_text__poke_area() to have been already called for their code
> patching. However, init_kprobes() (which allocates and patches some
> instruction pages) is an early init call so it happens before
> setup_text__poke_area().
>
> start_kernel() calls poking_init() before any of the init calls. On
> powerpc, poking_init() is currently a nop. setup_text_poke_area()
> relies
> on kernel virtual memory, cpu hotplug and per_cpu_areas being setup.
> setup_per_cpu_areas(), boot_cpu_hotplug_init() and mm_init() are
> called
> before poking_init().
>
> Turn setup_text_poke_area() into poking_init().
>
> Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Good job finding & fixing this bug!
Reviewed-by: Russell Currey <ruscur@russell.cc>
> ---
> v9: New to series
> ---
> arch/powerpc/lib/code-patching.c | 12 ++++--------
> 1 file changed, 4 insertions(+), 8 deletions(-)
>
> diff --git a/arch/powerpc/lib/code-patching.c
> b/arch/powerpc/lib/code-patching.c
> index 2333625b5e31..b28afa1133db 100644
> --- a/arch/powerpc/lib/code-patching.c
> +++ b/arch/powerpc/lib/code-patching.c
> @@ -65,14 +65,11 @@ static int text_area_cpu_down(unsigned int cpu)
> }
>
> /*
> - * Run as a late init call. This allows all the boot time patching
> to be done
> - * simply by patching the code, and then we're called here prior to
> - * mark_rodata_ro(), which happens after all init calls are run.
> Although
> - * BUG_ON() is rude, in this case it should only happen if ENOMEM,
> and we judge
> - * it as being preferable to a kernel that will crash later when
> someone tries
> - * to use patch_instruction().
> + * Although BUG_ON() is rude, in this case it should only happen if
> ENOMEM, and
> + * we judge it as being preferable to a kernel that will crash later
> when
> + * someone tries to use patch_instruction().
> */
> -static int __init setup_text_poke_area(void)
> +int __init poking_init(void)
> {
> BUG_ON(!cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
> "powerpc/text_poke:online", text_area_cpu_up,
> @@ -80,7 +77,6 @@ static int __init setup_text_poke_area(void)
>
> return 0;
> }
> -late_initcall(setup_text_poke_area);
>
> /*
> * This can be called for kernel text or a module.
^ permalink raw reply
* Re: [PATCH v3 12/41] KVM: PPC: Book3S 64: Move hcall early register setup to KVM
From: Nicholas Piggin @ 2021-03-16 3:43 UTC (permalink / raw)
To: Daniel Axtens, kvm-ppc; +Cc: linuxppc-dev
In-Reply-To: <87czw57wn8.fsf@linkitivity.dja.id.au>
Excerpts from Daniel Axtens's message of March 12, 2021 3:45 pm:
> Nicholas Piggin <npiggin@gmail.com> writes:
>
>> System calls / hcalls have a different calling convention than
>> other interrupts, so there is code in the KVMTEST to massage these
>> into the same form as other interrupt handlers.
>>
>> Move this work into the KVM hcall handler. This means teaching KVM
>> a little more about the low level interrupt handler setup, PACA save
>> areas, etc., although that's not obviously worse than the current
>> approach of coming up with an entirely different interrupt register
>> / save convention.
>>
>> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
>> ---
>> arch/powerpc/include/asm/exception-64s.h | 13 ++++++++
>> arch/powerpc/kernel/exceptions-64s.S | 42 +-----------------------
>> arch/powerpc/kvm/book3s_64_entry.S | 17 ++++++++++
>> 3 files changed, 31 insertions(+), 41 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h
>> index c1a8aac01cf9..bb6f78fcf981 100644
>> --- a/arch/powerpc/include/asm/exception-64s.h
>> +++ b/arch/powerpc/include/asm/exception-64s.h
>> @@ -35,6 +35,19 @@
>> /* PACA save area size in u64 units (exgen, exmc, etc) */
>> #define EX_SIZE 10
>>
>> +/* PACA save area offsets */
>> +#define EX_R9 0
>> +#define EX_R10 8
>> +#define EX_R11 16
>> +#define EX_R12 24
>> +#define EX_R13 32
>> +#define EX_DAR 40
>> +#define EX_DSISR 48
>> +#define EX_CCR 52
>> +#define EX_CFAR 56
>> +#define EX_PPR 64
>> +#define EX_CTR 72
>> +
>> /*
>> * maximum recursive depth of MCE exceptions
>> */
>> diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
>> index 292435bd80f0..b7092ba87da8 100644
>> --- a/arch/powerpc/kernel/exceptions-64s.S
>> +++ b/arch/powerpc/kernel/exceptions-64s.S
>> @@ -21,22 +21,6 @@
>> #include <asm/feature-fixups.h>
>> #include <asm/kup.h>
>>
>> -/* PACA save area offsets (exgen, exmc, etc) */
>> -#define EX_R9 0
>> -#define EX_R10 8
>> -#define EX_R11 16
>> -#define EX_R12 24
>> -#define EX_R13 32
>> -#define EX_DAR 40
>> -#define EX_DSISR 48
>> -#define EX_CCR 52
>> -#define EX_CFAR 56
>> -#define EX_PPR 64
>> -#define EX_CTR 72
>> -.if EX_SIZE != 10
>> - .error "EX_SIZE is wrong"
>> -.endif
>> -
>> /*
>> * Following are fixed section helper macros.
>> *
>> @@ -1964,29 +1948,8 @@ EXC_VIRT_END(system_call, 0x4c00, 0x100)
>>
>> #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
>> TRAMP_REAL_BEGIN(system_call_kvm)
>> - /*
>> - * This is a hcall, so register convention is as above, with these
>> - * differences:
>> - * r13 = PACA
>> - * ctr = orig r13
>> - * orig r10 saved in PACA
>> - */
>> - /*
>> - * Save the PPR (on systems that support it) before changing to
>> - * HMT_MEDIUM. That allows the KVM code to save that value into the
>> - * guest state (it is the guest's PPR value).
>> - */
>> -BEGIN_FTR_SECTION
>> - mfspr r10,SPRN_PPR
>> - std r10,HSTATE_PPR(r13)
>> -END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
>> - HMT_MEDIUM
>> mfctr r10
>> - SET_SCRATCH0(r10)
>> - mfcr r10
>> - std r12,HSTATE_SCRATCH0(r13)
>> - sldi r12,r10,32
>> - ori r12,r12,0xc00
>> + SET_SCRATCH0(r10) /* Save r13 in SCRATCH0 */
>
> If I've understood correctly, you've saved the _original_/guest r13 in
> SCRATCH0. That makes sense - it just took me a while to follow the
> logic, especially because the parameter to SET_SCRATCH0 is r10, not r13.
>
> I would probably expand the comment to say the original or guest r13 (as
> you do in the comment at the start of kvmppc_hcall), but if there's a
> convention here that I've missed that might not be necessary.
There is a convention which is that all kvm interrupts including system
call come in with r13 saved in SCRATCH0, although that's all in a state
of flux throughput this series of course.
I added the comment because I moved the bigger comment here, I think
that's okay because you're always referring to interrupted context
(i.e., guest in this case) when talking about saved registers.
>
>> #ifdef CONFIG_RELOCATABLE
>> /*
>> * Requires __LOAD_FAR_HANDLER beause kvmppc_hcall lives
>> @@ -1994,15 +1957,12 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
>> */
>> __LOAD_FAR_HANDLER(r10, kvmppc_hcall)
>> mtctr r10
>> - ld r10,PACA_EXGEN+EX_R10(r13)
>> bctr
>> #else
>> - ld r10,PACA_EXGEN+EX_R10(r13)
>> b kvmppc_hcall
>> #endif
>> #endif
>>
>> -
>> /**
>> * Interrupt 0xd00 - Trace Interrupt.
>> * This is a synchronous interrupt in response to instruction step or
>> diff --git a/arch/powerpc/kvm/book3s_64_entry.S b/arch/powerpc/kvm/book3s_64_entry.S
>> index 8cf5e24a81eb..a7b6edd18bc8 100644
>> --- a/arch/powerpc/kvm/book3s_64_entry.S
>> +++ b/arch/powerpc/kvm/book3s_64_entry.S
>> @@ -14,6 +14,23 @@
>> .global kvmppc_hcall
>> .balign IFETCH_ALIGN_BYTES
>> kvmppc_hcall:
>> + /*
>> + * This is a hcall, so register convention is as
>> + * Documentation/powerpc/papr_hcalls.rst, with these additions:
>> + * R13 = PACA
>> + * guest R13 saved in SPRN_SCRATCH0
>> + * R10 = free
>> + */
>> +BEGIN_FTR_SECTION
>> + mfspr r10,SPRN_PPR
>> + std r10,HSTATE_PPR(r13)
>> +END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
>
> Do we want to preserve the comment about why we save the PPR?
Wouldn't hurt. I think the reason the comment is there is because it's a
difference with system calls. Hcalls preserve the PPR, system calls do not.
Should probably leave the "orig r10 saved in the PACA" comment too.
>
>> + HMT_MEDIUM
>> + mfcr r10
>> + std r12,HSTATE_SCRATCH0(r13)
>> + sldi r12,r10,32
>> + ori r12,r12,0xc00
>
> I see that this is a direct copy from the earlier code, but it confuses
> me a bit. Looking at exceptions-64s.S, there's the following comment:
>
> * In HPT, sc 1 always goes to 0xc00 real mode. In RADIX, sc 1 can go to
> * 0x4c00 virtual mode.
>
> However, this code uncondionally sets the low bits to be c00, even if
> the exception came in via 4c00. Is this right? Do we need to pass
> that through somehow?
We don't need to. The "trap" numbers are always the real-mode vectors
(except scv which is a bit weird) by convention.
>
>> + ld r10,PACA_EXGEN+EX_R10(r13)
>>
>
> Otherwise, this looks good to me so far.
Thanks,
Nick
^ permalink raw reply
* [PATCH v9 8/8] powerpc/32: use set_memory_attr()
From: Jordan Niethe @ 2021-03-16 3:17 UTC (permalink / raw)
To: linuxppc-dev
Cc: christophe.leroy, ajd, npiggin, naveen.n.rao, Jordan Niethe, dja
In-Reply-To: <20210316031741.1004850-1-jniethe5@gmail.com>
From: Christophe Leroy <christophe.leroy@c-s.fr>
Use set_memory_attr() instead of the PPC32 specific change_page_attr()
change_page_attr() was checking that the address was not mapped by
blocks and was handling highmem, but that's unneeded because the
affected pages can't be in highmem and block mapping verification
is already done by the callers.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[ruscur: rebase on powerpc/merge with Christophe's new patches]
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
---
arch/powerpc/mm/pgtable_32.c | 60 ++++++------------------------------
1 file changed, 10 insertions(+), 50 deletions(-)
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index e0ec67a16887..dcf5ecca19d9 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -23,6 +23,7 @@
#include <linux/highmem.h>
#include <linux/memblock.h>
#include <linux/slab.h>
+#include <linux/set_memory.h>
#include <asm/pgalloc.h>
#include <asm/fixmap.h>
@@ -132,64 +133,20 @@ void __init mapin_ram(void)
}
}
-static int __change_page_attr_noflush(struct page *page, pgprot_t prot)
-{
- pte_t *kpte;
- unsigned long address;
-
- BUG_ON(PageHighMem(page));
- address = (unsigned long)page_address(page);
-
- if (v_block_mapped(address))
- return 0;
- kpte = virt_to_kpte(address);
- if (!kpte)
- return -EINVAL;
- __set_pte_at(&init_mm, address, kpte, mk_pte(page, prot), 0);
-
- return 0;
-}
-
-/*
- * Change the page attributes of an page in the linear mapping.
- *
- * THIS DOES NOTHING WITH BAT MAPPINGS, DEBUG USE ONLY
- */
-static int change_page_attr(struct page *page, int numpages, pgprot_t prot)
-{
- int i, err = 0;
- unsigned long flags;
- struct page *start = page;
-
- local_irq_save(flags);
- for (i = 0; i < numpages; i++, page++) {
- err = __change_page_attr_noflush(page, prot);
- if (err)
- break;
- }
- wmb();
- local_irq_restore(flags);
- flush_tlb_kernel_range((unsigned long)page_address(start),
- (unsigned long)page_address(page));
- return err;
-}
-
void mark_initmem_nx(void)
{
- struct page *page = virt_to_page(_sinittext);
unsigned long numpages = PFN_UP((unsigned long)_einittext) -
PFN_DOWN((unsigned long)_sinittext);
if (v_block_mapped((unsigned long)_sinittext))
mmu_mark_initmem_nx();
else
- change_page_attr(page, numpages, PAGE_KERNEL);
+ set_memory_attr((unsigned long)_sinittext, numpages, PAGE_KERNEL);
}
#ifdef CONFIG_STRICT_KERNEL_RWX
void mark_rodata_ro(void)
{
- struct page *page;
unsigned long numpages;
if (v_block_mapped((unsigned long)_stext + 1)) {
@@ -198,20 +155,18 @@ void mark_rodata_ro(void)
return;
}
- page = virt_to_page(_stext);
numpages = PFN_UP((unsigned long)_etext) -
PFN_DOWN((unsigned long)_stext);
- change_page_attr(page, numpages, PAGE_KERNEL_ROX);
+ set_memory_attr((unsigned long)_stext, numpages, PAGE_KERNEL_ROX);
/*
* mark .rodata as read only. Use __init_begin rather than __end_rodata
* to cover NOTES and EXCEPTION_TABLE.
*/
- page = virt_to_page(__start_rodata);
numpages = PFN_UP((unsigned long)__init_begin) -
PFN_DOWN((unsigned long)__start_rodata);
- change_page_attr(page, numpages, PAGE_KERNEL_RO);
+ set_memory_attr((unsigned long)__start_rodata, numpages, PAGE_KERNEL_RO);
// mark_initmem_nx() should have already run by now
ptdump_check_wx();
@@ -221,9 +176,14 @@ void mark_rodata_ro(void)
#ifdef CONFIG_DEBUG_PAGEALLOC
void __kernel_map_pages(struct page *page, int numpages, int enable)
{
+ unsigned long addr = (unsigned long)page_address(page);
+
if (PageHighMem(page))
return;
- change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
+ if (enable)
+ set_memory_attr(addr, numpages, PAGE_KERNEL);
+ else
+ set_memory_attr(addr, numpages, __pgprot(0));
}
#endif /* CONFIG_DEBUG_PAGEALLOC */
--
2.25.1
^ permalink raw reply related
* [PATCH v9 7/8] powerpc/mm: implement set_memory_attr()
From: Jordan Niethe @ 2021-03-16 3:17 UTC (permalink / raw)
To: linuxppc-dev
Cc: christophe.leroy, ajd, npiggin, kbuild test robot, naveen.n.rao,
Jordan Niethe, dja
In-Reply-To: <20210316031741.1004850-1-jniethe5@gmail.com>
From: Christophe Leroy <christophe.leroy@c-s.fr>
In addition to the set_memory_xx() functions which allows to change
the memory attributes of not (yet) used memory regions, implement a
set_memory_attr() function to:
- set the final memory protection after init on currently used
kernel regions.
- enable/disable kernel memory regions in the scope of DEBUG_PAGEALLOC.
Unlike the set_memory_xx() which can act in three step as the regions
are unused, this function must modify 'on the fly' as the kernel is
executing from them. At the moment only PPC32 will use it and changing
page attributes on the fly is not an issue.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reported-by: kbuild test robot <lkp@intel.com>
[ruscur: cast "data" to unsigned long instead of int]
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
---
arch/powerpc/include/asm/set_memory.h | 2 ++
arch/powerpc/mm/pageattr.c | 33 +++++++++++++++++++++++++++
2 files changed, 35 insertions(+)
diff --git a/arch/powerpc/include/asm/set_memory.h b/arch/powerpc/include/asm/set_memory.h
index 64011ea444b4..b040094f7920 100644
--- a/arch/powerpc/include/asm/set_memory.h
+++ b/arch/powerpc/include/asm/set_memory.h
@@ -29,4 +29,6 @@ static inline int set_memory_x(unsigned long addr, int numpages)
return change_memory_attr(addr, numpages, SET_MEMORY_X);
}
+int set_memory_attr(unsigned long addr, int numpages, pgprot_t prot);
+
#endif
diff --git a/arch/powerpc/mm/pageattr.c b/arch/powerpc/mm/pageattr.c
index 2da3fbab6ff7..2fde1b195c85 100644
--- a/arch/powerpc/mm/pageattr.c
+++ b/arch/powerpc/mm/pageattr.c
@@ -79,3 +79,36 @@ int change_memory_attr(unsigned long addr, int numpages, long action)
return apply_to_existing_page_range(&init_mm, start, sz,
change_page_attr, (void *)action);
}
+
+/*
+ * Set the attributes of a page:
+ *
+ * This function is used by PPC32 at the end of init to set final kernel memory
+ * protection. It includes changing the maping of the page it is executing from
+ * and data pages it is using.
+ */
+static int set_page_attr(pte_t *ptep, unsigned long addr, void *data)
+{
+ pgprot_t prot = __pgprot((unsigned long)data);
+
+ spin_lock(&init_mm.page_table_lock);
+
+ set_pte_at(&init_mm, addr, ptep, pte_modify(*ptep, prot));
+ flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
+
+ spin_unlock(&init_mm.page_table_lock);
+
+ return 0;
+}
+
+int set_memory_attr(unsigned long addr, int numpages, pgprot_t prot)
+{
+ unsigned long start = ALIGN_DOWN(addr, PAGE_SIZE);
+ unsigned long sz = numpages * PAGE_SIZE;
+
+ if (numpages <= 0)
+ return 0;
+
+ return apply_to_existing_page_range(&init_mm, start, sz, set_page_attr,
+ (void *)pgprot_val(prot));
+}
--
2.25.1
^ permalink raw reply related
* [PATCH v9 6/8] powerpc/configs: Enable STRICT_MODULE_RWX in skiroot_defconfig
From: Jordan Niethe @ 2021-03-16 3:17 UTC (permalink / raw)
To: linuxppc-dev
Cc: christophe.leroy, ajd, Joel Stanley, npiggin, naveen.n.rao,
Jordan Niethe, dja
In-Reply-To: <20210316031741.1004850-1-jniethe5@gmail.com>
From: Russell Currey <ruscur@russell.cc>
skiroot_defconfig is the only powerpc defconfig with STRICT_KERNEL_RWX
enabled, and if you want memory protection for kernel text you'd want it
for modules too, so enable STRICT_MODULE_RWX there.
Acked-by: Joel Stanley <joel@joel.id.au>
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
---
arch/powerpc/configs/skiroot_defconfig | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/powerpc/configs/skiroot_defconfig b/arch/powerpc/configs/skiroot_defconfig
index b806a5d3a695..50fe06cb3a31 100644
--- a/arch/powerpc/configs/skiroot_defconfig
+++ b/arch/powerpc/configs/skiroot_defconfig
@@ -50,6 +50,7 @@ CONFIG_CMDLINE="console=tty0 console=hvc0 ipr.fast_reboot=1 quiet"
# CONFIG_PPC_MEM_KEYS is not set
CONFIG_JUMP_LABEL=y
CONFIG_STRICT_KERNEL_RWX=y
+CONFIG_STRICT_MODULE_RWX=y
CONFIG_MODULES=y
CONFIG_MODULE_UNLOAD=y
CONFIG_MODULE_SIG_FORCE=y
--
2.25.1
^ permalink raw reply related
* [PATCH v9 5/8] powerpc: Set ARCH_HAS_STRICT_MODULE_RWX
From: Jordan Niethe @ 2021-03-16 3:17 UTC (permalink / raw)
To: linuxppc-dev
Cc: christophe.leroy, ajd, npiggin, naveen.n.rao, Jordan Niethe, dja
In-Reply-To: <20210316031741.1004850-1-jniethe5@gmail.com>
From: Russell Currey <ruscur@russell.cc>
To enable strict module RWX on powerpc, set:
CONFIG_STRICT_MODULE_RWX=y
You should also have CONFIG_STRICT_KERNEL_RWX=y set to have any real
security benefit.
ARCH_HAS_STRICT_MODULE_RWX is set to require ARCH_HAS_STRICT_KERNEL_RWX.
This is due to a quirk in arch/Kconfig and arch/powerpc/Kconfig that
makes STRICT_MODULE_RWX *on by default* in configurations where
STRICT_KERNEL_RWX is *unavailable*.
Since this doesn't make much sense, and module RWX without kernel RWX
doesn't make much sense, having the same dependencies as kernel RWX
works around this problem.
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
---
arch/powerpc/Kconfig | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 4498a27ac9db..d9cadc4212d0 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -137,6 +137,7 @@ config PPC
select ARCH_HAS_SCALED_CPUTIME if VIRT_CPU_ACCOUNTING_NATIVE && PPC_BOOK3S_64
select ARCH_HAS_SET_MEMORY
select ARCH_HAS_STRICT_KERNEL_RWX if ((PPC_BOOK3S_64 || PPC32) && !HIBERNATION)
+ select ARCH_HAS_STRICT_MODULE_RWX if ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_HAS_UACCESS_FLUSHCACHE
select ARCH_HAS_COPY_MC if PPC64
--
2.25.1
^ permalink raw reply related
* [PATCH v9 4/8] powerpc/mm/ptdump: debugfs handler for W+X checks at runtime
From: Jordan Niethe @ 2021-03-16 3:17 UTC (permalink / raw)
To: linuxppc-dev
Cc: christophe.leroy, ajd, Kees Cook, npiggin, naveen.n.rao,
Jordan Niethe, dja
In-Reply-To: <20210316031741.1004850-1-jniethe5@gmail.com>
From: Russell Currey <ruscur@russell.cc>
Very rudimentary, just
echo 1 > [debugfs]/check_wx_pages
and check the kernel log. Useful for testing strict module RWX.
Updated the Kconfig entry to reflect this.
Also fixed a typo.
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
---
arch/powerpc/Kconfig.debug | 6 ++++--
arch/powerpc/mm/ptdump/ptdump.c | 21 ++++++++++++++++++++-
2 files changed, 24 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug
index ae084357994e..56e99e9a30d9 100644
--- a/arch/powerpc/Kconfig.debug
+++ b/arch/powerpc/Kconfig.debug
@@ -371,7 +371,7 @@ config PPC_PTDUMP
If you are unsure, say N.
config PPC_DEBUG_WX
- bool "Warn on W+X mappings at boot"
+ bool "Warn on W+X mappings at boot & enable manual checks at runtime"
depends on PPC_PTDUMP && STRICT_KERNEL_RWX
help
Generate a warning if any W+X mappings are found at boot.
@@ -385,7 +385,9 @@ config PPC_DEBUG_WX
of other unfixed kernel bugs easier.
There is no runtime or memory usage effect of this option
- once the kernel has booted up - it's a one time check.
+ once the kernel has booted up, it only automatically checks once.
+
+ Enables the "check_wx_pages" debugfs entry for checking at runtime.
If in doubt, say "Y".
diff --git a/arch/powerpc/mm/ptdump/ptdump.c b/arch/powerpc/mm/ptdump/ptdump.c
index aca354fb670b..78497d57b66b 100644
--- a/arch/powerpc/mm/ptdump/ptdump.c
+++ b/arch/powerpc/mm/ptdump/ptdump.c
@@ -4,7 +4,7 @@
*
* This traverses the kernel pagetables and dumps the
* information about the used sections of memory to
- * /sys/kernel/debug/kernel_pagetables.
+ * /sys/kernel/debug/kernel_page_tables.
*
* Derived from the arm64 implementation:
* Copyright (c) 2014, The Linux Foundation, Laura Abbott.
@@ -459,6 +459,25 @@ void ptdump_check_wx(void)
else
pr_info("Checked W+X mappings: passed, no W+X pages found\n");
}
+
+static int check_wx_debugfs_set(void *data, u64 val)
+{
+ if (val != 1ULL)
+ return -EINVAL;
+
+ ptdump_check_wx();
+
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(check_wx_fops, NULL, check_wx_debugfs_set, "%llu\n");
+
+static int ptdump_check_wx_init(void)
+{
+ return debugfs_create_file("check_wx_pages", 0200, NULL,
+ NULL, &check_wx_fops) ? 0 : -ENOMEM;
+}
+device_initcall(ptdump_check_wx_init);
#endif
static int ptdump_init(void)
--
2.25.1
^ permalink raw reply related
* [PATCH v9 3/8] powerpc/kprobes: Mark newly allocated probes as RO
From: Jordan Niethe @ 2021-03-16 3:17 UTC (permalink / raw)
To: linuxppc-dev
Cc: christophe.leroy, ajd, npiggin, naveen.n.rao, Jordan Niethe, dja
In-Reply-To: <20210316031741.1004850-1-jniethe5@gmail.com>
From: Russell Currey <ruscur@russell.cc>
With CONFIG_STRICT_KERNEL_RWX=y and CONFIG_KPROBES=y, there will be one
W+X page at boot by default. This can be tested with
CONFIG_PPC_PTDUMP=y and CONFIG_PPC_DEBUG_WX=y set, and checking the
kernel log during boot.
Add an arch specific insn page allocator which returns RO pages if
STRICT_KERNEL_RWX is enabled. This page is only written to with
patch_instruction() which is able to write RO pages.
Reviewed-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[jpn: Reword commit message, switch from vmalloc_exec(), add
free_insn_page()]
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
---
v9: - vmalloc_exec() no longer exists
- Set the page to RW before freeing it
---
arch/powerpc/kernel/kprobes.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c
index 01ab2163659e..bb7e4d321988 100644
--- a/arch/powerpc/kernel/kprobes.c
+++ b/arch/powerpc/kernel/kprobes.c
@@ -25,6 +25,8 @@
#include <asm/sections.h>
#include <asm/inst.h>
#include <linux/uaccess.h>
+#include <linux/set_memory.h>
+#include <linux/vmalloc.h>
DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
@@ -103,6 +105,26 @@ kprobe_opcode_t *kprobe_lookup_name(const char *name, unsigned int offset)
return addr;
}
+void *alloc_insn_page(void)
+{
+ void *page = vmalloc(PAGE_SIZE);
+
+ if (!page)
+ return NULL;
+
+ set_memory_ro((unsigned long)page, 1);
+ set_memory_x((unsigned long)page, 1);
+
+ return page;
+}
+
+void free_insn_page(void *page)
+{
+ set_memory_nx((unsigned long)page, 1);
+ set_memory_rw((unsigned long)page, 1);
+ vfree(page);
+}
+
int arch_prepare_kprobe(struct kprobe *p)
{
int ret = 0;
--
2.25.1
^ permalink raw reply related
* [PATCH v9 2/8] powerpc/lib/code-patching: Set up Strict RWX patching earlier
From: Jordan Niethe @ 2021-03-16 3:17 UTC (permalink / raw)
To: linuxppc-dev
Cc: christophe.leroy, ajd, npiggin, Jordan Niethe, naveen.n.rao, dja
In-Reply-To: <20210316031741.1004850-1-jniethe5@gmail.com>
setup_text_poke_area() is a late init call so it runs before
mark_rodata_ro() and after the init calls. This lets all the init code
patching simply write to their locations. In the future, kprobes is
going to allocate its instruction pages RO which means they will need
setup_text__poke_area() to have been already called for their code
patching. However, init_kprobes() (which allocates and patches some
instruction pages) is an early init call so it happens before
setup_text__poke_area().
start_kernel() calls poking_init() before any of the init calls. On
powerpc, poking_init() is currently a nop. setup_text_poke_area() relies
on kernel virtual memory, cpu hotplug and per_cpu_areas being setup.
setup_per_cpu_areas(), boot_cpu_hotplug_init() and mm_init() are called
before poking_init().
Turn setup_text_poke_area() into poking_init().
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
---
v9: New to series
---
arch/powerpc/lib/code-patching.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index 2333625b5e31..b28afa1133db 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -65,14 +65,11 @@ static int text_area_cpu_down(unsigned int cpu)
}
/*
- * Run as a late init call. This allows all the boot time patching to be done
- * simply by patching the code, and then we're called here prior to
- * mark_rodata_ro(), which happens after all init calls are run. Although
- * BUG_ON() is rude, in this case it should only happen if ENOMEM, and we judge
- * it as being preferable to a kernel that will crash later when someone tries
- * to use patch_instruction().
+ * Although BUG_ON() is rude, in this case it should only happen if ENOMEM, and
+ * we judge it as being preferable to a kernel that will crash later when
+ * someone tries to use patch_instruction().
*/
-static int __init setup_text_poke_area(void)
+int __init poking_init(void)
{
BUG_ON(!cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
"powerpc/text_poke:online", text_area_cpu_up,
@@ -80,7 +77,6 @@ static int __init setup_text_poke_area(void)
return 0;
}
-late_initcall(setup_text_poke_area);
/*
* This can be called for kernel text or a module.
--
2.25.1
^ permalink raw reply related
* [PATCH v9 1/8] powerpc/mm: Implement set_memory() routines
From: Jordan Niethe @ 2021-03-16 3:17 UTC (permalink / raw)
To: linuxppc-dev
Cc: christophe.leroy, ajd, npiggin, naveen.n.rao, Jordan Niethe, dja
From: Russell Currey <ruscur@russell.cc>
The set_memory_{ro/rw/nx/x}() functions are required for STRICT_MODULE_RWX,
and are generally useful primitives to have. This implementation is
designed to be completely generic across powerpc's many MMUs.
It's possible that this could be optimised to be faster for specific
MMUs, but the focus is on having a generic and safe implementation for
now.
This implementation does not handle cases where the caller is attempting
to change the mapping of the page it is executing from, or if another
CPU is concurrently using the page being altered. These cases likely
shouldn't happen, but a more complex implementation with MMU-specific code
could safely handle them, so that is left as a TODO for now.
These functions do nothing if STRICT_KERNEL_RWX is not enabled.
Reviewed-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[jpn: rebase on next plus "powerpc/mm/64s: Allow STRICT_KERNEL_RWX again"]
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/set_memory.h | 32 +++++++++++
arch/powerpc/mm/Makefile | 2 +-
arch/powerpc/mm/pageattr.c | 81 +++++++++++++++++++++++++++
4 files changed, 115 insertions(+), 1 deletion(-)
create mode 100644 arch/powerpc/include/asm/set_memory.h
create mode 100644 arch/powerpc/mm/pageattr.c
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index fc7f5c5933e6..4498a27ac9db 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -135,6 +135,7 @@ config PPC
select ARCH_HAS_MEMBARRIER_CALLBACKS
select ARCH_HAS_MEMBARRIER_SYNC_CORE
select ARCH_HAS_SCALED_CPUTIME if VIRT_CPU_ACCOUNTING_NATIVE && PPC_BOOK3S_64
+ select ARCH_HAS_SET_MEMORY
select ARCH_HAS_STRICT_KERNEL_RWX if ((PPC_BOOK3S_64 || PPC32) && !HIBERNATION)
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_HAS_UACCESS_FLUSHCACHE
diff --git a/arch/powerpc/include/asm/set_memory.h b/arch/powerpc/include/asm/set_memory.h
new file mode 100644
index 000000000000..64011ea444b4
--- /dev/null
+++ b/arch/powerpc/include/asm/set_memory.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_POWERPC_SET_MEMORY_H
+#define _ASM_POWERPC_SET_MEMORY_H
+
+#define SET_MEMORY_RO 0
+#define SET_MEMORY_RW 1
+#define SET_MEMORY_NX 2
+#define SET_MEMORY_X 3
+
+int change_memory_attr(unsigned long addr, int numpages, long action);
+
+static inline int set_memory_ro(unsigned long addr, int numpages)
+{
+ return change_memory_attr(addr, numpages, SET_MEMORY_RO);
+}
+
+static inline int set_memory_rw(unsigned long addr, int numpages)
+{
+ return change_memory_attr(addr, numpages, SET_MEMORY_RW);
+}
+
+static inline int set_memory_nx(unsigned long addr, int numpages)
+{
+ return change_memory_attr(addr, numpages, SET_MEMORY_NX);
+}
+
+static inline int set_memory_x(unsigned long addr, int numpages)
+{
+ return change_memory_attr(addr, numpages, SET_MEMORY_X);
+}
+
+#endif
diff --git a/arch/powerpc/mm/Makefile b/arch/powerpc/mm/Makefile
index 3b4e9e4e25ea..d8a08abde1ae 100644
--- a/arch/powerpc/mm/Makefile
+++ b/arch/powerpc/mm/Makefile
@@ -5,7 +5,7 @@
ccflags-$(CONFIG_PPC64) := $(NO_MINIMAL_TOC)
-obj-y := fault.o mem.o pgtable.o mmap.o maccess.o \
+obj-y := fault.o mem.o pgtable.o mmap.o maccess.o pageattr.o \
init_$(BITS).o pgtable_$(BITS).o \
pgtable-frag.o ioremap.o ioremap_$(BITS).o \
init-common.o mmu_context.o drmem.o
diff --git a/arch/powerpc/mm/pageattr.c b/arch/powerpc/mm/pageattr.c
new file mode 100644
index 000000000000..2da3fbab6ff7
--- /dev/null
+++ b/arch/powerpc/mm/pageattr.c
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * MMU-generic set_memory implementation for powerpc
+ *
+ * Copyright 2019, IBM Corporation.
+ */
+
+#include <linux/mm.h>
+#include <linux/set_memory.h>
+
+#include <asm/mmu.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+
+
+/*
+ * Updates the attributes of a page in three steps:
+ *
+ * 1. invalidate the page table entry
+ * 2. flush the TLB
+ * 3. install the new entry with the updated attributes
+ *
+ * This is unsafe if the caller is attempting to change the mapping of the
+ * page it is executing from, or if another CPU is concurrently using the
+ * page being altered.
+ *
+ * TODO make the implementation resistant to this.
+ *
+ * NOTE: can be dangerous to call without STRICT_KERNEL_RWX
+ */
+static int change_page_attr(pte_t *ptep, unsigned long addr, void *data)
+{
+ long action = (long)data;
+ pte_t pte;
+
+ spin_lock(&init_mm.page_table_lock);
+
+ /* invalidate the PTE so it's safe to modify */
+ pte = ptep_get_and_clear(&init_mm, addr, ptep);
+ flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
+
+ /* modify the PTE bits as desired, then apply */
+ switch (action) {
+ case SET_MEMORY_RO:
+ pte = pte_wrprotect(pte);
+ break;
+ case SET_MEMORY_RW:
+ pte = pte_mkwrite(pte);
+ break;
+ case SET_MEMORY_NX:
+ pte = pte_exprotect(pte);
+ break;
+ case SET_MEMORY_X:
+ pte = pte_mkexec(pte);
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ break;
+ }
+
+ set_pte_at(&init_mm, addr, ptep, pte);
+ spin_unlock(&init_mm.page_table_lock);
+
+ return 0;
+}
+
+int change_memory_attr(unsigned long addr, int numpages, long action)
+{
+ unsigned long start = ALIGN_DOWN(addr, PAGE_SIZE);
+ unsigned long sz = numpages * PAGE_SIZE;
+
+ if (!IS_ENABLED(CONFIG_STRICT_KERNEL_RWX))
+ return 0;
+
+ if (numpages <= 0)
+ return 0;
+
+ return apply_to_existing_page_range(&init_mm, start, sz,
+ change_page_attr, (void *)action);
+}
--
2.25.1
^ permalink raw reply related
* Re: [PATCH] ibmvfc: free channel_setup_buf during device tear down
From: Martin K. Petersen @ 2021-03-16 3:13 UTC (permalink / raw)
To: james.bottomley, Tyrel Datwyler
Cc: brking, linuxppc-dev, linux-kernel, Martin K . Petersen,
linux-scsi
In-Reply-To: <20210311012212.428068-1-tyreld@linux.ibm.com>
On Wed, 10 Mar 2021 19:22:12 -0600, Tyrel Datwyler wrote:
> The buffer for negotiating channel setup is DMA allocated at device
> probe time. However, the remove path fails to free this allocation which
> will prevent the hypervisor from releasing the virtual device in the
> case of a hotplug remove.
>
> Fix this issue by freeing the buffer allocation in ibmvfc_free_mem().
Applied to 5.12/scsi-fixes, thanks!
[1/1] ibmvfc: free channel_setup_buf during device tear down
https://git.kernel.org/mkp/scsi/c/febb0cc847e7
--
Martin K. Petersen Oracle Linux Engineering
^ permalink raw reply
* [powerpc:fixes-test] BUILD SUCCESS eed5fae00593ab9d261a0c1ffc1bdb786a87a55a
From: kernel test robot @ 2021-03-16 2:54 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev
tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git fixes-test
branch HEAD: eed5fae00593ab9d261a0c1ffc1bdb786a87a55a powerpc: Force inlining of cpu_has_feature() to avoid build failure
elapsed time: 2398m
configs tested: 187
configs skipped: 97
The following configs have been built successfully.
More configs may be tested in the coming days.
gcc tested configs:
arm defconfig
arm64 allyesconfig
arm64 defconfig
arm allyesconfig
arm allmodconfig
x86_64 allyesconfig
riscv allmodconfig
h8300 edosk2674_defconfig
powerpc amigaone_defconfig
powerpc linkstation_defconfig
m68k m5407c3_defconfig
arc nsimosci_hs_smp_defconfig
openrisc simple_smp_defconfig
sh defconfig
sh alldefconfig
powerpc taishan_defconfig
riscv nommu_k210_sdcard_defconfig
mips loongson3_defconfig
openrisc alldefconfig
sparc64 defconfig
m68k mac_defconfig
arm orion5x_defconfig
mips bcm63xx_defconfig
sh se7705_defconfig
powerpc bluestone_defconfig
sh rsk7264_defconfig
xtensa common_defconfig
arm zeus_defconfig
powerpc socrates_defconfig
m68k mvme16x_defconfig
riscv nommu_virt_defconfig
arc tb10x_defconfig
s390 alldefconfig
sh se7722_defconfig
powerpc cm5200_defconfig
h8300 alldefconfig
mips maltaaprp_defconfig
mips rt305x_defconfig
mips xway_defconfig
powerpc ppc6xx_defconfig
powerpc tqm8555_defconfig
powerpc tqm8541_defconfig
sh polaris_defconfig
sh espt_defconfig
arm stm32_defconfig
arm s5pv210_defconfig
arm aspeed_g4_defconfig
mips workpad_defconfig
mips rm200_defconfig
powerpc ppc44x_defconfig
sh titan_defconfig
m68k sun3x_defconfig
mips jmr3927_defconfig
sh ecovec24_defconfig
sh ap325rxa_defconfig
mips cu1000-neo_defconfig
arm versatile_defconfig
arm lpc32xx_defconfig
sh shmin_defconfig
mips ip32_defconfig
arm qcom_defconfig
ia64 defconfig
mips gpr_defconfig
mips decstation_64_defconfig
powerpc tqm8xx_defconfig
xtensa virt_defconfig
arm eseries_pxa_defconfig
m68k bvme6000_defconfig
powerpc rainier_defconfig
parisc generic-32bit_defconfig
arm mini2440_defconfig
i386 defconfig
powerpc kmeter1_defconfig
powerpc mpc5200_defconfig
mips fuloong2e_defconfig
parisc generic-64bit_defconfig
arm hisi_defconfig
powerpc mpc836x_mds_defconfig
arc haps_hs_smp_defconfig
sh se7712_defconfig
powerpc mpc512x_defconfig
ia64 alldefconfig
csky defconfig
arc alldefconfig
arm viper_defconfig
mips lemote2f_defconfig
arc nsimosci_defconfig
powerpc mpc837x_rdb_defconfig
parisc defconfig
openrisc defconfig
powerpc storcenter_defconfig
microblaze mmu_defconfig
mips ip22_defconfig
sh edosk7760_defconfig
arc vdk_hs38_smp_defconfig
arm s3c2410_defconfig
powerpc motionpro_defconfig
arm h3600_defconfig
powerpc mpc8313_rdb_defconfig
powerpc g5_defconfig
ia64 allmodconfig
ia64 allyesconfig
m68k allmodconfig
m68k defconfig
m68k allyesconfig
nios2 defconfig
arc allyesconfig
nds32 allnoconfig
nds32 defconfig
nios2 allyesconfig
alpha defconfig
alpha allyesconfig
xtensa allyesconfig
h8300 allyesconfig
arc defconfig
sh allmodconfig
s390 allyesconfig
s390 allmodconfig
parisc allyesconfig
s390 defconfig
i386 allyesconfig
sparc allyesconfig
sparc defconfig
i386 tinyconfig
mips allyesconfig
mips allmodconfig
powerpc allyesconfig
powerpc allmodconfig
powerpc allnoconfig
x86_64 randconfig-a006-20210315
x86_64 randconfig-a001-20210315
x86_64 randconfig-a005-20210315
x86_64 randconfig-a004-20210315
x86_64 randconfig-a002-20210315
x86_64 randconfig-a003-20210315
i386 randconfig-a001-20210314
i386 randconfig-a005-20210314
i386 randconfig-a003-20210314
i386 randconfig-a002-20210314
i386 randconfig-a004-20210314
i386 randconfig-a006-20210314
i386 randconfig-a001-20210315
i386 randconfig-a005-20210315
i386 randconfig-a003-20210315
i386 randconfig-a002-20210315
i386 randconfig-a004-20210315
i386 randconfig-a006-20210315
x86_64 randconfig-a011-20210314
x86_64 randconfig-a016-20210314
x86_64 randconfig-a013-20210314
x86_64 randconfig-a015-20210314
x86_64 randconfig-a014-20210314
x86_64 randconfig-a012-20210314
i386 randconfig-a013-20210314
i386 randconfig-a016-20210314
i386 randconfig-a011-20210314
i386 randconfig-a012-20210314
i386 randconfig-a014-20210314
i386 randconfig-a015-20210314
i386 randconfig-a013-20210315
i386 randconfig-a016-20210315
i386 randconfig-a011-20210315
i386 randconfig-a012-20210315
i386 randconfig-a014-20210315
i386 randconfig-a015-20210315
riscv nommu_k210_defconfig
riscv allyesconfig
riscv allnoconfig
riscv defconfig
riscv rv32_defconfig
x86_64 rhel-7.6-kselftests
x86_64 defconfig
x86_64 rhel-8.3
x86_64 rhel-8.3-kbuiltin
x86_64 kexec
clang tested configs:
x86_64 randconfig-a006-20210314
x86_64 randconfig-a001-20210314
x86_64 randconfig-a005-20210314
x86_64 randconfig-a004-20210314
x86_64 randconfig-a002-20210314
x86_64 randconfig-a003-20210314
x86_64 randconfig-a016-20210315
x86_64 randconfig-a015-20210315
x86_64 randconfig-a014-20210315
x86_64 randconfig-a011-20210315
x86_64 randconfig-a013-20210315
x86_64 randconfig-a012-20210315
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
^ permalink raw reply
* [powerpc:next-test] BUILD SUCCESS 1e97f67cc191d74dfacb2a6f4a4ad1db2682a036
From: kernel test robot @ 2021-03-16 2:54 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev
tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next-test
branch HEAD: 1e97f67cc191d74dfacb2a6f4a4ad1db2682a036 powerpc/fsl-pci: Fix section mismatch warning
elapsed time: 739m
configs tested: 135
configs skipped: 3
The following configs have been built successfully.
More configs may be tested in the coming days.
gcc tested configs:
arm defconfig
arm64 allyesconfig
arm64 defconfig
arm allyesconfig
arm allmodconfig
x86_64 allyesconfig
riscv allmodconfig
h8300 edosk2674_defconfig
powerpc amigaone_defconfig
powerpc linkstation_defconfig
m68k m5407c3_defconfig
arc nsimosci_hs_smp_defconfig
openrisc simple_smp_defconfig
mips malta_kvm_defconfig
arm exynos_defconfig
ia64 bigsur_defconfig
arm dove_defconfig
openrisc alldefconfig
sparc64 defconfig
m68k mac_defconfig
arm orion5x_defconfig
mips bcm63xx_defconfig
nds32 alldefconfig
arc axs103_smp_defconfig
arm u8500_defconfig
powerpc ppc6xx_defconfig
powerpc mpc7448_hpc2_defconfig
sh ap325rxa_defconfig
mips cu1000-neo_defconfig
mips xway_defconfig
arm versatile_defconfig
arm lpc32xx_defconfig
sh shmin_defconfig
mips ip32_defconfig
parisc alldefconfig
ia64 defconfig
sh se7712_defconfig
arm lubbock_defconfig
x86_64 defconfig
sh rts7751r2dplus_defconfig
powerpc tqm8xx_defconfig
xtensa virt_defconfig
sh se7722_defconfig
arm eseries_pxa_defconfig
m68k bvme6000_defconfig
powerpc rainier_defconfig
parisc generic-32bit_defconfig
arm mini2440_defconfig
powerpc mpc5200_defconfig
mips fuloong2e_defconfig
parisc generic-64bit_defconfig
arm hisi_defconfig
powerpc mpc836x_mds_defconfig
mips rt305x_defconfig
arc haps_hs_smp_defconfig
csky defconfig
powerpc mpc512x_defconfig
ia64 alldefconfig
powerpc sam440ep_defconfig
sh sh7763rdp_defconfig
um i386_defconfig
ia64 allyesconfig
sh sh7757lcr_defconfig
arm s3c6400_defconfig
arc tb10x_defconfig
mips e55_defconfig
m68k defconfig
powerpc motionpro_defconfig
arm h3600_defconfig
powerpc mpc8313_rdb_defconfig
powerpc g5_defconfig
powerpc mpc837x_rdb_defconfig
ia64 allmodconfig
m68k allmodconfig
m68k allyesconfig
nios2 defconfig
arc allyesconfig
nds32 allnoconfig
nds32 defconfig
nios2 allyesconfig
alpha defconfig
alpha allyesconfig
xtensa allyesconfig
h8300 allyesconfig
arc defconfig
sh allmodconfig
parisc defconfig
s390 allyesconfig
s390 allmodconfig
parisc allyesconfig
s390 defconfig
i386 allyesconfig
sparc allyesconfig
sparc defconfig
i386 tinyconfig
i386 defconfig
mips allyesconfig
mips allmodconfig
powerpc allyesconfig
powerpc allmodconfig
powerpc allnoconfig
x86_64 randconfig-a006-20210315
x86_64 randconfig-a001-20210315
x86_64 randconfig-a005-20210315
x86_64 randconfig-a004-20210315
x86_64 randconfig-a002-20210315
x86_64 randconfig-a003-20210315
i386 randconfig-a001-20210315
i386 randconfig-a005-20210315
i386 randconfig-a003-20210315
i386 randconfig-a002-20210315
i386 randconfig-a004-20210315
i386 randconfig-a006-20210315
i386 randconfig-a013-20210315
i386 randconfig-a016-20210315
i386 randconfig-a011-20210315
i386 randconfig-a012-20210315
i386 randconfig-a014-20210315
i386 randconfig-a015-20210315
riscv nommu_k210_defconfig
riscv allyesconfig
riscv nommu_virt_defconfig
riscv allnoconfig
riscv defconfig
riscv rv32_defconfig
x86_64 rhel-7.6-kselftests
x86_64 rhel-8.3
x86_64 rhel-8.3-kbuiltin
x86_64 kexec
clang tested configs:
x86_64 randconfig-a011-20210315
x86_64 randconfig-a016-20210315
x86_64 randconfig-a013-20210315
x86_64 randconfig-a015-20210315
x86_64 randconfig-a014-20210315
x86_64 randconfig-a012-20210315
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
^ permalink raw reply
* [powerpc:merge] BUILD SUCCESS 0512161accb8b6f6dacc85d165350b1812ddcc33
From: kernel test robot @ 2021-03-16 2:54 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev
tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git merge
branch HEAD: 0512161accb8b6f6dacc85d165350b1812ddcc33 Automatic merge of 'fixes' into merge (2021-03-16 00:24)
elapsed time: 741m
configs tested: 137
configs skipped: 3
The following configs have been built successfully.
More configs may be tested in the coming days.
gcc tested configs:
arm defconfig
arm64 allyesconfig
arm64 defconfig
arm allyesconfig
arm allmodconfig
x86_64 allyesconfig
riscv allmodconfig
h8300 edosk2674_defconfig
powerpc amigaone_defconfig
powerpc linkstation_defconfig
m68k m5407c3_defconfig
arc nsimosci_hs_smp_defconfig
openrisc simple_smp_defconfig
mips malta_kvm_defconfig
arm exynos_defconfig
ia64 bigsur_defconfig
arm dove_defconfig
openrisc alldefconfig
sparc64 defconfig
m68k mac_defconfig
arm orion5x_defconfig
mips bcm63xx_defconfig
arm zeus_defconfig
powerpc socrates_defconfig
m68k mvme16x_defconfig
riscv nommu_virt_defconfig
arc tb10x_defconfig
s390 alldefconfig
xtensa virt_defconfig
ia64 defconfig
mips cu1000-neo_defconfig
sparc alldefconfig
mips rs90_defconfig
mips ip32_defconfig
sh ap325rxa_defconfig
mips xway_defconfig
arm versatile_defconfig
arm lpc32xx_defconfig
sh shmin_defconfig
powerpc tqm8xx_defconfig
sh se7722_defconfig
arm eseries_pxa_defconfig
m68k bvme6000_defconfig
powerpc rainier_defconfig
parisc generic-32bit_defconfig
arm mini2440_defconfig
i386 defconfig
h8300 allyesconfig
h8300 h8s-sim_defconfig
sh r7785rp_defconfig
mips maltaup_defconfig
sh apsh4ad0a_defconfig
sh se7721_defconfig
powerpc mpc5200_defconfig
mips fuloong2e_defconfig
parisc generic-64bit_defconfig
arm hisi_defconfig
powerpc mpc836x_mds_defconfig
mips rt305x_defconfig
arc haps_hs_smp_defconfig
sh se7712_defconfig
powerpc mpc512x_defconfig
ia64 alldefconfig
csky defconfig
arm colibri_pxa300_defconfig
sh se7751_defconfig
m68k m5208evb_defconfig
arm aspeed_g5_defconfig
arm netwinder_defconfig
parisc allyesconfig
powerpc motionpro_defconfig
arm h3600_defconfig
powerpc mpc8313_rdb_defconfig
powerpc g5_defconfig
powerpc mpc837x_rdb_defconfig
ia64 allmodconfig
ia64 allyesconfig
m68k allmodconfig
m68k defconfig
m68k allyesconfig
nios2 defconfig
arc allyesconfig
nds32 allnoconfig
nds32 defconfig
nios2 allyesconfig
alpha defconfig
alpha allyesconfig
xtensa allyesconfig
arc defconfig
sh allmodconfig
parisc defconfig
s390 allyesconfig
s390 allmodconfig
s390 defconfig
i386 allyesconfig
sparc allyesconfig
sparc defconfig
i386 tinyconfig
mips allyesconfig
mips allmodconfig
powerpc allyesconfig
powerpc allmodconfig
powerpc allnoconfig
x86_64 randconfig-a006-20210315
x86_64 randconfig-a001-20210315
x86_64 randconfig-a005-20210315
x86_64 randconfig-a004-20210315
x86_64 randconfig-a002-20210315
x86_64 randconfig-a003-20210315
i386 randconfig-a001-20210315
i386 randconfig-a005-20210315
i386 randconfig-a003-20210315
i386 randconfig-a002-20210315
i386 randconfig-a004-20210315
i386 randconfig-a006-20210315
i386 randconfig-a013-20210315
i386 randconfig-a016-20210315
i386 randconfig-a011-20210315
i386 randconfig-a012-20210315
i386 randconfig-a014-20210315
i386 randconfig-a015-20210315
riscv nommu_k210_defconfig
riscv allyesconfig
riscv allnoconfig
riscv defconfig
riscv rv32_defconfig
x86_64 rhel-7.6-kselftests
x86_64 defconfig
x86_64 rhel-8.3
x86_64 rhel-8.3-kbuiltin
x86_64 kexec
clang tested configs:
x86_64 randconfig-a011-20210315
x86_64 randconfig-a016-20210315
x86_64 randconfig-a013-20210315
x86_64 randconfig-a015-20210315
x86_64 randconfig-a014-20210315
x86_64 randconfig-a012-20210315
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
^ permalink raw reply
* Re: [PATCH] powerpc/kexec: Don't use .machine ppc64 in trampoline_64.S
From: Segher Boessenkool @ 2021-03-16 2:44 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev, dja
In-Reply-To: <20210315034159.315675-1-mpe@ellerman.id.au>
Hi!
On Mon, Mar 15, 2021 at 02:41:59PM +1100, Michael Ellerman wrote:
> The ".machine" directive allows changing the machine for which code is
> being generated. It's equivalent to passing an -mcpu option on the
> command line.
>
> Although it can be useful, it's generally a bad idea because it adds
> another way to influence code generation separate from the flags
> passed via the build system. ie. if we need to build different pieces
> of code with different flags we should do that via our Makefiles, not
> using ".machine".
It does not influence code generation. It says which instructions are
valid, instead. There are a few cases where the same mnemonic will
generate a different binary encoding depending on machine selected,
maybe you mean that?
It is *normal* to use .machine push/pop and a specific .machine around
instructions that require a machine other than what you are building
for. The compiler does this itself, and it is the recommended way to
use "foreign" instructions in inline assembler.
That said...
> However as best as I can tell the ".machine" directive in
> trampoline_64.S is not necessary at all.
>
> It was added in commit 0d97631392c2 ("powerpc: Add purgatory for
> kexec_file_load() implementation."), which created the file based on
> the kexec-tools purgatory. It may be/have-been necessary in the
> kexec-tools version, but we have a completely different build system,
> and we already pass the desired CPU flags, eg:
>
> gcc ... -m64 -Wl,-a64 -mabi=elfv2 -Wa,-maltivec -Wa,-mpower4 -Wa,-many
> ... arch/powerpc/purgatory/trampoline_64.S
>
> So drop the ".machine" directive and rely on the assembler flags.
> - .machine ppc64
Please make sure to test this on a big endian config.
A ppc64le-linux assembler defaults to power8. A ppc64-linux assembler
defaults to power3 (that is the same as .machine ppc64). Or maybe it
makes it power4? I get lost :-)
It certainly *should* work, but, test please :-)
(And with a *default* powerpc64-linux config, not one that defaults to
power7 or power8 or similar! Arnd's toolchains at
<https://mirrors.edge.kernel.org/pub/tools/crosstool/>
are fine for this.)
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Segher
^ permalink raw reply
* Re: [PATCH 0/2] handle premature return from H_JOIN in pseries mobility code
From: Nicholas Piggin @ 2021-03-16 2:37 UTC (permalink / raw)
To: linuxppc-dev, Nathan Lynch; +Cc: brking, tyreld
In-Reply-To: <20210315080045.460331-1-nathanl@linux.ibm.com>
Excerpts from Nathan Lynch's message of March 15, 2021 6:00 pm:
> pseries VMs in shared processor mode are susceptible to failed
> migrations becasue stray H_PRODs from the paravirt spinlock
> implementation can bump threads out of joining state before the
> suspend has occurred. Fix this by adding a small amount of shared
> state and ordering accesses to it with respect to H_PROD and H_JOIN.
Oh, tricky problem. Nice work on finding and fixing it.
The patches seem okay to me.
Thanks,
Nick
^ permalink raw reply
* Re: [PATCH] powerpc: Fix missing prototype problems for "arch/powerpc/kernel/setup_64.c"
From: heying (H) @ 2021-03-16 2:04 UTC (permalink / raw)
To: Cédric Le Goater, Christophe Leroy, mpe, benh, paulus,
npiggin, dja, akpm, rppt, aneesh.kumar
Cc: johnny.chenyi, linuxppc-dev
In-Reply-To: <eb78b1b0-03f9-2b20-02a7-74dbeea81493@kaod.org>
Dear Cédric Le Goater and Christophe Leroy,
Thanks for all your suggestions! I'll pick them in my patch and resent
it soon.
Thanks again.
在 2021/3/15 21:14, Cédric Le Goater 写道:
> On 3/15/21 2:01 PM, Christophe Leroy wrote:
>>
>> Le 15/03/2021 à 13:57, Cédric Le Goater a écrit :
>>> On 3/15/21 1:48 PM, heying (H) wrote:
>>>> 在 2021/3/15 20:17, Christophe Leroy 写道:
>>>>> You subject doesn't match the content of the patch.
>>>> OK. I'll adapt that.
>>>>> Le 15/03/2021 à 13:04, He Ying a écrit :
>>>>>> The variables 'uaccess_fulsh' and 'entry_flush' are not referenced
>>>>>> outside the file. So define them as static to avoid the warnings.
>>>>>>
>>>>>> And add a prototype for the function 'panic_smp_self_stop' for the
>>>>>> same purpose.
>>>>>>
>>>>>> Sparse also warns that 'rfi_flush' should be static. However, it's
>>>>>> referenced outside the file.
>>>>> To clear that warning, you have to include asm/security_features.h, rfi_flush is declared there.
>>>> Do you mean that I should include this header in arch/powerpc/kernel/setup_64.c?
>>> yes.
>>>
>>>>>> The warnings about the file reported by sparse are as follows:
>>>>>> arch/powerpc/kernel/setup_64.c:422:6: warning: symbol 'panic_smp_self_stop' was not declared. Should it be static?
>>>>>> arch/powerpc/kernel/setup_64.c:951:6: warning: symbol 'rfi_flush' was not declared. Should it be static?
>>>>>> arch/powerpc/kernel/setup_64.c:952:6: warning: symbol 'entry_flush' was not declared. Should it be static?
>>>>>> arch/powerpc/kernel/setup_64.c:953:6: warning: symbol 'uaccess_flush' was not declared. Should it be static?
>>>>>>
>>>>>> Reported-by: Hulk Robot <hulkci@huawei.com>
>>>>>> Signed-off-by: He Ying <heying24@huawei.com>
>>>>>> ---
>>>>>> arch/powerpc/kernel/setup_64.c | 6 ++++--
>>>>>> 1 file changed, 4 insertions(+), 2 deletions(-)
>>>>>>
>>>>>> diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
>>>>>> index 560ed8b975e7..603aacd8527b 100644
>>>>>> --- a/arch/powerpc/kernel/setup_64.c
>>>>>> +++ b/arch/powerpc/kernel/setup_64.c
>>>>>> @@ -71,6 +71,8 @@
>>>>>> #include "setup.h"
>>>>>> +extern void panic_smp_self_stop(void);
>>>>>> +
>>>>> For function prototypes 'extern' is unneeded and deprecated.
>>>>>
>>>>> And function prototypes should go in an header file.
>>>>>
>>>>> panic_smp_self_stop() is called from kernel/panic.c , it should be declared in one of the generic linux header files I think.
>>>> Yes, you're right. But I have no idea which header it should be declared in. May I have your suggestions?
>>> arch/powerpc/include/asm/bug.h looks like a good place.
>> Why declaring it in a powerpc header ?
>>
>> It's a weak function defined in core part of kernel (kernel/panic.c).
>>
>> I think it should go in a common header, just like for instance arch_thaw_secondary_cpus_begin()
> Indeed. include/linux/smp.h is a better place for a common routine.
>
> C.
>
> .
^ permalink raw reply
* Re: VIO bus not initialized
From: Michael Ellerman @ 2021-03-16 1:10 UTC (permalink / raw)
To: Paul Menzel, Benjamin Herrenschmidt, Paul Mackerras; +Cc: linuxppc-dev
In-Reply-To: <90e6a559-0908-684c-9156-5f3da2b02e38@molgen.mpg.de>
Paul Menzel <pmenzel@molgen.mpg.de> writes:
> Am 15.03.21 um 08:53 schrieb Michael Ellerman:
>> Paul Menzel writes:
>
>>> On the POWER8 system IBM S822LC, Linux 5.12-rc2+ logs the errors below.
>>
>> That's a bare metal system, you can see that from the line "Using
>> PowerNV machine description" in the boot log.
>>
>>> $ dmesg --level=err
>>> [ 1.555668] Driver 'hvc_console' was unable to register with bus_type 'vio' because the bus was not initialized.
>>> [ 1.558434] Driver 'tpm_ibmvtpm' was unable to register with bus_type 'vio' because the bus was not initialized.
>>> $ grep VIO /boot/config-5.12.0-rc2+
>>> CONFIG_IBMVIO=y
>>
>> The "vio" bus is not a real bus, it's a fake bus we use for hypervisor
>> provided devices in LPARs (guests).
>>
>> So on bare metal machines there is no vio bus, the devices that would
>> appear on the vio bus are found via other mechanisms.
>
> Thank you for the explanation. Two questions:
>
> 1. Could a bare metal system be detected, and the VIO “be skipped”?
Yeah, in fact we are already skipping the registration of the bus,
that's why we're seeing these messages. We need to also skip the
registration of the drivers to avoid those warnings.
See the patch I just sent.
cheers
^ permalink raw reply
* [PATCH] powerpc/pseries: Only register vio drivers if vio bus exists
From: Michael Ellerman @ 2021-03-16 1:09 UTC (permalink / raw)
To: linuxppc-dev; +Cc: pmenzel
The vio bus is a fake bus, which we use on pseries LPARs (guests) to
discover devices provided by the hypervisor. There's no need or sense
in creating the vio bus on bare metal systems.
Which is why commit 4336b9337824 ("powerpc/pseries: Make vio and
ibmebus initcalls pseries specific") made the initialisation of the
vio bus only happen in LPARs.
However as a result of that commit we now see errors at boot on bare
metal systems:
Driver 'hvc_console' was unable to register with bus_type 'vio' because the bus was not initialized.
Driver 'tpm_ibmvtpm' was unable to register with bus_type 'vio' because the bus was not initialized.
This happens because those drivers are built-in, and are calling
vio_register_driver(). It in turn calls driver_register() with a
reference to vio_bus_type, but we haven't registered vio_bus_type with
the driver core.
Fix it by also guarding vio_register_driver() with a check to see if
we are on pseries.
Fixes: 4336b9337824 ("powerpc/pseries: Make vio and ibmebus initcalls pseries specific")
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
arch/powerpc/platforms/pseries/vio.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/powerpc/platforms/pseries/vio.c b/arch/powerpc/platforms/pseries/vio.c
index 9cb4fc839fd5..429053d0402a 100644
--- a/arch/powerpc/platforms/pseries/vio.c
+++ b/arch/powerpc/platforms/pseries/vio.c
@@ -1285,6 +1285,10 @@ static int vio_bus_remove(struct device *dev)
int __vio_register_driver(struct vio_driver *viodrv, struct module *owner,
const char *mod_name)
{
+ // vio_bus_type is only initialised for pseries
+ if (!machine_is(pseries))
+ return -ENODEV;
+
pr_debug("%s: driver %s registering\n", __func__, viodrv->name);
/* fill in 'struct driver' fields */
--
2.25.1
^ permalink raw reply related
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