* Re: [PATCH 2/2] ASoC: fsl: imx-es8328: add missing put_device() call in imx_es8328_probe()
From: Marco Felsch @ 2020-08-27 9:17 UTC (permalink / raw)
To: Yu Kuai
Cc: linux-arm-kernel, alsa-devel, linuxppc-dev, timur, Xiubo.Lee,
yi.zhang, festevam, s.hauer, tiwai, lgirdwood, perex,
nicoleotsuka, broonie, linux-imx, kernel, yukuai, shawnguo, xobs,
shengjiu.wang, linux-kernel
In-Reply-To: <20200825120531.1479304-3-yukuai3@huawei.com>
On 20-08-25 20:05, Yu Kuai wrote:
> if of_find_device_by_node() succeed, imx_es8328_probe() doesn't have
> a corresponding put_device().
Why do we need the ssi_pdev reference here at all?
Regards,
Marco
^ permalink raw reply
* Re: kernel since 5.6 do not boot anymore on Apple PowerBook
From: Christophe Leroy @ 2020-08-27 10:39 UTC (permalink / raw)
To: Giuseppe Sacco, linuxppc-dev
In-Reply-To: <cab15033beeefa317aae40370664e108f57dc050.camel@sguazz.it>
Hi,
Le 27/08/2020 à 10:28, Giuseppe Sacco a écrit :
> Il giorno gio, 27/08/2020 alle 09.46 +0200, Giuseppe Sacco ha scritto:
>> Il giorno gio, 27/08/2020 alle 00.28 +0200, Giuseppe Sacco ha scritto:
>>> Hello Christophe,
>>>
>>> Il giorno mer, 26/08/2020 alle 15.53 +0200, Christophe Leroy ha
>>> scritto:
>>> [...]
>>>> If there is no warning, then the issue is something else, bad luck.
>>>>
>>>> Could you increase the loglevel and try again both with and without
>>>> VMAP_STACK ? Maybe we'll get more information on where it stops.
>>>
>>> The problem is related to the CPU frequency changes. This is where the
>>> system stop: cpufreq get the CPU frequency limits and then start the
>>> default governor (performance) and then calls function
>>> cpufreq_gov_performance_limits() that never returns.
>>>
>>> Rebuilding after enabling pr_debug for cpufreq.c, I've got some more
>>> lines of output:
>>>
>>> cpufreq: setting new policy for CPU 0: 667000 - 867000 kHz
>>> cpufreq: new min and max freqs are 667000 - 867000 kHz
>>> cpufreq: governor switch
>>> cpufreq: cpufreq_init_governor: for CPU 0
>>> cpufreq: cpufreq_start_governor: for CPU 0
>>> cpufreq: target for CPU 0: 867000 kHz, relation 1, requested 867000 kHz
>>> cpufreq: __target_index: cpu: 0, oldfreq: 667000, new freq: 867000
>>> cpufreq: notification 0 of frequency transition to 867000 kHz
>>> cpufreq: saving 133328 as reference value for loops_per_jiffy; freq is 667000 kHz
>>>
>>> no more lines are printed. I think this output only refers to the
>>> notification sent prior to the frequency change.
>>>
>>> I was thinking that selecting a governor that would run at 667mHz would
>>> probably skip the problem. I added cpufreq.default_governor=powersave
>>> to the command line parameters but it did not work: the selected
>>> governor was still performance and the system crashed.
>>
>> I kept following the thread and found that CPU frequency is changed in
>> function pmu_set_cpu_speed() in file drivers/cpufreq/pmac32-cpufreq.c.
>> As first thing, the function calls the macro preempt_disable() and this
>> is where it stops.
>
> Sorry, I made a mistake. The real problem is down, on the same
> function, when it calls low_sleep_handler(). This is where the problem
> probably is.
>
Great, you spotted the problem.
I see what it is, it is in low_sleep_handler() in
arch/powerpc/platforms/powermac/sleep.S
All critical registers are saved on the stack. At restore, they are
restore BEFORE re-enabling MMU (because they are needed for that). But
when we have VMAP_STACK, the stack can hardly be accessed without the
MMU enabled. tophys() doesn't work for virtual stack addresses.
Therefore, the low_sleep_handler() has to be reworked for using an area
in the linear mem instead of the stack.
Christophe
^ permalink raw reply
* Re: [PATCH v3 3/6] Add LKDTM test to hijack a patch mapping (powerpc, x86_64)
From: kernel test robot @ 2020-08-27 10:11 UTC (permalink / raw)
To: Christopher M. Riedl, linuxppc-dev; +Cc: kbuild-all, kernel-hardening
In-Reply-To: <20200827052659.24922-4-cmr@codefail.de>
[-- Attachment #1: Type: text/plain, Size: 4191 bytes --]
Hi "Christopher,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on powerpc/next]
[also build test ERROR on char-misc/char-misc-testing tip/x86/core v5.9-rc2 next-20200827]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Christopher-M-Riedl/Use-per-CPU-temporary-mappings-for-patching/20200827-161532
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: x86_64-allmodconfig (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce (this is a W=1 build):
# save the attached .config to linux build tree
make W=1 ARCH=x86_64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
drivers/misc/lkdtm/perms.c: In function 'lkdtm_HIJACK_PATCH':
>> drivers/misc/lkdtm/perms.c:318:38: error: implicit declaration of function 'read_cpu_patching_addr' [-Werror=implicit-function-declaration]
318 | addr = offset_in_page(patch_site) | read_cpu_patching_addr(patching_cpu);
| ^~~~~~~~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
# https://github.com/0day-ci/linux/commit/36a98d779ee4620e6e091cbe3b438b52faa108ad
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Christopher-M-Riedl/Use-per-CPU-temporary-mappings-for-patching/20200827-161532
git checkout 36a98d779ee4620e6e091cbe3b438b52faa108ad
vim +/read_cpu_patching_addr +318 drivers/misc/lkdtm/perms.c
289
290 void lkdtm_HIJACK_PATCH(void)
291 {
292 #ifdef CONFIG_PPC
293 struct ppc_inst original_insn = ppc_inst_read(READ_ONCE(patch_site));
294 #endif
295 #ifdef CONFIG_X86_64
296 int original_insn = READ_ONCE(*patch_site);
297 #endif
298 struct task_struct *patching_kthrd;
299 int patching_cpu, hijacker_cpu, attempts;
300 unsigned long addr;
301 bool hijacked;
302 const int bad_data = 0xbad00bad;
303
304 if (num_online_cpus() < 2) {
305 pr_warn("need at least two cpus\n");
306 return;
307 }
308
309 hijacker_cpu = smp_processor_id();
310 patching_cpu = cpumask_any_but(cpu_online_mask, hijacker_cpu);
311
312 patching_kthrd = kthread_create_on_node(&lkdtm_patching_cpu, NULL,
313 cpu_to_node(patching_cpu),
314 "lkdtm_patching_cpu");
315 kthread_bind(patching_kthrd, patching_cpu);
316 wake_up_process(patching_kthrd);
317
> 318 addr = offset_in_page(patch_site) | read_cpu_patching_addr(patching_cpu);
319
320 pr_info("starting hijacker_cpu=%d\n", hijacker_cpu);
321 for (attempts = 0; attempts < 100000; ++attempts) {
322 /* Use __put_user to catch faults without an Oops */
323 hijacked = !__put_user(bad_data, (int *)addr);
324
325 if (hijacked) {
326 if (kthread_stop(patching_kthrd))
327 pr_err("error trying to stop patching thread\n");
328 break;
329 }
330 }
331 pr_info("hijack attempts: %d\n", attempts);
332
333 if (hijacked) {
334 if (lkdtm_verify_patch(bad_data))
335 pr_err("overwrote kernel text\n");
336 /*
337 * There are window conditions where the hijacker cpu manages to
338 * write to the patch site but the site gets overwritten again by
339 * the patching cpu. We still consider that a "successful" hijack
340 * since the hijacker cpu did not fault on the write.
341 */
342 pr_err("FAIL: wrote to another cpu's patching area\n");
343 } else {
344 kthread_stop(patching_kthrd);
345 }
346
347 /* Restore the original insn for any future lkdtm tests */
348 #ifdef CONFIG_PPC
349 patch_instruction(patch_site, original_insn);
350 #endif
351 #ifdef CONFIG_X86_64
352 lkdtm_do_patch(original_insn);
353 #endif
354 }
355
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 76556 bytes --]
^ permalink raw reply
* Re: [PATCH 09/11] x86: remove address space overrides using set_fs()
From: 'Christoph Hellwig' @ 2020-08-27 9:37 UTC (permalink / raw)
To: David Laight
Cc: linux-arch@vger.kernel.org, Kees Cook, x86@kernel.org,
linux-kernel@vger.kernel.org, Al Viro,
linux-fsdevel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
'Christoph Hellwig'
In-Reply-To: <935d551809894d14965e430e05d21057@AcuMS.aculab.com>
On Mon, Aug 17, 2020 at 08:23:11AM +0000, David Laight wrote:
> From: Christoph Hellwig
> > Sent: 17 August 2020 08:32
> >
> > Stop providing the possibility to override the address space using
> > set_fs() now that there is no need for that any more. To properly
> > handle the TASK_SIZE_MAX checking for 4 vs 5-level page tables on
> > x86 a new alternative is introduced, which just like the one in
> > entry_64.S has to use the hardcoded virtual address bits to escape
> > the fact that TASK_SIZE_MAX isn't actually a constant when 5-level
> > page tables are enabled.
> ....
> > @@ -93,7 +69,7 @@ static inline bool pagefault_disabled(void);
> > #define access_ok(addr, size) \
> > ({ \
> > WARN_ON_IN_IRQ(); \
> > - likely(!__range_not_ok(addr, size, user_addr_max())); \
> > + likely(!__range_not_ok(addr, size, TASK_SIZE_MAX)); \
> > })
>
> Can't that always compare against a constant even when 5-levl
> page tables are enabled on x86-64?
>
> On x86-64 it can (probably) reduce to (addr | (addr + size)) < 0.
I'll leave that to the x86 maintainers as a future cleanup if wanted.
^ permalink raw reply
* Re: [PATCHv5 1/2] powerpc/pseries: group lmb operation and memblock's
From: Laurent Dufour @ 2020-08-27 8:53 UTC (permalink / raw)
To: Pingfan Liu, linuxppc-dev
Cc: Nathan Lynch, kexec, Hari Bathini, Nathan Fontenot
In-Reply-To: <1597049570-19536-1-git-send-email-kernelfans@gmail.com>
Le 10/08/2020 à 10:52, Pingfan Liu a écrit :
> This patch prepares for the incoming patch which swaps the order of
> KOBJ_ADD/REMOVE uevent and dt's updating.
>
> The dt updating should come after lmb operations, and before
> __remove_memory()/__add_memory(). Accordingly, grouping all lmb operations
> before the memblock's.
I can't find the link between this commit description and the code's changes below.
>
> Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Hari Bathini <hbathini@linux.ibm.com>
> Cc: Nathan Lynch <nathanl@linux.ibm.com>
> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
> Cc: Laurent Dufour <ldufour@linux.ibm.com>
> To: linuxppc-dev@lists.ozlabs.org
> Cc: kexec@lists.infradead.org
> ---
> v4 -> v5: fix the miss of clearing DRCONF_MEM_ASSIGNED in a failure path
> arch/powerpc/platforms/pseries/hotplug-memory.c | 28 +++++++++++++++++--------
> 1 file changed, 19 insertions(+), 9 deletions(-)
>
> diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c
> index 5d545b7..46cbcd1 100644
> --- a/arch/powerpc/platforms/pseries/hotplug-memory.c
> +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c
> @@ -355,7 +355,8 @@ static int dlpar_add_lmb(struct drmem_lmb *);
> static int dlpar_remove_lmb(struct drmem_lmb *lmb)
> {
> unsigned long block_sz;
> - int rc;
> + phys_addr_t base_addr;
> + int rc, nid;
>
> if (!lmb_is_removable(lmb))
> return -EINVAL;
> @@ -364,17 +365,19 @@ static int dlpar_remove_lmb(struct drmem_lmb *lmb)
> if (rc)
> return rc;
>
> + base_addr = lmb->base_addr;
> + nid = lmb->nid;
> block_sz = pseries_memory_block_size();
>
> - __remove_memory(lmb->nid, lmb->base_addr, block_sz);
> -
> - /* Update memory regions for memory remove */
> - memblock_remove(lmb->base_addr, block_sz);
> -
> invalidate_lmb_associativity_index(lmb);
> lmb_clear_nid(lmb);
> lmb->flags &= ~DRCONF_MEM_ASSIGNED;
>
> + __remove_memory(nid, base_addr, block_sz);
> +
> + /* Update memory regions for memory remove */
> + memblock_remove(base_addr, block_sz);
> +
> return 0;
> }
>
> @@ -603,22 +606,29 @@ static int dlpar_add_lmb(struct drmem_lmb *lmb)
> }
>
> lmb_set_nid(lmb);
> + lmb->flags |= DRCONF_MEM_ASSIGNED;
> +
> block_sz = memory_block_size_bytes();
>
> /* Add the memory */
> rc = __add_memory(lmb->nid, lmb->base_addr, block_sz);
> if (rc) {
> invalidate_lmb_associativity_index(lmb);
> + lmb_clear_nid(lmb);
> + lmb->flags &= ~DRCONF_MEM_ASSIGNED;
> return rc;
> }
>
> rc = dlpar_online_lmb(lmb);
> if (rc) {
> - __remove_memory(lmb->nid, lmb->base_addr, block_sz);
> + int nid = lmb->nid;
> + phys_addr_t base_addr = lmb->base_addr;
> +
> invalidate_lmb_associativity_index(lmb);
> lmb_clear_nid(lmb);
> - } else {
> - lmb->flags |= DRCONF_MEM_ASSIGNED;
> + lmb->flags &= ~DRCONF_MEM_ASSIGNED;
> +
> + __remove_memory(nid, base_addr, block_sz);
> }
>
> return rc;
>
^ permalink raw reply
* Re: kernel since 5.6 do not boot anymore on Apple PowerBook
From: Giuseppe Sacco @ 2020-08-27 8:28 UTC (permalink / raw)
To: linuxppc-dev, Christophe Leroy
In-Reply-To: <afd75c134e2c4a57f8cf1f064595455e67b17e41.camel@sguazz.it>
Il giorno gio, 27/08/2020 alle 09.46 +0200, Giuseppe Sacco ha scritto:
> Il giorno gio, 27/08/2020 alle 00.28 +0200, Giuseppe Sacco ha scritto:
> > Hello Christophe,
> >
> > Il giorno mer, 26/08/2020 alle 15.53 +0200, Christophe Leroy ha
> > scritto:
> > [...]
> > > If there is no warning, then the issue is something else, bad luck.
> > >
> > > Could you increase the loglevel and try again both with and without
> > > VMAP_STACK ? Maybe we'll get more information on where it stops.
> >
> > The problem is related to the CPU frequency changes. This is where the
> > system stop: cpufreq get the CPU frequency limits and then start the
> > default governor (performance) and then calls function
> > cpufreq_gov_performance_limits() that never returns.
> >
> > Rebuilding after enabling pr_debug for cpufreq.c, I've got some more
> > lines of output:
> >
> > cpufreq: setting new policy for CPU 0: 667000 - 867000 kHz
> > cpufreq: new min and max freqs are 667000 - 867000 kHz
> > cpufreq: governor switch
> > cpufreq: cpufreq_init_governor: for CPU 0
> > cpufreq: cpufreq_start_governor: for CPU 0
> > cpufreq: target for CPU 0: 867000 kHz, relation 1, requested 867000 kHz
> > cpufreq: __target_index: cpu: 0, oldfreq: 667000, new freq: 867000
> > cpufreq: notification 0 of frequency transition to 867000 kHz
> > cpufreq: saving 133328 as reference value for loops_per_jiffy; freq is 667000 kHz
> >
> > no more lines are printed. I think this output only refers to the
> > notification sent prior to the frequency change.
> >
> > I was thinking that selecting a governor that would run at 667mHz would
> > probably skip the problem. I added cpufreq.default_governor=powersave
> > to the command line parameters but it did not work: the selected
> > governor was still performance and the system crashed.
>
> I kept following the thread and found that CPU frequency is changed in
> function pmu_set_cpu_speed() in file drivers/cpufreq/pmac32-cpufreq.c.
> As first thing, the function calls the macro preempt_disable() and this
> is where it stops.
Sorry, I made a mistake. The real problem is down, on the same
function, when it calls low_sleep_handler(). This is where the problem
probably is.
Bye,
Giuseppe
^ permalink raw reply
* Re: kernel since 5.6 do not boot anymore on Apple PowerBook
From: Giuseppe Sacco @ 2020-08-27 7:46 UTC (permalink / raw)
To: linuxppc-dev, Christophe Leroy
In-Reply-To: <0a18fc199cef2643bd07591205a6234c2edf6c95.camel@sguazz.it>
Il giorno gio, 27/08/2020 alle 00.28 +0200, Giuseppe Sacco ha scritto:
> Hello Christophe,
>
> Il giorno mer, 26/08/2020 alle 15.53 +0200, Christophe Leroy ha
> scritto:
> [...]
> > If there is no warning, then the issue is something else, bad luck.
> >
> > Could you increase the loglevel and try again both with and without
> > VMAP_STACK ? Maybe we'll get more information on where it stops.
>
> The problem is related to the CPU frequency changes. This is where the
> system stop: cpufreq get the CPU frequency limits and then start the
> default governor (performance) and then calls function
> cpufreq_gov_performance_limits() that never returns.
>
> Rebuilding after enabling pr_debug for cpufreq.c, I've got some more
> lines of output:
>
> cpufreq: setting new policy for CPU 0: 667000 - 867000 kHz
> cpufreq: new min and max freqs are 667000 - 867000 kHz
> cpufreq: governor switch
> cpufreq: cpufreq_init_governor: for CPU 0
> cpufreq: cpufreq_start_governor: for CPU 0
> cpufreq: target for CPU 0: 867000 kHz, relation 1, requested 867000 kHz
> cpufreq: __target_index: cpu: 0, oldfreq: 667000, new freq: 867000
> cpufreq: notification 0 of frequency transition to 867000 kHz
> cpufreq: saving 133328 as reference value for loops_per_jiffy; freq is 667000 kHz
>
> no more lines are printed. I think this output only refers to the
> notification sent prior to the frequency change.
>
> I was thinking that selecting a governor that would run at 667mHz would
> probably skip the problem. I added cpufreq.default_governor=powersave
> to the command line parameters but it did not work: the selected
> governor was still performance and the system crashed.
I kept following the thread and found that CPU frequency is changed in
function pmu_set_cpu_speed() in file drivers/cpufreq/pmac32-cpufreq.c.
As first thing, the function calls the macro preempt_disable() and this
is where it stops.
Bye,
Giuseppe
^ permalink raw reply
* [PATCH v3 13/13] mm/debug_vm_pgtable: populate a pte entry before fetching it
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com>
pte_clear_tests operate on an existing pte entry. Make sure that is not a none
pte entry.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
mm/debug_vm_pgtable.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 21329c7d672f..8527ebb75f2c 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -546,7 +546,7 @@ static void __init pgd_populate_tests(struct mm_struct *mm, pgd_t *pgdp,
static void __init pte_clear_tests(struct mm_struct *mm, pte_t *ptep,
unsigned long vaddr)
{
- pte_t pte = ptep_get(ptep);
+ pte_t pte = ptep_get_and_clear(mm, vaddr, ptep);
pr_debug("Validating PTE clear\n");
pte = __pte(pte_val(pte) | RANDOM_ORVALUE);
@@ -944,7 +944,7 @@ static int __init debug_vm_pgtable(void)
p4d_t *p4dp, *saved_p4dp;
pud_t *pudp, *saved_pudp;
pmd_t *pmdp, *saved_pmdp, pmd;
- pte_t *ptep;
+ pte_t *ptep, pte;
pgtable_t saved_ptep;
pgprot_t prot, protnone;
phys_addr_t paddr;
@@ -1049,6 +1049,8 @@ static int __init debug_vm_pgtable(void)
*/
ptep = pte_alloc_map_lock(mm, pmdp, vaddr, &ptl);
+ pte = pfn_pte(pte_aligned, prot);
+ set_pte_at(mm, vaddr, ptep, pte);
pte_clear_tests(mm, ptep, vaddr);
pte_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
pte_unmap_unlock(ptep, ptl);
--
2.26.2
^ permalink raw reply related
* [PATCH v3 12/13] mm/debug_vm_pgtable/hugetlb: Disable hugetlb test on ppc64
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com>
The seems to be missing quite a lot of details w.r.t allocating
the correct pgtable_t page (huge_pte_alloc()), holding the right
lock (huge_pte_lock()) etc. The vma used is also not a hugetlb VMA.
ppc64 do have runtime checks within CONFIG_DEBUG_VM for most of these.
Hence disable the test on ppc64.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
mm/debug_vm_pgtable.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index a188b6e4e37e..21329c7d672f 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -813,6 +813,7 @@ static void __init hugetlb_basic_tests(unsigned long pfn, pgprot_t prot)
#endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */
}
+#ifndef CONFIG_PPC_BOOK3S_64
static void __init hugetlb_advanced_tests(struct mm_struct *mm,
struct vm_area_struct *vma,
pte_t *ptep, unsigned long pfn,
@@ -855,6 +856,7 @@ static void __init hugetlb_advanced_tests(struct mm_struct *mm,
pte = huge_ptep_get(ptep);
WARN_ON(!(huge_pte_write(pte) && huge_pte_dirty(pte)));
}
+#endif
#else /* !CONFIG_HUGETLB_PAGE */
static void __init hugetlb_basic_tests(unsigned long pfn, pgprot_t prot) { }
static void __init hugetlb_advanced_tests(struct mm_struct *mm,
@@ -1065,7 +1067,9 @@ static int __init debug_vm_pgtable(void)
pud_populate_tests(mm, pudp, saved_pmdp);
spin_unlock(ptl);
+#ifndef CONFIG_PPC_BOOK3S_64
hugetlb_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
+#endif
spin_lock(&mm->page_table_lock);
p4d_clear_tests(mm, p4dp);
--
2.26.2
^ permalink raw reply related
* [PATCH v3 11/13] mm/debug_vm_pgtable/pmd_clear: Don't use pmd/pud_clear on pte entries
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com>
pmd_clear() should not be used to clear pmd level pte entries.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
mm/debug_vm_pgtable.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 0a6e771ebd13..a188b6e4e37e 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -196,6 +196,8 @@ static void __init pmd_advanced_tests(struct mm_struct *mm,
pmd = READ_ONCE(*pmdp);
WARN_ON(pmd_young(pmd));
+ /* Clear the pte entries */
+ pmdp_huge_get_and_clear(mm, vaddr, pmdp);
pgtable = pgtable_trans_huge_withdraw(mm, pmdp);
}
@@ -321,6 +323,8 @@ static void __init pud_advanced_tests(struct mm_struct *mm,
pudp_test_and_clear_young(vma, vaddr, pudp);
pud = READ_ONCE(*pudp);
WARN_ON(pud_young(pud));
+
+ pudp_huge_get_and_clear(mm, vaddr, pudp);
}
static void __init pud_leaf_tests(unsigned long pfn, pgprot_t prot)
@@ -444,8 +448,6 @@ static void __init pud_populate_tests(struct mm_struct *mm, pud_t *pudp,
* This entry points to next level page table page.
* Hence this must not qualify as pud_bad().
*/
- pmd_clear(pmdp);
- pud_clear(pudp);
pud_populate(mm, pudp, pmdp);
pud = READ_ONCE(*pudp);
WARN_ON(pud_bad(pud));
@@ -577,7 +579,6 @@ static void __init pmd_populate_tests(struct mm_struct *mm, pmd_t *pmdp,
* This entry points to next level page table page.
* Hence this must not qualify as pmd_bad().
*/
- pmd_clear(pmdp);
pmd_populate(mm, pmdp, pgtable);
pmd = READ_ONCE(*pmdp);
WARN_ON(pmd_bad(pmd));
--
2.26.2
^ permalink raw reply related
* [PATCH v3 09/13] mm/debug_vm_pgtable/locks: Move non page table modifying test together
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com>
This will help in adding proper locks in a later patch
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
mm/debug_vm_pgtable.c | 52 ++++++++++++++++++++++++-------------------
1 file changed, 29 insertions(+), 23 deletions(-)
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 0ce5c6a24c5b..78c8af3445ac 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -992,7 +992,7 @@ static int __init debug_vm_pgtable(void)
p4dp = p4d_alloc(mm, pgdp, vaddr);
pudp = pud_alloc(mm, p4dp, vaddr);
pmdp = pmd_alloc(mm, pudp, vaddr);
- ptep = pte_alloc_map_lock(mm, pmdp, vaddr, &ptl);
+ ptep = pte_alloc_map(mm, pmdp, vaddr);
/*
* Save all the page table page addresses as the page table
@@ -1012,33 +1012,12 @@ static int __init debug_vm_pgtable(void)
p4d_basic_tests(p4d_aligned, prot);
pgd_basic_tests(pgd_aligned, prot);
- pte_clear_tests(mm, ptep, vaddr);
- pmd_clear_tests(mm, pmdp);
- pud_clear_tests(mm, pudp);
- p4d_clear_tests(mm, p4dp);
- pgd_clear_tests(mm, pgdp);
-
- pte_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
- pmd_advanced_tests(mm, vma, pmdp, pmd_aligned, vaddr, prot, saved_ptep);
- pud_advanced_tests(mm, vma, pudp, pud_aligned, vaddr, prot);
- hugetlb_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
-
pmd_leaf_tests(pmd_aligned, prot);
pud_leaf_tests(pud_aligned, prot);
- pmd_huge_tests(pmdp, pmd_aligned, prot);
- pud_huge_tests(pudp, pud_aligned, prot);
-
pte_savedwrite_tests(pte_aligned, protnone);
pmd_savedwrite_tests(pmd_aligned, protnone);
- pte_unmap_unlock(ptep, ptl);
-
- pmd_populate_tests(mm, pmdp, saved_ptep);
- pud_populate_tests(mm, pudp, saved_pmdp);
- p4d_populate_tests(mm, p4dp, saved_pudp);
- pgd_populate_tests(mm, pgdp, saved_p4dp);
-
pte_special_tests(pte_aligned, prot);
pte_protnone_tests(pte_aligned, protnone);
pmd_protnone_tests(pmd_aligned, protnone);
@@ -1056,11 +1035,38 @@ static int __init debug_vm_pgtable(void)
pmd_swap_tests(pmd_aligned, prot);
swap_migration_tests();
- hugetlb_basic_tests(pte_aligned, prot);
pmd_thp_tests(pmd_aligned, prot);
pud_thp_tests(pud_aligned, prot);
+ /*
+ * Page table modifying tests
+ */
+ pte_clear_tests(mm, ptep, vaddr);
+ pmd_clear_tests(mm, pmdp);
+ pud_clear_tests(mm, pudp);
+ p4d_clear_tests(mm, p4dp);
+ pgd_clear_tests(mm, pgdp);
+
+ ptep = pte_alloc_map_lock(mm, pmdp, vaddr, &ptl);
+ pte_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
+ pmd_advanced_tests(mm, vma, pmdp, pmd_aligned, vaddr, prot, saved_ptep);
+ pud_advanced_tests(mm, vma, pudp, pud_aligned, vaddr, prot);
+ hugetlb_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
+
+
+ pmd_huge_tests(pmdp, pmd_aligned, prot);
+ pud_huge_tests(pudp, pud_aligned, prot);
+
+ pte_unmap_unlock(ptep, ptl);
+
+ pmd_populate_tests(mm, pmdp, saved_ptep);
+ pud_populate_tests(mm, pudp, saved_pmdp);
+ p4d_populate_tests(mm, p4dp, saved_pudp);
+ pgd_populate_tests(mm, pgdp, saved_p4dp);
+
+ hugetlb_basic_tests(pte_aligned, prot);
+
p4d_free(mm, saved_p4dp);
pud_free(mm, saved_pudp);
pmd_free(mm, saved_pmdp);
--
2.26.2
^ permalink raw reply related
* [PATCH v3 10/13] mm/debug_vm_pgtable/locks: Take correct page table lock
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com>
Make sure we call pte accessors with correct lock held.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
mm/debug_vm_pgtable.c | 34 ++++++++++++++++++++--------------
1 file changed, 20 insertions(+), 14 deletions(-)
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 78c8af3445ac..0a6e771ebd13 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -1039,33 +1039,39 @@ static int __init debug_vm_pgtable(void)
pmd_thp_tests(pmd_aligned, prot);
pud_thp_tests(pud_aligned, prot);
+ hugetlb_basic_tests(pte_aligned, prot);
+
/*
* Page table modifying tests
*/
- pte_clear_tests(mm, ptep, vaddr);
- pmd_clear_tests(mm, pmdp);
- pud_clear_tests(mm, pudp);
- p4d_clear_tests(mm, p4dp);
- pgd_clear_tests(mm, pgdp);
ptep = pte_alloc_map_lock(mm, pmdp, vaddr, &ptl);
+ pte_clear_tests(mm, ptep, vaddr);
pte_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
- pmd_advanced_tests(mm, vma, pmdp, pmd_aligned, vaddr, prot, saved_ptep);
- pud_advanced_tests(mm, vma, pudp, pud_aligned, vaddr, prot);
- hugetlb_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
-
+ pte_unmap_unlock(ptep, ptl);
+ ptl = pmd_lock(mm, pmdp);
+ pmd_clear_tests(mm, pmdp);
+ pmd_advanced_tests(mm, vma, pmdp, pmd_aligned, vaddr, prot, saved_ptep);
pmd_huge_tests(pmdp, pmd_aligned, prot);
+ pmd_populate_tests(mm, pmdp, saved_ptep);
+ spin_unlock(ptl);
+
+ ptl = pud_lock(mm, pudp);
+ pud_clear_tests(mm, pudp);
+ pud_advanced_tests(mm, vma, pudp, pud_aligned, vaddr, prot);
pud_huge_tests(pudp, pud_aligned, prot);
+ pud_populate_tests(mm, pudp, saved_pmdp);
+ spin_unlock(ptl);
- pte_unmap_unlock(ptep, ptl);
+ hugetlb_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
- pmd_populate_tests(mm, pmdp, saved_ptep);
- pud_populate_tests(mm, pudp, saved_pmdp);
+ spin_lock(&mm->page_table_lock);
+ p4d_clear_tests(mm, p4dp);
+ pgd_clear_tests(mm, pgdp);
p4d_populate_tests(mm, p4dp, saved_pudp);
pgd_populate_tests(mm, pgdp, saved_p4dp);
-
- hugetlb_basic_tests(pte_aligned, prot);
+ spin_unlock(&mm->page_table_lock);
p4d_free(mm, saved_p4dp);
pud_free(mm, saved_pudp);
--
2.26.2
^ permalink raw reply related
* [PATCH v3 08/13] mm/debug_vm_pgtable/thp: Use page table depost/withdraw with THP
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com>
Architectures like ppc64 use deposited page table while updating the huge pte
entries.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
mm/debug_vm_pgtable.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index f9f6358899a8..0ce5c6a24c5b 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -154,7 +154,7 @@ static void __init pmd_basic_tests(unsigned long pfn, pgprot_t prot)
static void __init pmd_advanced_tests(struct mm_struct *mm,
struct vm_area_struct *vma, pmd_t *pmdp,
unsigned long pfn, unsigned long vaddr,
- pgprot_t prot)
+ pgprot_t prot, pgtable_t pgtable)
{
pmd_t pmd;
@@ -165,6 +165,8 @@ static void __init pmd_advanced_tests(struct mm_struct *mm,
/* Align the address wrt HPAGE_PMD_SIZE */
vaddr = (vaddr & HPAGE_PMD_MASK) + HPAGE_PMD_SIZE;
+ pgtable_trans_huge_deposit(mm, pmdp, pgtable);
+
pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
set_pmd_at(mm, vaddr, pmdp, pmd);
pmdp_set_wrprotect(mm, vaddr, pmdp);
@@ -193,6 +195,8 @@ static void __init pmd_advanced_tests(struct mm_struct *mm,
pmdp_test_and_clear_young(vma, vaddr, pmdp);
pmd = READ_ONCE(*pmdp);
WARN_ON(pmd_young(pmd));
+
+ pgtable = pgtable_trans_huge_withdraw(mm, pmdp);
}
static void __init pmd_leaf_tests(unsigned long pfn, pgprot_t prot)
@@ -373,7 +377,7 @@ static void __init pud_basic_tests(unsigned long pfn, pgprot_t prot) { }
static void __init pmd_advanced_tests(struct mm_struct *mm,
struct vm_area_struct *vma, pmd_t *pmdp,
unsigned long pfn, unsigned long vaddr,
- pgprot_t prot)
+ pgprot_t prot, pgtable_t pgtable)
{
}
static void __init pud_advanced_tests(struct mm_struct *mm,
@@ -1015,7 +1019,7 @@ static int __init debug_vm_pgtable(void)
pgd_clear_tests(mm, pgdp);
pte_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
- pmd_advanced_tests(mm, vma, pmdp, pmd_aligned, vaddr, prot);
+ pmd_advanced_tests(mm, vma, pmdp, pmd_aligned, vaddr, prot, saved_ptep);
pud_advanced_tests(mm, vma, pudp, pud_aligned, vaddr, prot);
hugetlb_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
--
2.26.2
^ permalink raw reply related
* [PATCH v3 07/13] mm/debug_vm_pgtable/set_pte/pmd/pud: Don't use set_*_at to update an existing pte entry
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com>
set_pte_at() should not be used to set a pte entry at locations that
already holds a valid pte entry. Architectures like ppc64 don't do TLB
invalidate in set_pte_at() and hence expect it to be used to set locations
that are not a valid PTE.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
mm/debug_vm_pgtable.c | 35 +++++++++++++++--------------------
1 file changed, 15 insertions(+), 20 deletions(-)
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index de83a20c1b30..f9f6358899a8 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -79,15 +79,18 @@ static void __init pte_advanced_tests(struct mm_struct *mm,
{
pte_t pte = pfn_pte(pfn, prot);
+ /*
+ * Architectures optimize set_pte_at by avoiding TLB flush.
+ * This requires set_pte_at to be not used to update an
+ * existing pte entry. Clear pte before we do set_pte_at
+ */
+
pr_debug("Validating PTE advanced\n");
pte = pfn_pte(pfn, prot);
set_pte_at(mm, vaddr, ptep, pte);
ptep_set_wrprotect(mm, vaddr, ptep);
pte = ptep_get(ptep);
WARN_ON(pte_write(pte));
-
- pte = pfn_pte(pfn, prot);
- set_pte_at(mm, vaddr, ptep, pte);
ptep_get_and_clear(mm, vaddr, ptep);
pte = ptep_get(ptep);
WARN_ON(!pte_none(pte));
@@ -101,13 +104,11 @@ static void __init pte_advanced_tests(struct mm_struct *mm,
ptep_set_access_flags(vma, vaddr, ptep, pte, 1);
pte = ptep_get(ptep);
WARN_ON(!(pte_write(pte) && pte_dirty(pte)));
-
- pte = pfn_pte(pfn, prot);
- set_pte_at(mm, vaddr, ptep, pte);
ptep_get_and_clear_full(mm, vaddr, ptep, 1);
pte = ptep_get(ptep);
WARN_ON(!pte_none(pte));
+ pte = pfn_pte(pfn, prot);
pte = pte_mkyoung(pte);
set_pte_at(mm, vaddr, ptep, pte);
ptep_test_and_clear_young(vma, vaddr, ptep);
@@ -169,9 +170,6 @@ static void __init pmd_advanced_tests(struct mm_struct *mm,
pmdp_set_wrprotect(mm, vaddr, pmdp);
pmd = READ_ONCE(*pmdp);
WARN_ON(pmd_write(pmd));
-
- pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
- set_pmd_at(mm, vaddr, pmdp, pmd);
pmdp_huge_get_and_clear(mm, vaddr, pmdp);
pmd = READ_ONCE(*pmdp);
WARN_ON(!pmd_none(pmd));
@@ -185,13 +183,11 @@ static void __init pmd_advanced_tests(struct mm_struct *mm,
pmdp_set_access_flags(vma, vaddr, pmdp, pmd, 1);
pmd = READ_ONCE(*pmdp);
WARN_ON(!(pmd_write(pmd) && pmd_dirty(pmd)));
-
- pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
- set_pmd_at(mm, vaddr, pmdp, pmd);
pmdp_huge_get_and_clear_full(vma, vaddr, pmdp, 1);
pmd = READ_ONCE(*pmdp);
WARN_ON(!pmd_none(pmd));
+ pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
pmd = pmd_mkyoung(pmd);
set_pmd_at(mm, vaddr, pmdp, pmd);
pmdp_test_and_clear_young(vma, vaddr, pmdp);
@@ -293,18 +289,10 @@ static void __init pud_advanced_tests(struct mm_struct *mm,
WARN_ON(pud_write(pud));
#ifndef __PAGETABLE_PMD_FOLDED
-
- pud = pud_mkhuge(pfn_pud(pfn, prot));
- set_pud_at(mm, vaddr, pudp, pud);
pudp_huge_get_and_clear(mm, vaddr, pudp);
pud = READ_ONCE(*pudp);
WARN_ON(!pud_none(pud));
- pud = pud_mkhuge(pfn_pud(pfn, prot));
- set_pud_at(mm, vaddr, pudp, pud);
- pudp_huge_get_and_clear_full(mm, vaddr, pudp, 1);
- pud = READ_ONCE(*pudp);
- WARN_ON(!pud_none(pud));
#endif /* __PAGETABLE_PMD_FOLDED */
pud = pud_mkhuge(pfn_pud(pfn, prot));
@@ -317,6 +305,13 @@ static void __init pud_advanced_tests(struct mm_struct *mm,
pud = READ_ONCE(*pudp);
WARN_ON(!(pud_write(pud) && pud_dirty(pud)));
+#ifndef __PAGETABLE_PMD_FOLDED
+ pudp_huge_get_and_clear_full(mm, vaddr, pudp, 1);
+ pud = READ_ONCE(*pudp);
+ WARN_ON(!pud_none(pud));
+#endif /* __PAGETABLE_PMD_FOLDED */
+
+ pud = pud_mkhuge(pfn_pud(pfn, prot));
pud = pud_mkyoung(pud);
set_pud_at(mm, vaddr, pudp, pud);
pudp_test_and_clear_young(vma, vaddr, pudp);
--
2.26.2
^ permalink raw reply related
* [PATCH v3 06/13] mm/debug_vm_pgtable/THP: Mark the pte entry huge before using set_pmd/pud_at
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com>
kernel expects entries to be marked huge before we use set_pmd_at()/set_pud_at().
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
mm/debug_vm_pgtable.c | 21 ++++++++++++---------
1 file changed, 12 insertions(+), 9 deletions(-)
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 5c0680836fe9..de83a20c1b30 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -155,7 +155,7 @@ static void __init pmd_advanced_tests(struct mm_struct *mm,
unsigned long pfn, unsigned long vaddr,
pgprot_t prot)
{
- pmd_t pmd = pfn_pmd(pfn, prot);
+ pmd_t pmd;
if (!has_transparent_hugepage())
return;
@@ -164,19 +164,19 @@ static void __init pmd_advanced_tests(struct mm_struct *mm,
/* Align the address wrt HPAGE_PMD_SIZE */
vaddr = (vaddr & HPAGE_PMD_MASK) + HPAGE_PMD_SIZE;
- pmd = pfn_pmd(pfn, prot);
+ pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
set_pmd_at(mm, vaddr, pmdp, pmd);
pmdp_set_wrprotect(mm, vaddr, pmdp);
pmd = READ_ONCE(*pmdp);
WARN_ON(pmd_write(pmd));
- pmd = pfn_pmd(pfn, prot);
+ pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
set_pmd_at(mm, vaddr, pmdp, pmd);
pmdp_huge_get_and_clear(mm, vaddr, pmdp);
pmd = READ_ONCE(*pmdp);
WARN_ON(!pmd_none(pmd));
- pmd = pfn_pmd(pfn, prot);
+ pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
pmd = pmd_wrprotect(pmd);
pmd = pmd_mkclean(pmd);
set_pmd_at(mm, vaddr, pmdp, pmd);
@@ -237,7 +237,7 @@ static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot)
static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot)
{
- pmd_t pmd = pfn_pmd(pfn, prot);
+ pmd_t pmd = pmd_mkhuge(pfn_pmd(pfn, prot));
if (!IS_ENABLED(CONFIG_NUMA_BALANCING))
return;
@@ -277,7 +277,7 @@ static void __init pud_advanced_tests(struct mm_struct *mm,
unsigned long pfn, unsigned long vaddr,
pgprot_t prot)
{
- pud_t pud = pfn_pud(pfn, prot);
+ pud_t pud;
if (!has_transparent_hugepage())
return;
@@ -286,25 +286,28 @@ static void __init pud_advanced_tests(struct mm_struct *mm,
/* Align the address wrt HPAGE_PUD_SIZE */
vaddr = (vaddr & HPAGE_PUD_MASK) + HPAGE_PUD_SIZE;
+ pud = pud_mkhuge(pfn_pud(pfn, prot));
set_pud_at(mm, vaddr, pudp, pud);
pudp_set_wrprotect(mm, vaddr, pudp);
pud = READ_ONCE(*pudp);
WARN_ON(pud_write(pud));
#ifndef __PAGETABLE_PMD_FOLDED
- pud = pfn_pud(pfn, prot);
+
+ pud = pud_mkhuge(pfn_pud(pfn, prot));
set_pud_at(mm, vaddr, pudp, pud);
pudp_huge_get_and_clear(mm, vaddr, pudp);
pud = READ_ONCE(*pudp);
WARN_ON(!pud_none(pud));
- pud = pfn_pud(pfn, prot);
+ pud = pud_mkhuge(pfn_pud(pfn, prot));
set_pud_at(mm, vaddr, pudp, pud);
pudp_huge_get_and_clear_full(mm, vaddr, pudp, 1);
pud = READ_ONCE(*pudp);
WARN_ON(!pud_none(pud));
#endif /* __PAGETABLE_PMD_FOLDED */
- pud = pfn_pud(pfn, prot);
+
+ pud = pud_mkhuge(pfn_pud(pfn, prot));
pud = pud_wrprotect(pud);
pud = pud_mkclean(pud);
set_pud_at(mm, vaddr, pudp, pud);
--
2.26.2
^ permalink raw reply related
* [PATCH v3 05/13] mm/debug_vm_pgtable/savedwrite: Enable savedwrite test with CONFIG_NUMA_BALANCING
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com>
Saved write support was added to track the write bit of a pte after marking the
pte protnone. This was done so that AUTONUMA can convert a write pte to protnone
and still track the old write bit. When converting it back we set the pte write
bit correctly thereby avoiding a write fault again. Hence enable the test only
when CONFIG_NUMA_BALANCING is enabled and use protnone protflags.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
mm/debug_vm_pgtable.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 28f9d0558c20..5c0680836fe9 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -119,10 +119,14 @@ static void __init pte_savedwrite_tests(unsigned long pfn, pgprot_t prot)
{
pte_t pte = pfn_pte(pfn, prot);
+ if (!IS_ENABLED(CONFIG_NUMA_BALANCING))
+ return;
+
pr_debug("Validating PTE saved write\n");
WARN_ON(!pte_savedwrite(pte_mk_savedwrite(pte_clear_savedwrite(pte))));
WARN_ON(pte_savedwrite(pte_clear_savedwrite(pte_mk_savedwrite(pte))));
}
+
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
static void __init pmd_basic_tests(unsigned long pfn, pgprot_t prot)
{
@@ -235,6 +239,9 @@ static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot)
{
pmd_t pmd = pfn_pmd(pfn, prot);
+ if (!IS_ENABLED(CONFIG_NUMA_BALANCING))
+ return;
+
pr_debug("Validating PMD saved write\n");
WARN_ON(!pmd_savedwrite(pmd_mk_savedwrite(pmd_clear_savedwrite(pmd))));
WARN_ON(pmd_savedwrite(pmd_clear_savedwrite(pmd_mk_savedwrite(pmd))));
@@ -1020,8 +1027,8 @@ static int __init debug_vm_pgtable(void)
pmd_huge_tests(pmdp, pmd_aligned, prot);
pud_huge_tests(pudp, pud_aligned, prot);
- pte_savedwrite_tests(pte_aligned, prot);
- pmd_savedwrite_tests(pmd_aligned, prot);
+ pte_savedwrite_tests(pte_aligned, protnone);
+ pmd_savedwrite_tests(pmd_aligned, protnone);
pte_unmap_unlock(ptep, ptl);
--
2.26.2
^ permalink raw reply related
* [PATCH v3 04/13] mm/debug_vm_pgtables/hugevmap: Use the arch helper to identify huge vmap support.
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com>
ppc64 supports huge vmap only with radix translation. Hence use arch helper
to determine the huge vmap support.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
mm/debug_vm_pgtable.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index bbf9df0e64c6..28f9d0558c20 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -28,6 +28,7 @@
#include <linux/swapops.h>
#include <linux/start_kernel.h>
#include <linux/sched/mm.h>
+#include <linux/io.h>
#include <asm/pgalloc.h>
#include <asm/tlbflush.h>
@@ -206,11 +207,12 @@ static void __init pmd_leaf_tests(unsigned long pfn, pgprot_t prot)
WARN_ON(!pmd_leaf(pmd));
}
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot)
{
pmd_t pmd;
- if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMAP))
+ if (!arch_ioremap_pmd_supported())
return;
pr_debug("Validating PMD huge\n");
@@ -224,6 +226,10 @@ static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot)
pmd = READ_ONCE(*pmdp);
WARN_ON(!pmd_none(pmd));
}
+#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
+static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot) { }
+#endif /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
+
static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot)
{
@@ -320,11 +326,12 @@ static void __init pud_leaf_tests(unsigned long pfn, pgprot_t prot)
WARN_ON(!pud_leaf(pud));
}
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
static void __init pud_huge_tests(pud_t *pudp, unsigned long pfn, pgprot_t prot)
{
pud_t pud;
- if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMAP))
+ if (!arch_ioremap_pud_supported())
return;
pr_debug("Validating PUD huge\n");
@@ -338,6 +345,10 @@ static void __init pud_huge_tests(pud_t *pudp, unsigned long pfn, pgprot_t prot)
pud = READ_ONCE(*pudp);
WARN_ON(!pud_none(pud));
}
+#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
+static void __init pud_huge_tests(pud_t *pudp, unsigned long pfn, pgprot_t prot) { }
+#endif /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
+
#else /* !CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
static void __init pud_basic_tests(unsigned long pfn, pgprot_t prot) { }
static void __init pud_advanced_tests(struct mm_struct *mm,
--
2.26.2
^ permalink raw reply related
* [PATCH v3 03/13] mm/debug_vm_pgtable/ppc64: Avoid setting top bits in radom value
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com>
ppc64 use bit 62 to indicate a pte entry (_PAGE_PTE). Avoid setting that bit in
random value.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
mm/debug_vm_pgtable.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 086309fb9b6f..bbf9df0e64c6 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -44,10 +44,17 @@
* entry type. But these bits might affect the ability to clear entries with
* pxx_clear() because of how dynamic page table folding works on s390. So
* while loading up the entries do not change the lower 4 bits. It does not
- * have affect any other platform.
+ * have affect any other platform. Also avoid the 62nd bit on ppc64 that is
+ * used to mark a pte entry.
*/
-#define S390_MASK_BITS 4
-#define RANDOM_ORVALUE GENMASK(BITS_PER_LONG - 1, S390_MASK_BITS)
+#define S390_SKIP_MASK GENMASK(3, 0)
+#ifdef CONFIG_PPC_BOOK3S_64
+#define PPC64_SKIP_MASK GENMASK(62, 62)
+#else
+#define PPC64_SKIP_MASK 0x0
+#endif
+#define ARCH_SKIP_MASK (S390_SKIP_MASK | PPC64_SKIP_MASK)
+#define RANDOM_ORVALUE (GENMASK(BITS_PER_LONG - 1, 0) & ~ARCH_SKIP_MASK)
#define RANDOM_NZVALUE GENMASK(7, 0)
static void __init pte_basic_tests(unsigned long pfn, pgprot_t prot)
--
2.26.2
^ permalink raw reply related
* [PATCH v3 02/13] powerpc/mm: Move setting pte specific flags to pfn_pte
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com>
powerpc used to set the pte specific flags in set_pte_at(). This is different
from other architectures. To be consistent with other architecture update
pfn_pte to set _PAGE_PTE on ppc64. Also, drop now unused pte_mkpte.
We add a VM_WARN_ON() to catch the usage of calling set_pte_at() without setting
_PAGE_PTE bit. We will remove that after a few releases.
With respect to huge pmd entries, pmd_mkhuge() takes care of adding the
_PAGE_PTE bit.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/pgtable.h | 15 +++++++++------
arch/powerpc/include/asm/nohash/pgtable.h | 5 -----
arch/powerpc/mm/pgtable.c | 5 -----
3 files changed, 9 insertions(+), 16 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index 079211968987..2382fd516f6b 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -619,7 +619,7 @@ static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
VM_BUG_ON(pfn >> (64 - PAGE_SHIFT));
VM_BUG_ON((pfn << PAGE_SHIFT) & ~PTE_RPN_MASK);
- return __pte(((pte_basic_t)pfn << PAGE_SHIFT) | pgprot_val(pgprot));
+ return __pte(((pte_basic_t)pfn << PAGE_SHIFT) | pgprot_val(pgprot) | _PAGE_PTE);
}
static inline unsigned long pte_pfn(pte_t pte)
@@ -655,11 +655,6 @@ static inline pte_t pte_mkexec(pte_t pte)
return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_EXEC));
}
-static inline pte_t pte_mkpte(pte_t pte)
-{
- return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_PTE));
-}
-
static inline pte_t pte_mkwrite(pte_t pte)
{
/*
@@ -823,6 +818,14 @@ static inline int pte_none(pte_t pte)
static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pte, int percpu)
{
+
+ VM_WARN_ON(!(pte_raw(pte) & cpu_to_be64(_PAGE_PTE)));
+ /*
+ * Keep the _PAGE_PTE added till we are sure we handle _PAGE_PTE
+ * in all the callers.
+ */
+ pte = __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_PTE));
+
if (radix_enabled())
return radix__set_pte_at(mm, addr, ptep, pte, percpu);
return hash__set_pte_at(mm, addr, ptep, pte, percpu);
diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h
index 4b7c3472eab1..6277e7596ae5 100644
--- a/arch/powerpc/include/asm/nohash/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/pgtable.h
@@ -140,11 +140,6 @@ static inline pte_t pte_mkold(pte_t pte)
return __pte(pte_val(pte) & ~_PAGE_ACCESSED);
}
-static inline pte_t pte_mkpte(pte_t pte)
-{
- return pte;
-}
-
static inline pte_t pte_mkspecial(pte_t pte)
{
return __pte(pte_val(pte) | _PAGE_SPECIAL);
diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
index 9c0547d77af3..ab57b07ef39a 100644
--- a/arch/powerpc/mm/pgtable.c
+++ b/arch/powerpc/mm/pgtable.c
@@ -184,9 +184,6 @@ void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
*/
VM_WARN_ON(pte_hw_valid(*ptep) && !pte_protnone(*ptep));
- /* Add the pte bit when trying to set a pte */
- pte = pte_mkpte(pte);
-
/* Note: mm->context.id might not yet have been assigned as
* this context might not have been activated yet when this
* is called.
@@ -275,8 +272,6 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_
*/
VM_WARN_ON(pte_hw_valid(*ptep) && !pte_protnone(*ptep));
- pte = pte_mkpte(pte);
-
pte = set_pte_filter(pte);
val = pte_val(pte);
--
2.26.2
^ permalink raw reply related
* [PATCH v3 01/13] powerpc/mm: Add DEBUG_VM WARN for pmd_clear
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
In-Reply-To: <20200827080438.315345-1-aneesh.kumar@linux.ibm.com>
With the hash page table, the kernel should not use pmd_clear for clearing
huge pte entries. Add a DEBUG_VM WARN to catch the wrong usage.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/pgtable.h | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index 6de56c3b33c4..079211968987 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -868,6 +868,13 @@ static inline bool pte_ci(pte_t pte)
static inline void pmd_clear(pmd_t *pmdp)
{
+ if (IS_ENABLED(CONFIG_DEBUG_VM) && !radix_enabled()) {
+ /*
+ * Don't use this if we can possibly have a hash page table
+ * entry mapping this.
+ */
+ WARN_ON((pmd_val(*pmdp) & (H_PAGE_HASHPTE | _PAGE_PTE)) == (H_PAGE_HASHPTE | _PAGE_PTE));
+ }
*pmdp = __pmd(0);
}
@@ -916,6 +923,13 @@ static inline int pmd_bad(pmd_t pmd)
static inline void pud_clear(pud_t *pudp)
{
+ if (IS_ENABLED(CONFIG_DEBUG_VM) && !radix_enabled()) {
+ /*
+ * Don't use this if we can possibly have a hash page table
+ * entry mapping this.
+ */
+ WARN_ON((pud_val(*pudp) & (H_PAGE_HASHPTE | _PAGE_PTE)) == (H_PAGE_HASHPTE | _PAGE_PTE));
+ }
*pudp = __pud(0);
}
--
2.26.2
^ permalink raw reply related
* [PATCH v3 00/13] mm/debug_vm_pgtable fixes
From: Aneesh Kumar K.V @ 2020-08-27 8:04 UTC (permalink / raw)
To: linux-mm, akpm
Cc: linux-arch, linux-s390, Anshuman Khandual, Aneesh Kumar K.V, x86,
Mike Rapoport, Qian Cai, Gerald Schaefer, Christophe Leroy,
Vineet Gupta, linux-snps-arc, linuxppc-dev, linux-arm-kernel
This patch series includes fixes for debug_vm_pgtable test code so that
they follow page table updates rules correctly. The first two patches introduce
changes w.r.t ppc64. The patches are included in this series for completeness. We can
merge them via ppc64 tree if required.
Hugetlb test is disabled on ppc64 because that needs larger change to satisfy
page table update rules.
The patches are on top of 15bc20c6af4ceee97a1f90b43c0e386643c071b4 (linus/master)
Changes from v2:
* Fix build failure with different configs and architecture.
Changes from v1:
* Address review feedback
* drop test specific pfn_pte and pfn_pmd.
* Update ppc64 page table helper to add _PAGE_PTE
Aneesh Kumar K.V (13):
powerpc/mm: Add DEBUG_VM WARN for pmd_clear
powerpc/mm: Move setting pte specific flags to pfn_pte
mm/debug_vm_pgtable/ppc64: Avoid setting top bits in radom value
mm/debug_vm_pgtables/hugevmap: Use the arch helper to identify huge
vmap support.
mm/debug_vm_pgtable/savedwrite: Enable savedwrite test with
CONFIG_NUMA_BALANCING
mm/debug_vm_pgtable/THP: Mark the pte entry huge before using
set_pmd/pud_at
mm/debug_vm_pgtable/set_pte/pmd/pud: Don't use set_*_at to update an
existing pte entry
mm/debug_vm_pgtable/thp: Use page table depost/withdraw with THP
mm/debug_vm_pgtable/locks: Move non page table modifying test together
mm/debug_vm_pgtable/locks: Take correct page table lock
mm/debug_vm_pgtable/pmd_clear: Don't use pmd/pud_clear on pte entries
mm/debug_vm_pgtable/hugetlb: Disable hugetlb test on ppc64
mm/debug_vm_pgtable: populate a pte entry before fetching it
arch/powerpc/include/asm/book3s/64/pgtable.h | 29 +++-
arch/powerpc/include/asm/nohash/pgtable.h | 5 -
arch/powerpc/mm/pgtable.c | 5 -
mm/debug_vm_pgtable.c | 170 ++++++++++++-------
4 files changed, 131 insertions(+), 78 deletions(-)
--
2.26.2
^ permalink raw reply
* [PATCH v3 5/6] powerpc: Initialize a temporary mm for code patching
From: Christopher M. Riedl @ 2020-08-27 5:26 UTC (permalink / raw)
To: linuxppc-dev; +Cc: kernel-hardening
In-Reply-To: <20200827052659.24922-1-cmr@codefail.de>
When code patching a STRICT_KERNEL_RWX kernel the page containing the
address to be patched is temporarily mapped with permissive memory
protections. Currently, a per-cpu vmalloc patch area is used for this
purpose. While the patch area is per-cpu, the temporary page mapping is
inserted into the kernel page tables for the duration of the patching.
The mapping is exposed to CPUs other than the patching CPU - this is
undesirable from a hardening perspective.
Use the `poking_init` init hook to prepare a temporary mm and patching
address. Initialize the temporary mm by copying the init mm. Choose a
randomized patching address inside the temporary mm userspace address
portion. The next patch uses the temporary mm and patching address for
code patching.
Based on x86 implementation:
commit 4fc19708b165
("x86/alternatives: Initialize temporary mm for patching")
Signed-off-by: Christopher M. Riedl <cmr@codefail.de>
---
arch/powerpc/lib/code-patching.c | 40 ++++++++++++++++++++++++++++++++
1 file changed, 40 insertions(+)
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index 89b37ece6d2f..051d7ae6d8ee 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -11,6 +11,8 @@
#include <linux/cpuhotplug.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
+#include <linux/sched/task.h>
+#include <linux/random.h>
#include <asm/tlbflush.h>
#include <asm/page.h>
@@ -109,6 +111,44 @@ static inline void unuse_temporary_mm(struct temp_mm *temp_mm)
}
}
+static struct mm_struct *patching_mm __ro_after_init;
+static unsigned long patching_addr __ro_after_init;
+
+void __init poking_init(void)
+{
+ spinlock_t *ptl; /* for protecting pte table */
+ pte_t *ptep;
+
+ /*
+ * Some parts of the kernel (static keys for example) depend on
+ * successful code patching. Code patching under STRICT_KERNEL_RWX
+ * requires this setup - otherwise we cannot patch at all. We use
+ * BUG_ON() here and later since an early failure is preferred to
+ * buggy behavior and/or strange crashes later.
+ */
+ patching_mm = copy_init_mm();
+ BUG_ON(!patching_mm);
+
+ /*
+ * Choose a randomized, page-aligned address from the range:
+ * [PAGE_SIZE, DEFAULT_MAP_WINDOW - PAGE_SIZE]
+ * The lower address bound is PAGE_SIZE to avoid the zero-page.
+ * The upper address bound is DEFAULT_MAP_WINDOW - PAGE_SIZE to stay
+ * under DEFAULT_MAP_WINDOW in hash.
+ */
+ patching_addr = PAGE_SIZE + ((get_random_long() & PAGE_MASK)
+ % (DEFAULT_MAP_WINDOW - 2 * PAGE_SIZE));
+
+ /*
+ * PTE allocation uses GFP_KERNEL which means we need to pre-allocate
+ * the PTE here. We cannot do the allocation during patching with IRQs
+ * disabled (ie. "atomic" context).
+ */
+ ptep = get_locked_pte(patching_mm, patching_addr, &ptl);
+ BUG_ON(!ptep);
+ pte_unmap_unlock(ptep, ptl);
+}
+
static DEFINE_PER_CPU(struct vm_struct *, text_poke_area);
#ifdef CONFIG_LKDTM
--
2.28.0
^ permalink raw reply related
* Re: [PATCHv5 2/2] powerpc/pseries: update device tree before ejecting hotplug uevents
From: Laurent Dufour @ 2020-08-27 7:53 UTC (permalink / raw)
To: Pingfan Liu, linuxppc-dev
Cc: Nathan Lynch, kexec, Hari Bathini, Nathan Fontenot
In-Reply-To: <1597049570-19536-2-git-send-email-kernelfans@gmail.com>
Le 10/08/2020 à 10:52, Pingfan Liu a écrit :
> A bug is observed on pseries by taking the following steps on rhel:
> -1. drmgr -c mem -r -q 5
> -2. echo c > /proc/sysrq-trigger
>
> And then, the failure looks like:
> kdump: saving to /sysroot//var/crash/127.0.0.1-2020-01-16-02:06:14/
> kdump: saving vmcore-dmesg.txt
> kdump: saving vmcore-dmesg.txt complete
> kdump: saving vmcore
> Checking for memory holes : [ 0.0 %] / Checking for memory holes : [100.0 %] | Excluding unnecessary pages : [100.0 %] \ Copying data : [ 0.3 %] - eta: 38s[ 44.337636] hash-mmu: mm: Hashing failure ! EA=0x7fffba400000 access=0x8000000000000004 current=makedumpfile
> [ 44.337663] hash-mmu: trap=0x300 vsid=0x13a109c ssize=1 base psize=2 psize 2 pte=0xc000000050000504
> [ 44.337677] hash-mmu: mm: Hashing failure ! EA=0x7fffba400000 access=0x8000000000000004 current=makedumpfile
> [ 44.337692] hash-mmu: trap=0x300 vsid=0x13a109c ssize=1 base psize=2 psize 2 pte=0xc000000050000504
> [ 44.337708] makedumpfile[469]: unhandled signal 7 at 00007fffba400000 nip 00007fffbbc4d7fc lr 000000011356ca3c code 2
> [ 44.338548] Core dump to |/bin/false pipe failed
> /lib/kdump-lib-initramfs.sh: line 98: 469 Bus error $CORE_COLLECTOR /proc/vmcore $_mp/$KDUMP_PATH/$HOST_IP-$DATEDIR/vmcore-incomplete
> kdump: saving vmcore failed
>
> * Root cause *
> After analyzing, it turns out that in the current implementation,
> when hot-removing lmb, the KOBJ_REMOVE event ejects before the dt updating as
> the code __remove_memory() comes before drmem_update_dt().
> So in kdump kernel, when read_from_oldmem() resorts to
> pSeries_lpar_hpte_insert() to install hpte, but fails with -2 due to
> non-exist pfn. And finally, low_hash_fault() raise SIGBUS to process, as it
> can be observed "Bus error"
>
> From a viewpoint of listener and publisher, the publisher notifies the
> listener before data is ready. This introduces a problem where udev
> launches kexec-tools (due to KOBJ_REMOVE) and loads a stale dt before
> updating. And in capture kernel, makedumpfile will access the memory based
> on the stale dt info, and hit a SIGBUS error due to an un-existed lmb.
>
> * Fix *
> This bug is introduced by commit 063b8b1251fd
> ("powerpc/pseries/memory-hotplug: Only update DT once per memory DLPAR
> request"), which tried to combine all the dt updating into one.
>
> To fix this issue, meanwhile not to introduce a quadratic runtime
> complexity by the model:
> dlpar_memory_add_by_count
> for_each_drmem_lmb <--
> dlpar_add_lmb
> drmem_update_dt(_v1|_v2)
> for_each_drmem_lmb <--
> The dt should still be only updated once, and just before the last memory
> online/offline event is ejected to user space. Achieve this by tracing the
> num of lmb added or removed.
>
> Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Hari Bathini <hbathini@linux.ibm.com>
> Cc: Nathan Lynch <nathanl@linux.ibm.com>
> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
> Cc: Laurent Dufour <ldufour@linux.ibm.com>
> To: linuxppc-dev@lists.ozlabs.org
> Cc: kexec@lists.infradead.org
> ---
> v4 -> v5: change dlpar_add_lmb()/dlpar_remove_lmb() prototype to report
> whether dt is updated successfully.
> Fix a condition boundary check bug
> v3 -> v4: resolve a quadratic runtime complexity issue.
> This series is applied on next-test branch
> arch/powerpc/platforms/pseries/hotplug-memory.c | 102 +++++++++++++++++++-----
> 1 file changed, 80 insertions(+), 22 deletions(-)
>
> diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c
> index 46cbcd1..1567d9f 100644
> --- a/arch/powerpc/platforms/pseries/hotplug-memory.c
> +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c
> @@ -350,13 +350,22 @@ static bool lmb_is_removable(struct drmem_lmb *lmb)
> return true;
> }
>
> -static int dlpar_add_lmb(struct drmem_lmb *);
> +enum dt_update_status {
> + DT_NOUPDATE,
> + DT_TOUPDATE,
> + DT_UPDATED,
> +};
> +
> +/* "*dt_update" returns DT_UPDATED if updated */
> +static int dlpar_add_lmb(struct drmem_lmb *lmb,
> + enum dt_update_status *dt_update);
>
> -static int dlpar_remove_lmb(struct drmem_lmb *lmb)
> +static int dlpar_remove_lmb(struct drmem_lmb *lmb,
> + enum dt_update_status *dt_update)
> {
> unsigned long block_sz;
> phys_addr_t base_addr;
> - int rc, nid;
> + int rc, ret, nid;
>
> if (!lmb_is_removable(lmb))
> return -EINVAL;
> @@ -372,6 +381,13 @@ static int dlpar_remove_lmb(struct drmem_lmb *lmb)
> invalidate_lmb_associativity_index(lmb);
> lmb_clear_nid(lmb);
> lmb->flags &= ~DRCONF_MEM_ASSIGNED;
> + if (*dt_update) {
That test is wrong, you should do:
if (*dt_update && *dt_update == DT_TOUPDATE) {
With the current code, the device tree is updated all the time.
Another option would be to pass a valid pointer (!= NULL) only when DT update is
required, this way you don't need the DT_TOUPDATE value. The caller would have
to set the pointer accordingly. The advantage with this option is the caller is
guaranteed that its variable is not touched by the callee when no device tree is
requested. A simple boolean pointer would be enough without the need to this enum.
> + ret = drmem_update_dt();
> + if (ret)
> + pr_warn("%s fail to update dt, but continue\n", __func__);
> + else
> + *dt_update = DT_UPDATED;
> + }
>
> __remove_memory(nid, base_addr, block_sz);
>
> @@ -387,6 +403,7 @@ static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
> int lmbs_removed = 0;
> int lmbs_available = 0;
> int rc;
> + enum dt_update_status dt_update = DT_NOUPDATE;
>
> pr_info("Attempting to hot-remove %d LMB(s)\n", lmbs_to_remove);
>
> @@ -409,7 +426,11 @@ static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
> }
>
> for_each_drmem_lmb(lmb) {
> - rc = dlpar_remove_lmb(lmb);
> +
> + /* combine dt updating for all LMBs */
> + if (lmbs_to_remove - lmbs_removed <= 1)
> + dt_update = DT_TOUPDATE;
> + rc = dlpar_remove_lmb(lmb, &dt_update);
> if (rc)
> continue;
>
> @@ -424,13 +445,17 @@ static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
> }
>
> if (lmbs_removed != lmbs_to_remove) {
> + enum dt_update_status rollback_dt_update = DT_NOUPDATE;
> +
> pr_err("Memory hot-remove failed, adding LMB's back\n");
>
> for_each_drmem_lmb(lmb) {
> if (!drmem_lmb_reserved(lmb))
> continue;
>
> - rc = dlpar_add_lmb(lmb);
> + if (--lmbs_removed == 0 && dt_update == DT_UPDATED)
> + rollback_dt_update = DT_TOUPDATE;
> + rc = dlpar_add_lmb(lmb, &rollback_dt_update);
> if (rc)
> pr_err("Failed to add LMB back, drc index %x\n",
> lmb->drc_index);
> @@ -458,6 +483,7 @@ static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
>
> static int dlpar_memory_remove_by_index(u32 drc_index)
> {
> + enum dt_update_status dt_update = DT_TOUPDATE;
> struct drmem_lmb *lmb;
> int lmb_found;
> int rc;
> @@ -468,7 +494,7 @@ static int dlpar_memory_remove_by_index(u32 drc_index)
> for_each_drmem_lmb(lmb) {
> if (lmb->drc_index == drc_index) {
> lmb_found = 1;
> - rc = dlpar_remove_lmb(lmb);
> + rc = dlpar_remove_lmb(lmb, &dt_update);
> if (!rc)
> dlpar_release_drc(lmb->drc_index);
>
> @@ -490,6 +516,7 @@ static int dlpar_memory_remove_by_index(u32 drc_index)
>
> static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
> {
> + enum dt_update_status dt_update = DT_NOUPDATE;
> struct drmem_lmb *lmb, *start_lmb, *end_lmb;
> int lmbs_available = 0;
> int rc;
> @@ -519,7 +546,9 @@ static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
> if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
> continue;
>
> - rc = dlpar_remove_lmb(lmb);
> + if (lmb == end_lmb)
> + dt_update = DT_TOUPDATE;
> + rc = dlpar_remove_lmb(lmb, &dt_update);
> if (rc)
> break;
>
> @@ -527,14 +556,16 @@ static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
> }
>
> if (rc) {
> - pr_err("Memory indexed-count-remove failed, adding any removed LMBs\n");
> + enum dt_update_status rollback_dt_update = DT_NOUPDATE;
>
> + pr_err("Memory indexed-count-remove failed, adding any removed LMBs\n");
>
> for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
> if (!drmem_lmb_reserved(lmb))
> continue;
> -
> - rc = dlpar_add_lmb(lmb);
> + if (lmb == end_lmb && dt_update == DT_UPDATED)
> + rollback_dt_update = DT_TOUPDATE;
> + rc = dlpar_add_lmb(lmb, &rollback_dt_update);
> if (rc)
> pr_err("Failed to add LMB, drc index %x\n",
> lmb->drc_index);
> @@ -572,7 +603,7 @@ static inline int dlpar_memory_remove(struct pseries_hp_errorlog *hp_elog)
> {
> return -EOPNOTSUPP;
> }
> -static int dlpar_remove_lmb(struct drmem_lmb *lmb)
> +static int dlpar_remove_lmb(struct drmem_lmb *lmb, bool dt_update)
> {
> return -EOPNOTSUPP;
> }
> @@ -591,10 +622,11 @@ static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
> }
> #endif /* CONFIG_MEMORY_HOTREMOVE */
>
> -static int dlpar_add_lmb(struct drmem_lmb *lmb)
> +static int dlpar_add_lmb(struct drmem_lmb *lmb,
> + enum dt_update_status *dt_update)
> {
> unsigned long block_sz;
> - int rc;
> + int rc, ret;
>
> if (lmb->flags & DRCONF_MEM_ASSIGNED)
> return -EINVAL;
> @@ -607,6 +639,13 @@ static int dlpar_add_lmb(struct drmem_lmb *lmb)
>
> lmb_set_nid(lmb);
> lmb->flags |= DRCONF_MEM_ASSIGNED;
> + if (*dt_update) {
> + ret = drmem_update_dt();
> + if (ret)
> + pr_warn("%s fail to update dt, but continue\n", __func__);
> + else
> + *dt_update = DT_UPDATED;
> + }
>
> block_sz = memory_block_size_bytes();
>
> @@ -616,6 +655,8 @@ static int dlpar_add_lmb(struct drmem_lmb *lmb)
> invalidate_lmb_associativity_index(lmb);
> lmb_clear_nid(lmb);
> lmb->flags &= ~DRCONF_MEM_ASSIGNED;
> + if (*dt_update == DT_UPDATED)
> + drmem_update_dt();
> return rc;
> }
>
> @@ -627,7 +668,11 @@ static int dlpar_add_lmb(struct drmem_lmb *lmb)
> invalidate_lmb_associativity_index(lmb);
> lmb_clear_nid(lmb);
> lmb->flags &= ~DRCONF_MEM_ASSIGNED;
> -
> + if (*dt_update == DT_UPDATED) {
> + ret = drmem_update_dt();
> + if (ret)
> + pr_warn("%s fail to update dt during rollback, but continue\n", __func__);
> + }
> __remove_memory(nid, base_addr, block_sz);
> }
>
> @@ -636,6 +681,7 @@ static int dlpar_add_lmb(struct drmem_lmb *lmb)
>
> static int dlpar_memory_add_by_count(u32 lmbs_to_add)
> {
> + enum dt_update_status dt_update = DT_NOUPDATE;
> struct drmem_lmb *lmb;
> int lmbs_available = 0;
> int lmbs_added = 0;
> @@ -666,7 +712,9 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add)
> if (rc)
> continue;
>
> - rc = dlpar_add_lmb(lmb);
> + if (lmbs_to_add - lmbs_added <= 1)
> + dt_update = DT_TOUPDATE;
> + rc = dlpar_add_lmb(lmb, &dt_update);
> if (rc) {
> dlpar_release_drc(lmb->drc_index);
> continue;
> @@ -683,13 +731,18 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add)
> }
>
> if (lmbs_added != lmbs_to_add) {
> + enum dt_update_status rollback_dt_update = DT_NOUPDATE;
> +
> pr_err("Memory hot-add failed, removing any added LMBs\n");
>
> for_each_drmem_lmb(lmb) {
> if (!drmem_lmb_reserved(lmb))
> continue;
>
> - rc = dlpar_remove_lmb(lmb);
> + if (--lmbs_added == 0 && dt_update == DT_UPDATED)
> + rollback_dt_update = DT_TOUPDATE;
> +
> + rc = dlpar_remove_lmb(lmb, &rollback_dt_update);
> if (rc)
> pr_err("Failed to remove LMB, drc index %x\n",
> lmb->drc_index);
> @@ -716,6 +769,7 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add)
>
> static int dlpar_memory_add_by_index(u32 drc_index)
> {
> + enum dt_update_status dt_update = DT_TOUPDATE;
> struct drmem_lmb *lmb;
> int rc, lmb_found;
>
> @@ -727,7 +781,7 @@ static int dlpar_memory_add_by_index(u32 drc_index)
> lmb_found = 1;
> rc = dlpar_acquire_drc(lmb->drc_index);
> if (!rc) {
> - rc = dlpar_add_lmb(lmb);
> + rc = dlpar_add_lmb(lmb, &dt_update);
> if (rc)
> dlpar_release_drc(lmb->drc_index);
> }
> @@ -750,6 +804,7 @@ static int dlpar_memory_add_by_index(u32 drc_index)
>
> static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index)
> {
> + enum dt_update_status dt_update = DT_NOUPDATE;
> struct drmem_lmb *lmb, *start_lmb, *end_lmb;
> int lmbs_available = 0;
> int rc;
> @@ -783,7 +838,9 @@ static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index)
> if (rc)
> break;
>
> - rc = dlpar_add_lmb(lmb);
> + if (lmb == end_lmb)
> + dt_update = DT_TOUPDATE;
> + rc = dlpar_add_lmb(lmb, &dt_update);
> if (rc) {
> dlpar_release_drc(lmb->drc_index);
> break;
> @@ -796,10 +853,14 @@ static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index)
> pr_err("Memory indexed-count-add failed, removing any added LMBs\n");
>
> for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
> + enum dt_update_status rollback_dt_update = DT_NOUPDATE;
> +
> if (!drmem_lmb_reserved(lmb))
> continue;
>
> - rc = dlpar_remove_lmb(lmb);
> + if (lmb == end_lmb && dt_update == DT_UPDATED)
> + rollback_dt_update = DT_TOUPDATE;
> + rc = dlpar_remove_lmb(lmb, &rollback_dt_update);
> if (rc)
> pr_err("Failed to remove LMB, drc index %x\n",
> lmb->drc_index);
> @@ -879,9 +940,6 @@ int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
> break;
> }
>
> - if (!rc)
> - rc = drmem_update_dt();
> -
> unlock_device_hotplug();
> return rc;
> }
>
^ permalink raw reply
* Re: [PATCH v2 0/3] Reintroduce PROT_SAO
From: Michael Ellerman @ 2020-08-27 7:46 UTC (permalink / raw)
To: linuxppc-dev, Shawn Anastasio; +Cc: npiggin
In-Reply-To: <20200821185558.35561-1-shawn@anastas.io>
On Fri, 21 Aug 2020 13:55:55 -0500, Shawn Anastasio wrote:
> Changes in v2:
> - Update prot_sao selftest to skip ISA 3.1
>
> This set re-introduces the PROT_SAO prot flag removed in
> Commit 5c9fa16e8abd ("powerpc/64s: Remove PROT_SAO support").
>
> To address concerns regarding live migration of guests using SAO
> to P10 hosts without SAO support, the flag is disabled by default
> in LPARs. A new config option, PPC_PROT_SAO_LPAR was added to
> allow users to explicitly enable it if they will not be running
> in an environment where this is a conern.
>
> [...]
Applied to powerpc/fixes.
[1/3] Revert "powerpc/64s: Remove PROT_SAO support"
https://git.kernel.org/powerpc/c/12564485ed8caac3c18572793ec01330792c7191
[2/3] powerpc/64s: Disallow PROT_SAO in LPARs by default
https://git.kernel.org/powerpc/c/9b725a90a8f127802e19466d4e336e701bcea0d2
[3/3] selftests/powerpc: Update PROT_SAO test to skip ISA 3.1
https://git.kernel.org/powerpc/c/24ded46f53f954b9cf246c5d4e3770c7a8aa84ce
cheers
^ permalink raw reply
* Re: [PATCH] Documentation/powerpc: fix malformed table in syscall64-abi
From: Michael Ellerman @ 2020-08-27 7:46 UTC (permalink / raw)
To: Michael Ellerman, LKML, linux-doc@vger.kernel.org,
Nicholas Piggin, Randy Dunlap, linuxppc-dev
In-Reply-To: <e06de4d3-a36f-2745-9775-467e125436cc@infradead.org>
On Sun, 23 Aug 2020 17:31:16 -0700, Randy Dunlap wrote:
> Fix malformed table warning in powerpc/syscall64-abi.rst by making
> two tables and moving the headings.
>
> Documentation/powerpc/syscall64-abi.rst:53: WARNING: Malformed table.
> Text in column margin in table line 2.
>
> =========== ============= ========================================
> --- For the sc instruction, differences with the ELF ABI ---
> r0 Volatile (System call number.)
> r3 Volatile (Parameter 1, and return value.)
> r4-r8 Volatile (Parameters 2-6.)
> cr0 Volatile (cr0.SO is the return error condition.)
> cr1, cr5-7 Nonvolatile
> lr Nonvolatile
>
> [...]
Applied to powerpc/fixes.
[1/1] Documentation/powerpc: fix malformed table in syscall64-abi
https://git.kernel.org/powerpc/c/aa661d7fab436d8a782618b3138da1a84ca28a31
cheers
^ permalink raw reply
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