From: Christian Borntraeger <borntraeger@de.ibm.com>
To: Thomas Huth <thuth@redhat.com>,
Janosch Frank <frankja@linux.vnet.ibm.com>
Cc: KVM <kvm@vger.kernel.org>, Cornelia Huck <cohuck@redhat.com>,
David Hildenbrand <david@redhat.com>,
Ulrich Weigand <Ulrich.Weigand@de.ibm.com>,
Claudio Imbrenda <imbrenda@linux.ibm.com>,
Andrea Arcangeli <aarcange@redhat.com>
Subject: Re: [RFCv2 11/37] KVM: s390/mm: Make pages accessible before destroying the guest
Date: Wed, 5 Feb 2020 10:03:01 +0100 [thread overview]
Message-ID: <6b3d7f0a-8cf8-8b2a-370a-ddbc6628941c@de.ibm.com> (raw)
In-Reply-To: <7b73da46-ad64-3ab5-cd59-5a302bbbdc5f@redhat.com>
On 04.02.20 21:52, Thomas Huth wrote:
> On 03/02/2020 14.19, Christian Borntraeger wrote:
>> Before we destroy the secure configuration, we better make all
>> pages accessible again. This also happens during reboot, where we reboot
>> into a non-secure guest that then can go again into a secure mode. As
>> this "new" secure guest will have a new ID we cannot reuse the old page
>> state.
>>
>> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
>> ---
>> arch/s390/include/asm/pgtable.h | 1 +
>> arch/s390/kvm/pv.c | 2 ++
>> arch/s390/mm/gmap.c | 35 +++++++++++++++++++++++++++++++++
>> 3 files changed, 38 insertions(+)
>>
>> diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
>> index 65b6bb47af0a..6e167dcc35f1 100644
>> --- a/arch/s390/include/asm/pgtable.h
>> +++ b/arch/s390/include/asm/pgtable.h
>> @@ -1669,6 +1669,7 @@ extern int vmem_remove_mapping(unsigned long start, unsigned long size);
>> extern int s390_enable_sie(void);
>> extern int s390_enable_skey(void);
>> extern void s390_reset_cmma(struct mm_struct *mm);
>> +extern void s390_reset_acc(struct mm_struct *mm);
>>
>> /* s390 has a private copy of get unmapped area to deal with cache synonyms */
>> #define HAVE_ARCH_UNMAPPED_AREA
>> diff --git a/arch/s390/kvm/pv.c b/arch/s390/kvm/pv.c
>> index a867b9e9c069..24d802072ac7 100644
>> --- a/arch/s390/kvm/pv.c
>> +++ b/arch/s390/kvm/pv.c
>> @@ -66,6 +66,8 @@ int kvm_s390_pv_destroy_vm(struct kvm *kvm)
>> int rc;
>> u32 ret;
>>
>> + /* make all pages accessible before destroying the guest */
>> + s390_reset_acc(kvm->mm);
>> rc = uv_cmd_nodata(kvm_s390_pv_handle(kvm),
>> UVC_CMD_DESTROY_SEC_CONF, &ret);
>> WRITE_ONCE(kvm->arch.gmap->se_handle, 0);
>> diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
>> index bf365a09f900..0b00e8d5fa39 100644
>> --- a/arch/s390/mm/gmap.c
>> +++ b/arch/s390/mm/gmap.c
>> @@ -2648,3 +2648,38 @@ void s390_reset_cmma(struct mm_struct *mm)
>> up_write(&mm->mmap_sem);
>> }
>> EXPORT_SYMBOL_GPL(s390_reset_cmma);
>> +
>> +/*
>> + * make inaccessible pages accessible again
>> + */
>> +static int __s390_reset_acc(pte_t *ptep, unsigned long addr,
>> + unsigned long next, struct mm_walk *walk)
>> +{
>> + pte_t pte = READ_ONCE(*ptep);
>> +
>> + if (pte_present(pte))
>> + uv_convert_from_secure(pte_val(pte) & PAGE_MASK);
>
> Is it ok to ignore the return value from uv_convert_from_secure() ?
> Problems might go unnoticed ... maybe use at least a WARN_ONCE ?
Hmm, it is certainly one of these "should not happen" cases.
So yes, I will add a WARN_ON_ONCE.
>
>> + return 0;
>> +}
>> +
>> +static const struct mm_walk_ops reset_acc_walk_ops = {
>> + .pte_entry = __s390_reset_acc,
>> +};
>> +
>> +#include <linux/sched/mm.h>
>> +void s390_reset_acc(struct mm_struct *mm)
>> +{
>> + /*
>> + * we might be called during
>> + * reset: we walk the pages and clear
>> + * close of all kvm file descriptor: we walk the pages and clear
>> + * exit of process on fd closure: vma already gone, do nothing
>> + */
>> + if (!mmget_not_zero(mm))
>> + return;
>> + down_read(&mm->mmap_sem);
>> + walk_page_range(mm, 0, TASK_SIZE, &reset_acc_walk_ops, NULL);
>> + up_read(&mm->mmap_sem);
>> + mmput(mm);
>> +}
>> +EXPORT_SYMBOL_GPL(s390_reset_acc);
>>
>
> Anyway,
> Reviewed-by: Thomas Huth <thuth@redhat.com>
>
thanks.
next prev parent reply other threads:[~2020-02-05 9:03 UTC|newest]
Thread overview: 200+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-03 13:19 [RFCv2 00/37] KVM: s390: Add support for protected VMs Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 01/37] DOCUMENTATION: protvirt: Protected virtual machine introduction Christian Borntraeger
2020-02-03 15:42 ` Cornelia Huck
2020-02-03 21:41 ` Christian Borntraeger
2020-02-04 9:19 ` Cornelia Huck
2020-02-04 9:32 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 02/37] s390/protvirt: introduce host side setup Christian Borntraeger
2020-02-03 17:12 ` Cornelia Huck
2020-02-03 22:03 ` Christian Borntraeger
2020-02-04 9:28 ` Cornelia Huck
2020-02-04 9:38 ` Christian Borntraeger
2020-02-04 9:49 ` Cornelia Huck
2020-02-04 8:40 ` Thomas Huth
2020-02-04 9:12 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 03/37] s390/protvirt: add ultravisor initialization Christian Borntraeger
2020-02-04 10:03 ` Thomas Huth
2020-02-04 10:23 ` Cornelia Huck
2020-02-04 11:22 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 04/37] mm:gup/writeback: add callbacks for inaccessible pages Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 05/37] s390/mm: provide memory management functions for protected KVM guests Christian Borntraeger
2020-02-04 10:57 ` Cornelia Huck
2020-02-04 11:48 ` Claudio Imbrenda
2020-02-04 11:56 ` Christian Borntraeger
2020-02-04 12:15 ` Cornelia Huck
2020-02-05 9:52 ` Janosch Frank
2020-02-03 13:19 ` [RFCv2 06/37] s390: add (non)secure page access exceptions handlers Christian Borntraeger
2020-02-04 10:37 ` Thomas Huth
2020-02-04 11:41 ` Claudio Imbrenda
2020-02-04 12:48 ` Thomas Huth
2020-02-04 13:08 ` Claudio Imbrenda
2020-02-04 13:22 ` Thomas Huth
2020-02-04 12:03 ` Christian Borntraeger
2020-02-04 11:18 ` Cornelia Huck
2020-02-04 12:04 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 07/37] KVM: s390: add new variants of UV CALL Christian Borntraeger
2020-02-04 12:11 ` Cornelia Huck
2020-02-04 12:30 ` Claudio Imbrenda
2020-02-04 12:34 ` Cornelia Huck
2020-02-04 13:33 ` Christian Borntraeger
2020-02-04 13:27 ` Thomas Huth
2020-02-04 13:55 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 08/37] KVM: s390: protvirt: Add initial lifecycle handling Christian Borntraeger
2020-02-04 12:13 ` David Hildenbrand
2020-02-04 12:34 ` Christian Borntraeger
2020-02-05 10:01 ` Janosch Frank
2020-02-04 16:27 ` Cornelia Huck
2020-02-04 21:13 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 09/37] KVM: s390: protvirt: Add KVM api documentation Christian Borntraeger
2020-02-04 20:19 ` Thomas Huth
2020-02-04 21:40 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 10/37] KVM: s390: protvirt: Secure memory is not mergeable Christian Borntraeger
2020-02-04 12:15 ` David Hildenbrand
2020-02-04 12:53 ` Christian Borntraeger
2020-02-04 12:54 ` David Hildenbrand
2020-02-04 13:04 ` [PATCH v2 " Christian Borntraeger
2020-02-04 13:05 ` David Hildenbrand
2020-02-03 13:19 ` [RFCv2 11/37] KVM: s390/mm: Make pages accessible before destroying the guest Christian Borntraeger
2020-02-04 20:52 ` Thomas Huth
2020-02-05 9:03 ` Christian Borntraeger [this message]
2020-02-05 10:35 ` Cornelia Huck
2020-02-05 18:29 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 12/37] KVM: s390: protvirt: Handle SE notification interceptions Christian Borntraeger
2020-02-04 12:16 ` David Hildenbrand
2020-02-04 12:23 ` Christian Borntraeger
2020-02-04 21:16 ` Thomas Huth
2020-02-04 21:46 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 13/37] KVM: s390: protvirt: Instruction emulation Christian Borntraeger
2020-02-04 12:20 ` David Hildenbrand
2020-02-04 12:29 ` Christian Borntraeger
2020-02-04 17:07 ` Cornelia Huck
2020-02-04 21:21 ` Thomas Huth
2020-02-03 13:19 ` [RFCv2 14/37] KVM: s390: protvirt: Add interruption injection controls Christian Borntraeger
2020-02-05 6:59 ` Thomas Huth
2020-02-05 8:46 ` Christian Borntraeger
2020-02-05 8:56 ` Michael Mueller
2020-02-05 8:54 ` Michael Mueller
2020-02-05 10:45 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 15/37] KVM: s390: protvirt: Implement interruption injection Christian Borntraeger
2020-02-05 9:51 ` Thomas Huth
2020-02-05 10:48 ` Christian Borntraeger
2020-02-05 11:25 ` Cornelia Huck
2020-02-05 17:49 ` Christian Borntraeger
2020-02-06 8:21 ` Cornelia Huck
2020-02-05 17:56 ` Christian Borntraeger
2020-02-05 11:31 ` Cornelia Huck
2020-02-05 11:46 ` Michael Mueller
2020-02-05 12:11 ` Cornelia Huck
2020-02-05 12:26 ` Michael Mueller
2020-02-05 18:00 ` Christian Borntraeger
2020-02-06 8:23 ` Cornelia Huck
2020-02-05 15:30 ` Michael Mueller
2020-02-03 13:19 ` [RFCv2 16/37] KVM: s390: protvirt: Add SCLP interrupt handling Christian Borntraeger
2020-02-05 12:22 ` Cornelia Huck
2020-02-05 18:14 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 17/37] KVM: s390: protvirt: Add machine-check interruption injection controls Christian Borntraeger
2020-02-05 7:06 ` Thomas Huth
2020-02-03 13:19 ` [RFCv2 18/37] KVM: s390: protvirt: Implement machine-check interruption injection Christian Borntraeger
2020-02-05 7:10 ` Thomas Huth
2020-02-05 13:47 ` Cornelia Huck
2020-02-05 18:18 ` Christian Borntraeger
2020-02-06 8:25 ` Cornelia Huck
2020-02-06 9:01 ` Christian Borntraeger
2020-02-06 9:11 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 19/37] KVM: s390: protvirt: Handle spec exception loops Christian Borntraeger
2020-02-05 13:50 ` Cornelia Huck
2020-02-05 18:21 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 20/37] KVM: s390: protvirt: Add new gprs location handling Christian Borntraeger
2020-02-05 11:18 ` Thomas Huth
2020-02-05 18:45 ` Christian Borntraeger
2020-02-05 13:52 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 21/37] KVM: S390: protvirt: Introduce instruction data area bounce buffer Christian Borntraeger
2020-02-05 11:43 ` David Hildenbrand
2020-02-06 8:43 ` Christian Borntraeger
2020-02-05 12:02 ` Thomas Huth
2020-02-05 12:16 ` Janosch Frank
2020-02-05 17:00 ` Thomas Huth
2020-02-06 9:07 ` Christian Borntraeger
2020-02-06 9:18 ` Thomas Huth
2020-02-06 9:21 ` Christian Borntraeger
2020-02-06 9:20 ` Christian Borntraeger
2020-02-06 9:32 ` Janosch Frank
2020-02-06 9:29 ` David Hildenbrand
2020-02-06 9:39 ` [RFCv2.1] " Christian Borntraeger
2020-02-06 9:54 ` David Hildenbrand
2020-02-06 10:02 ` Christian Borntraeger
2020-02-06 10:08 ` David Hildenbrand
2020-02-06 10:10 ` Christian Borntraeger
2020-02-06 12:46 ` Christian Borntraeger
2020-02-06 10:32 ` Thomas Huth
2020-02-06 11:07 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 22/37] KVM: s390: protvirt: handle secure guest prefix pages Christian Borntraeger
2020-02-05 11:51 ` David Hildenbrand
2020-02-05 19:38 ` Christian Borntraeger
2020-02-05 11:52 ` David Hildenbrand
2020-02-05 19:39 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 23/37] KVM: s390/mm: handle guest unpin events Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 24/37] KVM: s390: protvirt: Write sthyi data to instruction data area Christian Borntraeger
2020-02-05 12:09 ` Thomas Huth
2020-02-05 18:52 ` Christian Borntraeger
2020-02-05 14:27 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 25/37] KVM: s390: protvirt: STSI handling Christian Borntraeger
2020-02-05 12:13 ` Thomas Huth
2020-02-05 19:22 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 26/37] KVM: s390: protvirt: disallow one_reg Christian Borntraeger
2020-02-05 12:16 ` Thomas Huth
2020-02-05 19:25 ` Christian Borntraeger
2020-02-05 14:42 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 27/37] KVM: s390: protvirt: Only sync fmt4 registers Christian Borntraeger
2020-02-04 17:15 ` Cornelia Huck
2020-02-04 22:08 ` Christian Borntraeger
2020-02-05 16:29 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 28/37] KVM: s390: protvirt: Add program exception injection Christian Borntraeger
2020-02-05 16:38 ` Cornelia Huck
2020-02-05 19:31 ` Christian Borntraeger
2020-02-05 17:59 ` Thomas Huth
2020-02-05 19:32 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 29/37] DOCUMENTATION: protvirt: Diag 308 IPL Christian Borntraeger
2020-02-03 16:13 ` Cornelia Huck
2020-02-04 8:13 ` Christian Borntraeger
2020-02-04 9:35 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 30/37] KVM: s390: protvirt: Add diag 308 subcode 8 - 10 handling Christian Borntraeger
2020-02-04 18:51 ` Cornelia Huck
2020-02-04 22:19 ` Christian Borntraeger
2020-02-05 18:21 ` Thomas Huth
2020-02-06 10:59 ` Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 31/37] KVM: s390: protvirt: UV calls diag308 0, 1 Christian Borntraeger
2020-02-03 13:19 ` [RFCv2 32/37] KVM: s390: protvirt: Report CPU state to Ultravisor Christian Borntraeger
2020-02-06 11:12 ` Thomas Huth
2020-02-06 11:17 ` Christian Borntraeger
2020-02-06 14:29 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 33/37] KVM: s390: protvirt: Support cmd 5 operation state Christian Borntraeger
2020-02-06 11:21 ` Thomas Huth
2020-02-06 15:17 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 34/37] KVM: s390: protvirt: Add UV debug trace Christian Borntraeger
2020-02-06 9:41 ` Cornelia Huck
2020-02-07 8:05 ` Christian Borntraeger
2020-02-07 8:27 ` Cornelia Huck
2020-02-14 8:32 ` Christian Borntraeger
2020-02-14 8:53 ` Cornelia Huck
2020-02-03 13:19 ` [RFCv2 35/37] KVM: s390: protvirt: Mask PSW interrupt bits for interception 104 and 112 Christian Borntraeger
2020-02-06 10:10 ` Cornelia Huck
2020-02-06 11:11 ` Christian Borntraeger
2020-02-06 12:03 ` Thomas Huth
2020-02-03 13:19 ` [RFCv2 36/37] KVM: s390: protvirt: do not inject interrupts after start Christian Borntraeger
2020-02-06 10:13 ` Cornelia Huck
2020-02-06 14:24 ` Christian Borntraeger
2020-02-06 12:03 ` Thomas Huth
2020-02-03 13:19 ` [RFCv2 37/37] KVM: s390: protvirt: Add UV cpu reset calls Christian Borntraeger
2020-02-05 18:27 ` Thomas Huth
2020-02-05 20:24 ` Christian Borntraeger
2020-02-06 10:45 ` Cornelia Huck
2020-02-06 14:27 ` Christian Borntraeger
2020-02-06 14:39 ` David Hildenbrand
2020-02-06 15:07 ` Thomas Huth
2020-02-03 13:23 ` [RFCv2 00/37] KVM: s390: Add support for protected VMs Cornelia Huck
2020-02-03 13:32 ` Christian Borntraeger
2020-02-03 14:42 ` Cornelia Huck
2020-02-05 11:34 ` David Hildenbrand
2020-02-05 11:38 ` Christian Borntraeger
2020-02-05 11:40 ` Cornelia Huck
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=6b3d7f0a-8cf8-8b2a-370a-ddbc6628941c@de.ibm.com \
--to=borntraeger@de.ibm.com \
--cc=Ulrich.Weigand@de.ibm.com \
--cc=aarcange@redhat.com \
--cc=cohuck@redhat.com \
--cc=david@redhat.com \
--cc=frankja@linux.vnet.ibm.com \
--cc=imbrenda@linux.ibm.com \
--cc=kvm@vger.kernel.org \
--cc=thuth@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).