From: Claudio Imbrenda <imbrenda@linux.ibm.com>
To: kvm@vger.kernel.org
Cc: borntraeger@de.ibm.com, frankja@linux.ibm.com, thuth@redhat.com,
pasic@linux.ibm.com, david@redhat.com,
linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org,
scgl@linux.ibm.com, mimu@linux.ibm.com, nrb@linux.ibm.com
Subject: [PATCH v10 11/19] s390/mm: KVM: pv: when tearing down, try to destroy protected pages
Date: Thu, 14 Apr 2022 10:03:02 +0200 [thread overview]
Message-ID: <20220414080311.1084834-12-imbrenda@linux.ibm.com> (raw)
In-Reply-To: <20220414080311.1084834-1-imbrenda@linux.ibm.com>
When ptep_get_and_clear_full is called for a mm teardown, we will now
attempt to destroy the secure pages. This will be faster than export.
In case it was not a teardown, or if for some reason the destroy page
UVC failed, we try with an export page, like before.
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
---
arch/s390/include/asm/pgtable.h | 18 +++++++++++++++---
1 file changed, 15 insertions(+), 3 deletions(-)
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 31b7cfb97635..200000f0e1de 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -1164,9 +1164,21 @@ static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
} else {
res = ptep_xchg_lazy(mm, addr, ptep, __pte(_PAGE_INVALID));
}
- /* At this point the reference through the mapping is still present */
- if (mm_is_protected(mm) && pte_present(res))
- uv_convert_owned_from_secure(pte_val(res) & PAGE_MASK);
+ /* Nothing to do */
+ if (!mm_is_protected(mm) || !pte_present(res))
+ return res;
+ /*
+ * At this point the reference through the mapping is still present.
+ * The notifier should have destroyed all protected vCPUs at this
+ * point, so the destroy should be successful.
+ */
+ if (full && !uv_destroy_owned_page(pte_val(res) & PAGE_MASK))
+ return res;
+ /*
+ * But if something went wrong and the pages could not be destroyed,
+ * the slower export is used as fallback instead.
+ */
+ uv_convert_owned_from_secure(pte_val(res) & PAGE_MASK);
return res;
}
--
2.34.1
next prev parent reply other threads:[~2022-04-14 8:04 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-14 8:02 [PATCH v10 00/19] KVM: s390: pv: implement lazy destroy for reboot Claudio Imbrenda
2022-04-14 8:02 ` [PATCH v10 01/19] KVM: s390: pv: leak the topmost page table when destroy fails Claudio Imbrenda
2022-04-14 11:30 ` Janosch Frank
2022-04-14 12:19 ` Claudio Imbrenda
2022-05-05 14:45 ` Thomas Huth
2022-05-06 11:30 ` Claudio Imbrenda
2022-05-16 7:22 ` Nico Boehr
2022-05-16 15:55 ` Claudio Imbrenda
2022-04-14 8:02 ` [PATCH v10 02/19] KVM: s390: pv: handle secure storage violations for protected guests Claudio Imbrenda
2022-05-05 17:10 ` Thomas Huth
2022-05-06 11:33 ` Claudio Imbrenda
2022-04-14 8:02 ` [PATCH v10 03/19] KVM: s390: pv: handle secure storage exceptions for normal guests Claudio Imbrenda
2022-04-14 8:02 ` [PATCH v10 04/19] KVM: s390: pv: refactor s390_reset_acc Claudio Imbrenda
2022-05-16 8:04 ` Nico Boehr
2022-05-16 16:11 ` Claudio Imbrenda
2022-05-30 7:40 ` Nico Boehr
2022-05-30 10:50 ` Claudio Imbrenda
2022-04-14 8:02 ` [PATCH v10 05/19] KVM: s390: pv: usage counter instead of flag Claudio Imbrenda
2022-04-14 8:02 ` [PATCH v10 06/19] KVM: s390: pv: add export before import Claudio Imbrenda
2022-04-14 8:02 ` [PATCH v10 07/19] KVM: s390: pv: module parameter to fence lazy destroy Claudio Imbrenda
2022-04-14 8:02 ` [PATCH v10 08/19] KVM: s390: pv: clear the state without memset Claudio Imbrenda
2022-04-14 8:03 ` [PATCH v10 09/19] KVM: s390: pv: Add kvm_s390_cpus_from_pv to kvm-s390.h and add documentation Claudio Imbrenda
2022-04-14 8:03 ` [PATCH v10 10/19] KVM: s390: pv: add mmu_notifier Claudio Imbrenda
2022-04-14 8:03 ` Claudio Imbrenda [this message]
2022-04-14 8:03 ` [PATCH v10 12/19] KVM: s390: pv: refactoring of kvm_s390_pv_deinit_vm Claudio Imbrenda
2022-04-14 8:03 ` [PATCH v10 13/19] KVM: s390: pv: destroy the configuration before its memory Claudio Imbrenda
2022-05-30 7:37 ` Nico Boehr
2022-05-30 12:05 ` Claudio Imbrenda
2022-04-14 8:03 ` [PATCH v10 14/19] KVM: s390: pv: cleanup leftover protected VMs if needed Claudio Imbrenda
2022-05-30 8:11 ` Nico Boehr
2022-05-30 10:43 ` Claudio Imbrenda
2022-04-14 8:03 ` [PATCH v10 15/19] KVM: s390: pv: asynchronous destroy for reboot Claudio Imbrenda
2022-05-30 9:46 ` Nico Boehr
2022-05-30 11:06 ` Claudio Imbrenda
2022-04-14 8:03 ` [PATCH v10 16/19] KVM: s390: pv: api documentation for asynchronous destroy Claudio Imbrenda
2022-05-30 9:47 ` Nico Boehr
2022-04-14 8:03 ` [PATCH v10 17/19] KVM: s390: pv: add KVM_CAP_S390_PROTECTED_ASYNC_DISABLE Claudio Imbrenda
2022-05-30 10:24 ` Nico Boehr
2022-04-14 8:03 ` [PATCH v10 18/19] KVM: s390: pv: avoid export before import if possible Claudio Imbrenda
2022-05-30 10:07 ` Nico Boehr
2022-05-30 11:16 ` Claudio Imbrenda
2022-04-14 8:03 ` [PATCH v10 19/19] KVM: s390: pv: support for Destroy fast UVC Claudio Imbrenda
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=20220414080311.1084834-12-imbrenda@linux.ibm.com \
--to=imbrenda@linux.ibm.com \
--cc=borntraeger@de.ibm.com \
--cc=david@redhat.com \
--cc=frankja@linux.ibm.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-s390@vger.kernel.org \
--cc=mimu@linux.ibm.com \
--cc=nrb@linux.ibm.com \
--cc=pasic@linux.ibm.com \
--cc=scgl@linux.ibm.com \
--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).