diff options
Diffstat (limited to '0027-arm-p2m-Rework-p2m_init.patch')
| -rw-r--r-- | 0027-arm-p2m-Rework-p2m_init.patch | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/0027-arm-p2m-Rework-p2m_init.patch b/0027-arm-p2m-Rework-p2m_init.patch new file mode 100644 index 0000000..0668899 --- /dev/null +++ b/0027-arm-p2m-Rework-p2m_init.patch @@ -0,0 +1,88 @@ +From 86cb37447548420e41ff953a7372972f6154d6d1 Mon Sep 17 00:00:00 2001 +From: Andrew Cooper <andrew.cooper3@citrix.com> +Date: Tue, 25 Oct 2022 09:21:11 +0000 +Subject: [PATCH 27/87] arm/p2m: Rework p2m_init() + +p2m_init() is mostly trivial initialisation, but has two fallible operations +which are on either side of the backpointer trigger for teardown to take +actions. + +p2m_free_vmid() is idempotent with a failed p2m_alloc_vmid(), so rearrange +p2m_init() to perform all trivial setup, then set the backpointer, then +perform all fallible setup. + +This will simplify a future bugfix which needs to add a third fallible +operation. + +No practical change. + +Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> +Reviewed-by: Julien Grall <jgrall@amazon.com> +Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com> +(cherry picked from commit: 3783e583319fa1ce75e414d851f0fde191a14753) +--- + xen/arch/arm/p2m.c | 24 ++++++++++++------------ + 1 file changed, 12 insertions(+), 12 deletions(-) + +diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c +index b2d856a801af..4f7d923ad9f8 100644 +--- a/xen/arch/arm/p2m.c ++++ b/xen/arch/arm/p2m.c +@@ -1730,7 +1730,7 @@ void p2m_final_teardown(struct domain *d) + int p2m_init(struct domain *d) + { + struct p2m_domain *p2m = p2m_get_hostp2m(d); +- int rc = 0; ++ int rc; + unsigned int cpu; + + rwlock_init(&p2m->lock); +@@ -1739,11 +1739,6 @@ int p2m_init(struct domain *d) + INIT_PAGE_LIST_HEAD(&d->arch.paging.p2m_freelist); + + p2m->vmid = INVALID_VMID; +- +- rc = p2m_alloc_vmid(d); +- if ( rc != 0 ) +- return rc; +- + p2m->max_mapped_gfn = _gfn(0); + p2m->lowest_mapped_gfn = _gfn(ULONG_MAX); + +@@ -1759,8 +1754,6 @@ int p2m_init(struct domain *d) + p2m->clean_pte = is_iommu_enabled(d) && + !iommu_has_feature(d, IOMMU_FEAT_COHERENT_WALK); + +- rc = p2m_alloc_table(d); +- + /* + * Make sure that the type chosen to is able to store the an vCPU ID + * between 0 and the maximum of virtual CPUS supported as long as +@@ -1773,13 +1766,20 @@ int p2m_init(struct domain *d) + p2m->last_vcpu_ran[cpu] = INVALID_VCPU_ID; + + /* +- * Besides getting a domain when we only have the p2m in hand, +- * the back pointer to domain is also used in p2m_teardown() +- * as an end-of-initialization indicator. ++ * "Trivial" initialisation is now complete. Set the backpointer so ++ * p2m_teardown() and friends know to do something. + */ + p2m->domain = d; + +- return rc; ++ rc = p2m_alloc_vmid(d); ++ if ( rc ) ++ return rc; ++ ++ rc = p2m_alloc_table(d); ++ if ( rc ) ++ return rc; ++ ++ return 0; + } + + /* +-- +2.37.4 + |