From: Sean Christopherson <seanjc@google.com>
To: Ricardo Koller <ricarkol@google.com>
Cc: Oliver Upton <oliver.upton@linux.dev>,
kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu,
andrew.jones@linux.dev, pbonzini@redhat.com, maz@kernel.org,
alexandru.elisei@arm.com, eric.auger@redhat.com,
reijiw@google.com, rananta@google.com, bgardon@google.com,
dmatlack@google.com, axelrasmussen@google.com
Subject: Re: [PATCH v6 09/13] KVM: selftests: aarch64: Add aarch64/page_fault_test
Date: Mon, 19 Sep 2022 20:01:14 +0000 [thread overview]
Message-ID: <YyjKir3OGCfFvAsy@google.com> (raw)
In-Reply-To: <YyjDCWCJ5j8c6T2h@google.com>
On Mon, Sep 19, 2022, Ricardo Koller wrote:
> On Sat, Sep 17, 2022 at 09:58:28PM +0000, Oliver Upton wrote:
> > @@ -536,13 +536,7 @@ static void load_exec_code_for_test(struct kvm_vm *vm)
> > assert(TEST_EXEC_GVA - TEST_GVA);
> > code = hva + 8;
> >
> > - /*
> > - * We need the cast to be separate in order for the compiler to not
> > - * complain with: "‘memcpy’ forming offset [1, 7] is out of the bounds
> > - * [0, 1] of object ‘__exec_test’ with type ‘unsigned char’"
> > - */
> > - c = (uint64_t *)&__exec_test;
> > - memcpy(code, c, 8);
> > + *code = __exec_test;
>
> I remember trying many ways of getting the compiler to not complain, I
> must have tried this (wonder what happened). Anyway, gcc and clang are
> happy with it.
Alternatively, from a code documentation perspective it would be nice to capture
that the size isn't arbitrary. E.g.
typedef uint32_t aarch64_insn_t;
extern aarch64_insn_t __exec_test[2];
{
void *code;
memcpy(code, __exec_test, sizeof(__exec_test));
}
Note, memcpy() is currently dangerous, but hopefully that will be remedied soonish[*]
[*] https://lore.kernel.org/all/20220908233134.3523339-1-seanjc@google.com
next prev parent reply other threads:[~2022-09-19 20:01 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-06 18:09 [PATCH v6 00/13] KVM: selftests: Add aarch64/page_fault_test Ricardo Koller
2022-09-06 18:09 ` [PATCH v6 01/13] KVM: selftests: Add a userfaultfd library Ricardo Koller
2022-09-17 22:14 ` Oliver Upton
2022-09-06 18:09 ` [PATCH v6 02/13] KVM: selftests: aarch64: Add virt_get_pte_hva() library function Ricardo Koller
2022-09-17 22:15 ` Oliver Upton
2022-09-06 18:09 ` [PATCH v6 03/13] KVM: selftests: Add missing close and munmap in __vm_mem_region_delete() Ricardo Koller
2022-09-06 18:09 ` [PATCH v6 04/13] KVM: selftests: aarch64: Construct DEFAULT_MAIR_EL1 using sysreg.h macros Ricardo Koller
2022-09-06 18:09 ` [PATCH v6 05/13] tools: Copy bitfield.h from the kernel sources Ricardo Koller
2022-09-06 18:09 ` [PATCH v6 06/13] KVM: selftests: Stash backing_src_type in struct userspace_mem_region Ricardo Koller
2022-09-17 22:17 ` Oliver Upton
2022-09-06 18:09 ` [PATCH v6 07/13] KVM: selftests: Change ____vm_create() to take struct kvm_vm_mem_params Ricardo Koller
2022-09-19 6:42 ` Andrew Jones
2022-09-19 16:28 ` Sean Christopherson
2022-09-19 19:21 ` Ricardo Koller
2022-09-06 18:09 ` [PATCH v6 08/13] KVM: selftests: Use the right memslot for code, page-tables, and data allocations Ricardo Koller
2022-09-19 6:42 ` Andrew Jones
2022-09-06 18:09 ` [PATCH v6 09/13] KVM: selftests: aarch64: Add aarch64/page_fault_test Ricardo Koller
2022-09-17 21:58 ` Oliver Upton
2022-09-19 19:29 ` Ricardo Koller
2022-09-19 20:01 ` Sean Christopherson [this message]
2022-09-06 18:09 ` [PATCH v6 10/13] KVM: selftests: aarch64: Add userfaultfd tests into page_fault_test Ricardo Koller
2022-09-06 18:09 ` [PATCH v6 11/13] KVM: selftests: aarch64: Add dirty logging " Ricardo Koller
2022-09-06 18:09 ` [PATCH v6 12/13] KVM: selftests: aarch64: Add readonly memslot " Ricardo Koller
2022-09-06 18:09 ` [PATCH v6 13/13] KVM: selftests: aarch64: Add mix of " Ricardo Koller
2022-09-19 10:38 ` [PATCH v6 00/13] KVM: selftests: Add aarch64/page_fault_test Marc Zyngier
2022-09-19 16:38 ` Sean Christopherson
2022-09-19 16:57 ` Marc Zyngier
2022-09-19 18:28 ` Ricardo Koller
2022-09-20 4:14 Ricardo Koller
2022-09-20 4:15 ` [PATCH v6 09/13] KVM: selftests: aarch64: " Ricardo Koller
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