Hi Jan, On 14/05/2024 16:03, Jan Beulich wrote:
On 13.05.2024 15:40, Elias El Yandouzi wrote:--- a/xen/arch/x86/pv/dom0_build.c +++ b/xen/arch/x86/pv/dom0_build.c @@ -382,6 +382,10 @@ int __init dom0_construct_pv(struct domain *d, l3_pgentry_t *l3tab = NULL, *l3start = NULL; l2_pgentry_t *l2tab = NULL, *l2start = NULL; l1_pgentry_t *l1tab = NULL, *l1start = NULL; + mfn_t l4start_mfn = INVALID_MFN; + mfn_t l3start_mfn = INVALID_MFN; + mfn_t l2start_mfn = INVALID_MFN; + mfn_t l1start_mfn = INVALID_MFN;Just to mention it here again: By limiting the scope of these I'm pretty sure no initializer would be needed even "just in case" (really I don't think they're needed even when the all have function scope, as producer and consumer are always close together afaics; quite different from l<N>start and l<N>tab).
I had a closer look at your suggestion and I don't think it is possible, especially for l3start_mfn.
The variable, l3start_mfn, can get initialized in the else leg of the first if statement along with l3start variable.
If you look a few lines below in the for loop, we call l4e_from_mfn(l3start_mfn, L4_PROT) which assumes l3start_mfn is valid. It could not be the case if we took the first leg of the aforementioned if statement.
I don't think I can this easily limit their scope. It could work for the others, but not l3start_mfn. So I can either leave things as they are or limit the scope of every variables but l3start_mfn.
