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keydata= xsDiBFk3nEQRBADAEaSw6zC/EJkiwGPXbWtPxl2xCdSoeepS07jW8UgcHNurfHvUzogEq5xk hu507c3BarVjyWCJOylMNR98Yd8VqD9UfmX0Hb8/BrA+Hl6/DB/eqGptrf4BSRwcZQM32aZK 7Pj2XbGWIUrZrd70x1eAP9QE3P79Y2oLrsCgbZJfEwCgvz9JjGmQqQkRiTVzlZVCJYcyGGsD /0tbFCzD2h20ahe8rC1gbb3K3qk+LpBtvjBu1RY9drYk0NymiGbJWZgab6t1jM7sk2vuf0Py O9Hf9XBmK0uE9IgMaiCpc32XV9oASz6UJebwkX+zF2jG5I1BfnO9g7KlotcA/v5ClMjgo6Gl MDY4HxoSRu3i1cqqSDtVlt+AOVBJBACrZcnHAUSuCXBPy0jOlBhxPqRWv6ND4c9PH1xjQ3NP nxJuMBS8rnNg22uyfAgmBKNLpLgAGVRMZGaGoJObGf72s6TeIqKJo/LtggAS9qAUiuKVnygo 3wjfkS9A3DRO+SpU7JqWdsveeIQyeyEJ/8PTowmSQLakF+3fote9ybzd880fSmFuIEJldWxp Y2ggPGpiZXVsaWNoQHN1c2UuY29tPsJgBBMRAgAgBQJZN5xEAhsDBgsJCAcDAgQVAggDBBYC AwECHgECF4AACgkQoDSui/t3IH4J+wCfQ5jHdEjCRHj23O/5ttg9r9OIruwAn3103WUITZee e7Sbg12UgcQ5lv7SzsFNBFk3nEQQCACCuTjCjFOUdi5Nm244F+78kLghRcin/awv+IrTcIWF hUpSs1Y91iQQ7KItirz5uwCPlwejSJDQJLIS+QtJHaXDXeV6NI0Uef1hP20+y8qydDiVkv6l IreXjTb7DvksRgJNvCkWtYnlS3mYvQ9NzS9PhyALWbXnH6sIJd2O9lKS1Mrfq+y0IXCP10eS FFGg+Av3IQeFatkJAyju0PPthyTqxSI4lZYuJVPknzgaeuJv/2NccrPvmeDg6Coe7ZIeQ8Yj t0ARxu2xytAkkLCel1Lz1WLmwLstV30g80nkgZf/wr+/BXJW/oIvRlonUkxv+IbBM3dX2OV8 AmRv1ySWPTP7AAMFB/9PQK/VtlNUJvg8GXj9ootzrteGfVZVVT4XBJkfwBcpC/XcPzldjv+3 HYudvpdNK3lLujXeA5fLOH+Z/G9WBc5pFVSMocI71I8bT8lIAzreg0WvkWg5V2WZsUMlnDL9 mpwIGFhlbM3gfDMs7MPMu8YQRFVdUvtSpaAs8OFfGQ0ia3LGZcjA6Ik2+xcqscEJzNH+qh8V m5jjp28yZgaqTaRbg3M/+MTbMpicpZuqF4rnB0AQD12/3BNWDR6bmh+EkYSMcEIpQmBM51qM EKYTQGybRCjpnKHGOxG0rfFY1085mBDZCH5Kx0cl0HVJuQKC+dV2ZY5AqjcKwAxpE75MLFkr wkkEGBECAAkFAlk3nEQCGwwACgkQoDSui/t3IH7nnwCfcJWUDUFKdCsBH/E5d+0ZnMQi+G0A nAuWpQkjM1ASeQwSHEeAWPgskBQL In-Reply-To: <1785319678.8631fc262581453bbf619ec5b2062170.19fad586037000e099@vates.tech> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-purgate-ID: tlsNG-d62444/1785859118-1FA6E757-878CAEE4/0/0 X-purgate-type: clean X-purgate-size: 1791 On 29.07.2026 12:05, Teddy Astie wrote: > --- a/xen/drivers/passthrough/vtd/iommu.c > +++ b/xen/drivers/passthrough/vtd/iommu.c > @@ -281,13 +281,13 @@ void free_pgtable_maddr(u64 maddr) > /* context entry handling */ > static u64 bus_to_context_maddr(struct vtd_iommu *iommu, u8 bus) > { > - struct root_entry *root, *root_entries; > + struct root_entry root, *root_entries; > u64 maddr; > > ASSERT(spin_is_locked(&iommu->lock)); > root_entries = (struct root_entry *)map_vtd_domain_page(iommu->root_maddr); > - root = &root_entries[bus]; > - if ( !root_present(*root) ) > + root.val = ACCESS_ONCE(root_entries[bus].val); I'm pretty concerned about this: You're reading only half of the entry here, and you're writing only half of it further down. The other half is reserved right now, but there's not even a comment being added to this effect. (Yet even with a comment, I'd still be concerned, just not as much.) > @@ -295,11 +295,12 @@ static u64 bus_to_context_maddr(struct vtd_iommu *iommu, u8 bus) > unmap_vtd_domain_page(root_entries); > return 0; > } > - set_root_value(*root, maddr); > - set_root_present(*root); > - iommu_sync_cache(root, sizeof(struct root_entry)); > + set_root_value(root, maddr); > + set_root_present(root); > + ACCESS_ONCE(root_entries[bus].val) = root.val; > + iommu_sync_cache(&root_entries[bus], sizeof(struct root_entry)); sizeof() please in favor of sizeof(), whenever possible. > } > - maddr = (u64) get_context_addr(*root); > + maddr = (u64) get_context_addr(root); While there, drop the pointless casts, thus getting rid of two style issues as well? Jan