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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: <30c95ac5-bc1e-4cbd-9a8a-bb1c5ec53922@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-purgate-ID: tlsNG-c1860d/1775569432-F6F4A497-28181E2B/0/0 X-purgate-type: clean X-purgate-size: 2740 On 07.04.2026 12:47, Oleksii Kurochko wrote: > On 4/1/26 3:19 PM, Jan Beulich wrote: >> On 10.03.2026 18:08, Oleksii Kurochko wrote: >>> --- a/xen/arch/riscv/p2m.c >>> +++ b/xen/arch/riscv/p2m.c >>> @@ -45,18 +45,32 @@ struct p2m_pte_ctx { >>> unsigned int level; /* Paging level at which the PTE resides. */ >>> }; >>> >>> -static struct gstage_mode_desc __ro_after_init max_gstage_mode = { >>> - .mode = HGATP_MODE_OFF, >>> - .paging_levels = 0, >>> - .name = "Bare", >>> -}; >>> - >>> /* >>> * Set to the maximum configured support for IPA bits, so the number of IPA bits can be >>> * restricted by external entity (e.g. IOMMU). >>> */ >>> unsigned int __read_mostly p2m_ipa_bits = PADDR_BITS; >>> >>> +static const struct gstage_mode_desc modes[] = { >> >> As a function scope static this was a fine identifier. Please consider whether >> with the wider scope gstage_modes[] might not be better. >> >>> + /* >>> + * Based on the RISC-V spec: >>> + * Bare mode is always supported, regardless of SXLEN. >>> + * When SXLEN=32, the only other valid setting for MODE is Sv32. >>> + * When SXLEN=64, three paged virtual-memory schemes are defined: >>> + * Sv39, Sv48, and Sv57. >>> + */ >>> + [0] = { HGATP_MODE_OFF, 0, "none" }, >>> +#ifdef CONFIG_RISCV_32 >>> + [1] = { HGATP_MODE_SV32X4, 1, "sv32" } >>> +#else >>> + [2] = { HGATP_MODE_SV39X4, 2, "sv39" }, >>> + [3] = { HGATP_MODE_SV48X4, 3, "sv48" }, >>> + [4] = { HGATP_MODE_SV57X4, 4, "sv57" }, >>> +#endif >>> +}; >> >> The dedicated initializer form isn't adding any value here (whereas it slightly >> hampers readability). You really don't want the array to be sparsely populated, >> so perhaps better to leave as it was before? > > I need modes[] to be outside of gstage_mode_detect() as it then could be > re-used. Sure, and I didn't say "where it was before". I said "as it was before", i.e. without dedicated initializers. Jan > For example, if expected G-stage mode should be passed by DTS > property then in DTS property we'll have something like: > chosen { > ... > DOMU1 { > mmu-type="riscv,sv48"; > ... > } > ... > } > > And I will need to have another functions something like: > static unsigned int find_gstage_mode(const char *mmu_type) {...} > which will re-use modes[] to find a correspondent mode and return an > index (or return just correspondent mode) for that mode to then re-use > it to initialize p2m->mode: > p2m->mode = &modes[find_gstage_mode(mmu_type)]; > > ~ Oleksii