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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: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-purgate-ID: tlsNG-ebf023/1782744396-2D7AE1CC-FAE1CE44/0/0 X-purgate-type: clean X-purgate-size: 2977 On 26.06.2026 17:46, Oleksii Kurochko wrote: > Changes in v4: > - Add an explicit overflow guard in build_guest_isa_str(): return > -ENOSPC when buf is non-NULL and total >= size, to avoid the > size - total underflow being passed to snprintf(). How does ... > @@ -480,6 +489,81 @@ bool riscv_isa_extension_available(const unsigned long *isa_bitmap, > return test_bit(id, isa_bitmap); > } > > +static int build_guest_isa_str(char *buf, size_t size, > + const unsigned long *isa_bitmap) > +{ > + int total; > + > +#if defined(CONFIG_RISCV_32) > + total = snprintf(buf, size, "rv32"); > +#elif defined(CONFIG_RISCV_64) > + total = snprintf(buf, size, "rv64"); > +#else > +# error "Unsupported RISC-V bitness" > +#endif > + > + if ( total < 0 ) > + return total; > + > + if ( buf && ((size_t)total >= size) ) > + return -ENOSPC; ... this help an underflow ... > + for ( unsigned int i = 0; i < ARRAY_SIZE(riscv_isa_ext); i++ ) > + { > + const struct riscv_isa_ext_data *ext = &riscv_isa_ext[i]; > + int ret; > + > + if ( !riscv_isa_extension_available(isa_bitmap, ext->id) ) > + continue; > + > + ret = snprintf(buf ? buf + total : NULL, > + buf ? size - total : 0, "%s%s", ... on any but the first iteration here? > +static void __init init_guest_unsupp(void) > +{ > + __set_bit(RISCV_ISA_EXT_f, guest_unsupp); > + __set_bit(RISCV_ISA_EXT_d, guest_unsupp); > + __set_bit(RISCV_ISA_EXT_q, guest_unsupp); > + __set_bit(RISCV_ISA_EXT_v, guest_unsupp); > + __set_bit(RISCV_ISA_EXT_h, guest_unsupp); > + __set_bit(RISCV_ISA_EXT_sstc, guest_unsupp); > + __set_bit(RISCV_ISA_EXT_svade, guest_unsupp); > + __set_bit(RISCV_ISA_EXT_svpbmt, guest_unsupp); > +} Wouldn't riscv_isa_ext[] better get a prominent reminder that additions there may need mirroring here (unless guest support is implemented at the same time)? (As before, yet better would of course be to make sure this is consistent right from build time, i.e. without the need to have this separate function. Or minimally have the info right in that array, so that while adding one needs to think how to set that separate field.) > --- a/xen/arch/riscv/include/asm/cpufeature.h > +++ b/xen/arch/riscv/include/asm/cpufeature.h > @@ -17,6 +17,7 @@ > */ > #define RISCV_ISA_EXT_BASE 26 > > + > enum riscv_isa_ext_id { > RISCV_ISA_EXT_a, > RISCV_ISA_EXT_c, ??? > @@ -94,6 +95,9 @@ struct arch_domain { > struct p2m_domain p2m; > > struct paging_domain paging; > + > + DECLARE_BITMAP(isa, RISCV_ISA_EXT_MAX); > + char *isa_str; > }; Why is it again that both the bitmap and its string representation need storing? In the end they provide two different sources of truth, as there's no guarantee that they'll remain in sync. Jan