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>>>> int rc; >>>> >>>> - /* >>>> - * enc_payload() calls aesgcm_encrypt(), which can potentially offload to HW. >>>> - * The offload's DMA SG list of data to encrypt has to be in linear mapping. >>>> - */ >>>> - if (!virt_addr_valid(req->req_buf) || !virt_addr_valid(req->resp_buf)) { >>>> - pr_warn("AES-GSM buffers must be in linear mapping"); >>>> - return -EINVAL; >>>> - } >>>> - >>>> guard(mutex)(&snp_cmd_mutex); >>>> >>>> /* Check if the VMPCK is not empty */ >>>> -- >>> >>> This came from: >>> >>> 7ffeb2fc2670 ("x86/sev: Document requirement for linear mapping of >>> guest request buffers") Nah, this is because of db10cb9b574675402b virt: sevguest: Fix passing a stack buffer as a scatterlist target >>> >>> and there was some speculation about the potential of using a crypto >>> accelerator which wants addresses in linear mapping... If the pr_warn() above is removed, then we get this BUG_ON back: === static inline void sg_set_buf(struct scatterlist *sg, const void *buf, unsigned int buflen) { #ifdef CONFIG_DEBUG_SG BUG_ON(!virt_addr_valid(buf)); #endif sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf)); } === So if you really insist on removing my pr_warn(), then post a patch removing the BUG_ON too. Thanks, >>> >> >> Sure, but that speculation was entirely misguided, so we can remove this again. -- Alexey