This is a preparatory step in order to do earlier microcode loading on the boot CPU when the domain heap has not been initialized yet and xmalloc still unavailable.
Add make_copy argument which will allow to load microcode directly from the blob bypassing microcode_cache. Signed-off-by: Sergey Dyasli <[email protected]> --- v1 --> v2: - Don't add extra consts --- xen/arch/x86/cpu/microcode/amd.c | 13 +++++++++---- xen/arch/x86/cpu/microcode/core.c | 2 +- xen/arch/x86/cpu/microcode/intel.c | 13 +++++++++---- xen/arch/x86/cpu/microcode/private.h | 15 +++++++++++---- 4 files changed, 30 insertions(+), 13 deletions(-) diff --git a/xen/arch/x86/cpu/microcode/amd.c b/xen/arch/x86/cpu/microcode/amd.c index 8195707ee1..4b097187a0 100644 --- a/xen/arch/x86/cpu/microcode/amd.c +++ b/xen/arch/x86/cpu/microcode/amd.c @@ -300,7 +300,7 @@ static int scan_equiv_cpu_table(const struct container_equiv_table *et) } static struct microcode_patch *cf_check cpu_request_microcode( - const void *buf, size_t size) + const void *buf, size_t size, bool make_copy) { const struct microcode_patch *saved = NULL; struct microcode_patch *patch = NULL; @@ -411,9 +411,14 @@ static struct microcode_patch *cf_check cpu_request_microcode( if ( saved ) { - patch = xmemdup_bytes(saved, saved_size); - if ( !patch ) - error = -ENOMEM; + if ( make_copy ) + { + patch = xmemdup_bytes(saved, saved_size); + if ( !patch ) + error = -ENOMEM; + } + else + patch = (struct microcode_patch *)saved; } if ( error && !patch ) diff --git a/xen/arch/x86/cpu/microcode/core.c b/xen/arch/x86/cpu/microcode/core.c index 452a7ca773..85c05e480d 100644 --- a/xen/arch/x86/cpu/microcode/core.c +++ b/xen/arch/x86/cpu/microcode/core.c @@ -244,7 +244,7 @@ static struct microcode_patch *parse_blob(const char *buf, size_t len) { alternative_vcall(ucode_ops.collect_cpu_info); - return alternative_call(ucode_ops.cpu_request_microcode, buf, len); + return alternative_call(ucode_ops.cpu_request_microcode, buf, len, true); } static void microcode_free_patch(struct microcode_patch *patch) diff --git a/xen/arch/x86/cpu/microcode/intel.c b/xen/arch/x86/cpu/microcode/intel.c index f5ba6d76d7..f7fec4b4ed 100644 --- a/xen/arch/x86/cpu/microcode/intel.c +++ b/xen/arch/x86/cpu/microcode/intel.c @@ -324,7 +324,7 @@ static int cf_check apply_microcode(const struct microcode_patch *patch) } static struct microcode_patch *cf_check cpu_request_microcode( - const void *buf, size_t size) + const void *buf, size_t size, bool make_copy) { int error = 0; const struct microcode_patch *saved = NULL; @@ -364,10 +364,15 @@ static struct microcode_patch *cf_check cpu_request_microcode( if ( saved ) { - patch = xmemdup_bytes(saved, get_totalsize(saved)); + if ( make_copy ) + { + patch = xmemdup_bytes(saved, get_totalsize(saved)); - if ( !patch ) - error = -ENOMEM; + if ( !patch ) + error = -ENOMEM; + } + else + patch = (struct microcode_patch *)saved; } if ( error && !patch ) diff --git a/xen/arch/x86/cpu/microcode/private.h b/xen/arch/x86/cpu/microcode/private.h index c085a10268..58c5dffd7b 100644 --- a/xen/arch/x86/cpu/microcode/private.h +++ b/xen/arch/x86/cpu/microcode/private.h @@ -23,15 +23,22 @@ struct microcode_ops { * older that what is running in the CPU. This is a feature, to better * cope with corner cases from buggy firmware.) * - * If one is found, allocate and return a struct microcode_patch - * encapsulating the appropriate microcode patch. Does not alias the - * original buffer. Must be suitable to be freed with a single xfree(). + * If one is found, behaviour depends on the make_copy argument: + * + * true: allocate and return a struct microcode_patch encapsulating + * the appropriate microcode patch. Does not alias the original + * buffer. Must be suitable to be freed with a single xfree(). + * + * false: return a pointer to the patch within the original buffer. + * This is useful for early microcode loading when xmalloc might + * not be available yet. * * If one is not found, (nothing matches the current CPU), return NULL. * Also may return ERR_PTR(-err), e.g. bad container, out of memory. */ struct microcode_patch *(*cpu_request_microcode)(const void *buf, - size_t size); + size_t size, + bool make_copy); /* * Obtain microcode-relevant details for the current CPU. Results in -- 2.17.1
