diff options
Diffstat (limited to 'meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.14.71-e3000/0054-x86-io-Unroll-string-I-O-when-SEV-is-active.patch')
| -rw-r--r-- | meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.14.71-e3000/0054-x86-io-Unroll-string-I-O-when-SEV-is-active.patch | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.14.71-e3000/0054-x86-io-Unroll-string-I-O-when-SEV-is-active.patch b/meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.14.71-e3000/0054-x86-io-Unroll-string-I-O-when-SEV-is-active.patch new file mode 100644 index 00000000..96d88245 --- /dev/null +++ b/meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.14.71-e3000/0054-x86-io-Unroll-string-I-O-when-SEV-is-active.patch @@ -0,0 +1,124 @@ +From 295d8a0fc04f5f07a892766fc646680c124dc423 Mon Sep 17 00:00:00 2001 +From: Sudheesh Mavila <sudheesh.mavila@amd.com> +Date: Tue, 14 Aug 2018 13:29:25 +0530 +Subject: [PATCH 54/95] x86/io: Unroll string I/O when SEV is active + +From 606b21d4a6498c23632a4693c81b7b24feedd038 +Secure Encrypted Virtualization (SEV) does not support string I/O, so +unroll the string I/O operation into a loop operating on one element at +a time. + +[ tglx: Gave the static key a real name instead of the obscure __sev ] + +Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> +Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> +Signed-off-by: Thomas Gleixner <tglx@linutronix.de> +Reviewed-by: Borislav Petkov <bp@suse.de> +Tested-by: Borislav Petkov <bp@suse.de> +Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> +Cc: Arnd Bergmann <arnd@arndb.de> +Cc: kvm@vger.kernel.org +Cc: David Laight <David.Laight@ACULAB.COM> +Cc: Borislav Petkov <bp@alien8.de> +Link: https://lkml.kernel.org/r/20171020143059.3291-14-brijesh.singh@amd.com + +Signed-off-by: Sudheesh Mavila <sudheesh.mavila@amd.com> +--- + arch/x86/include/asm/io.h | 43 +++++++++++++++++++++++++++++++++++++++---- + arch/x86/mm/mem_encrypt.c | 8 ++++++++ + 2 files changed, 47 insertions(+), 4 deletions(-) + +diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h +index 11398d5..93ae8ae 100644 +--- a/arch/x86/include/asm/io.h ++++ b/arch/x86/include/asm/io.h +@@ -266,6 +266,21 @@ static inline void slow_down_io(void) + + #endif + ++#ifdef CONFIG_AMD_MEM_ENCRYPT ++#include <linux/jump_label.h> ++ ++extern struct static_key_false sev_enable_key; ++static inline bool sev_key_active(void) ++{ ++ return static_branch_unlikely(&sev_enable_key); ++} ++ ++#else /* !CONFIG_AMD_MEM_ENCRYPT */ ++ ++static inline bool sev_key_active(void) { return false; } ++ ++#endif /* CONFIG_AMD_MEM_ENCRYPT */ ++ + #define BUILDIO(bwl, bw, type) \ + static inline void out##bwl(unsigned type value, int port) \ + { \ +@@ -296,14 +311,34 @@ static inline unsigned type in##bwl##_p(int port) \ + \ + static inline void outs##bwl(int port, const void *addr, unsigned long count) \ + { \ +- asm volatile("rep; outs" #bwl \ +- : "+S"(addr), "+c"(count) : "d"(port) : "memory"); \ ++ if (sev_key_active()) { \ ++ unsigned type *value = (unsigned type *)addr; \ ++ while (count) { \ ++ out##bwl(*value, port); \ ++ value++; \ ++ count--; \ ++ } \ ++ } else { \ ++ asm volatile("rep; outs" #bwl \ ++ : "+S"(addr), "+c"(count) \ ++ : "d"(port) : "memory"); \ ++ } \ + } \ + \ + static inline void ins##bwl(int port, void *addr, unsigned long count) \ + { \ +- asm volatile("rep; ins" #bwl \ +- : "+D"(addr), "+c"(count) : "d"(port) : "memory"); \ ++ if (sev_key_active()) { \ ++ unsigned type *value = (unsigned type *)addr; \ ++ while (count) { \ ++ *value = in##bwl(port); \ ++ value++; \ ++ count--; \ ++ } \ ++ } else { \ ++ asm volatile("rep; ins" #bwl \ ++ : "+D"(addr), "+c"(count) \ ++ : "d"(port) : "memory"); \ ++ } \ + } + + BUILDIO(b, b, char) +diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c +index 94fc818..81f50fa 100755 +--- a/arch/x86/mm/mem_encrypt.c ++++ b/arch/x86/mm/mem_encrypt.c +@@ -41,6 +41,8 @@ static char sme_cmdline_off[] __initdata = "off"; + */ + u64 sme_me_mask __section(.data) = 0; + EXPORT_SYMBOL(sme_me_mask); ++DEFINE_STATIC_KEY_FALSE(sev_enable_key); ++EXPORT_SYMBOL_GPL(sev_enable_key); + + static bool sev_enabled __section(.data); + +@@ -313,6 +315,12 @@ void __init mem_encrypt_init(void) + if (sev_active()) + dma_ops = &sev_dma_ops; + ++ /* ++ * With SEV, we need to unroll the rep string I/O instructions. ++ */ ++ if (sev_active()) ++ static_branch_enable(&sev_enable_key); ++ + pr_info("AMD %s active\n", + sev_active() ? "Secure Encrypted Virtualization (SEV)" + : "Secure Memory Encryption (SME)"); +-- +2.7.4 + |