From git@z Thu Jan 1 00:00:00 1970 Subject: [PATCH] x86/CPU/AMD: avoid printing reset reasons on Xen domU From: Ariadne Conill Date: Thu, 18 Dec 2025 17:01:31 -0800 Message-Id: <20251219010131.12659-1-ariadne@ariadne.space> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Xen domU cannot access the given MMIO address for security reasons, resulting in a failed hypercall in ioremap() due to permissions. Fixes: ab8131028710 ("x86/CPU/AMD: Print the reason for the last reset") Signed-off-by: Ariadne Conill Cc: xen-devel@lists.xenproject.org Cc: stable@vger.kernel.org --- arch/x86/kernel/cpu/amd.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index a6f88ca1a6b4..99308fba4d7d 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -29,6 +29,8 @@ # include #endif +#include + #include "cpu.h" u16 invlpgb_count_max __ro_after_init = 1; @@ -1333,6 +1335,10 @@ static __init int print_s5_reset_status_mmio(void) if (!cpu_feature_enabled(X86_FEATURE_ZEN)) return 0; + /* Xen PV domU cannot access hardware directly, so bail for domU case */ + if (cpu_feature_enabled(X86_FEATURE_XENPV) && !xen_initial_domain()) + return 0; + addr = ioremap(FCH_PM_BASE + FCH_PM_S5_RESET_STATUS, sizeof(value)); if (!addr) return 0; -- 2.51.0