From 907516256dd60ed20feaa2a8fd9e2bf148099ec3 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Wed, 15 Mar 2023 12:18:49 +0100 Subject: [PATCH 83/89] xen: get stack address via stack_base array if available Since many years now the stack address of each percpu stack is available via the stack_base[] array (Xen commit 3cb68d2b59ab made it visible). Use that instead of the indirect method via the percpu variables tss_init or tss_page, especially as the layout of tss_page has changed in Xen 4.16 (Xen commit 91d26ed304ff5), resulting in the stack no longer to be found. Signed-off-by: Juergen Gross Signed-off-by: Lianbo Jiang --- xen_hyper.c | 56 ++++++++++++++++++++++++++++++----------------------- 1 file changed, 32 insertions(+), 24 deletions(-) diff --git a/xen_hyper.c b/xen_hyper.c index 1030c0ae25d7..19501de94f4b 100644 --- a/xen_hyper.c +++ b/xen_hyper.c @@ -324,7 +324,7 @@ void xen_hyper_x86_pcpu_init(void) { ulong cpu_info; - ulong init_tss_base, init_tss; + ulong init_tss_base, init_tss, stack_base = 0; ulong sp; struct xen_hyper_pcpu_context *pcc; char *buf, *bp; @@ -340,34 +340,40 @@ xen_hyper_x86_pcpu_init(void) } /* get physical cpu context */ xen_hyper_alloc_pcpu_context_space(XEN_HYPER_MAX_CPUS()); - if (symbol_exists("per_cpu__init_tss")) { + if (symbol_exists("stack_base")) { + stack_base = symbol_value("stack_base"); + flag = 0; + } else if (symbol_exists("per_cpu__init_tss")) { init_tss_base = symbol_value("per_cpu__init_tss"); - flag = TRUE; + flag = 1; } else if (symbol_exists("per_cpu__tss_page")) { - init_tss_base = symbol_value("per_cpu__tss_page"); - flag = TRUE; + init_tss_base = symbol_value("per_cpu__tss_page"); + flag = 1; } else { init_tss_base = symbol_value("init_tss"); - flag = FALSE; + flag = 2; } - buf = GETBUF(XEN_HYPER_SIZE(tss)); + if (flag) + buf = GETBUF(XEN_HYPER_SIZE(tss)); for_cpu_indexes(i, cpuid) { - if (flag) - init_tss = xen_hyper_per_cpu(init_tss_base, cpuid); - else - init_tss = init_tss_base + - XEN_HYPER_SIZE(tss) * cpuid; - if (!readmem(init_tss, KVADDR, buf, - XEN_HYPER_SIZE(tss), "init_tss", RETURN_ON_ERROR)) { - error(FATAL, "cannot read init_tss.\n"); - } - if (machine_type("X86")) { - sp = ULONG(buf + XEN_HYPER_OFFSET(tss_esp0)); - } else if (machine_type("X86_64")) { - sp = ULONG(buf + XEN_HYPER_OFFSET(tss_rsp0)); - } else - sp = 0; + if (flag) { + if (flag == 1) + init_tss = xen_hyper_per_cpu(init_tss_base, cpuid); + else + init_tss = init_tss_base + XEN_HYPER_SIZE(tss) * cpuid; + readmem(init_tss, KVADDR, buf, + XEN_HYPER_SIZE(tss), "init_tss", FAULT_ON_ERROR); + if (machine_type("X86")) { + sp = ULONG(buf + XEN_HYPER_OFFSET(tss_esp0)); + } else if (machine_type("X86_64")) { + sp = ULONG(buf + XEN_HYPER_OFFSET(tss_rsp0)); + } else + sp = 0; + } else { + readmem(stack_base + sizeof(ulong) * cpuid, KVADDR, &sp, + sizeof(ulong), "stack_base", FAULT_ON_ERROR); + } cpu_info = XEN_HYPER_GET_CPU_INFO(sp); if (CRASHDEBUG(1)) { fprintf(fp, "sp=%lx, cpu_info=%lx\n", sp, cpu_info); @@ -377,9 +383,11 @@ xen_hyper_x86_pcpu_init(void) } pcc = &xhpct->context_array[cpuid]; xen_hyper_store_pcpu_context(pcc, cpu_info, bp); - xen_hyper_store_pcpu_context_tss(pcc, init_tss, buf); + if (flag) + xen_hyper_store_pcpu_context_tss(pcc, init_tss, buf); } - FREEBUF(buf); + if (flag) + FREEBUF(buf); } #elif defined(IA64) -- 2.37.1