From b8bec829c90d45a2d115a52f3a928ce841afc3d4 Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Mon, 4 Feb 2008 22:30:51 -0800 Subject: [PATCH] uml: host TLS diagnostics Add some diagnostics when TLS operations on the host fail. Also spit out more information about the TLS environment on the host at boot time. Signed-off-by: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/sys-i386/tls.c | 30 +++++++++++++++++++++--------- 1 file changed, 21 insertions(+), 9 deletions(-) diff --git a/arch/um/sys-i386/tls.c b/arch/um/sys-i386/tls.c index f29b8a8fc1e0..c6c7131e563b 100644 --- a/arch/um/sys-i386/tls.c +++ b/arch/um/sys-i386/tls.c @@ -26,6 +26,11 @@ int do_set_thread_area(struct user_desc *info) cpu = get_cpu(); ret = os_set_thread_area(info, userspace_pid[cpu]); put_cpu(); + + if (ret) + printk(KERN_ERR "PTRACE_SET_THREAD_AREA failed, err = %d, " + "index = %d\n", ret, info->entry_number); + return ret; } @@ -37,6 +42,11 @@ int do_get_thread_area(struct user_desc *info) cpu = get_cpu(); ret = os_get_thread_area(info, userspace_pid[cpu]); put_cpu(); + + if (ret) + printk(KERN_ERR "PTRACE_GET_THREAD_AREA failed, err = %d, " + "index = %d\n", ret, info->entry_number); + return ret; } @@ -356,10 +366,9 @@ out: return ret; } - /* - * XXX: This part is probably common to i386 and x86-64. Don't create a common - * file for now, do that when implementing x86-64 support. + * This code is really i386-only, but it detects and logs x86_64 GDT indexes + * if a 32-bit UML is running on a 64-bit host. */ static int __init __setup_host_supports_tls(void) { @@ -368,13 +377,16 @@ static int __init __setup_host_supports_tls(void) printk(KERN_INFO "Host TLS support detected\n"); printk(KERN_INFO "Detected host type: "); switch (host_gdt_entry_tls_min) { - case GDT_ENTRY_TLS_MIN_I386: - printk("i386\n"); - break; - case GDT_ENTRY_TLS_MIN_X86_64: - printk("x86_64\n"); - break; + case GDT_ENTRY_TLS_MIN_I386: + printk(KERN_CONT "i386"); + break; + case GDT_ENTRY_TLS_MIN_X86_64: + printk(KERN_CONT "x86_64"); + break; } + printk(KERN_CONT " (GDT indexes %d to %d)\n", + host_gdt_entry_tls_min, + host_gdt_entry_tls_min + GDT_ENTRY_TLS_ENTRIES); } else printk(KERN_ERR " Host TLS support NOT detected! " "TLS support inside UML will not work\n");