| Message ID | 20250326220304.38dbedcd@gandalf.local.home (mailing list archive) |
|---|---|
| State | Queued |
| Headers | show |
| Series | tracing: Use _text and the kernel offset in last_boot_info | expand |
On Wed, 26 Mar 2025 22:03:04 -0400 Steven Rostedt <rostedt@goodmis.org> wrote: > From: Steven Rostedt <rostedt@goodmis.org> > > Instead of using kaslr_offset() just record the location of "_text". This > makes it possible for user space to use either the System.map or > /proc/kallsyms as what to map all addresses to functions with. > Looks good to me. Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Thank you, > Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> > --- > kernel/trace/trace.c | 18 ++++++------------ > 1 file changed, 6 insertions(+), 12 deletions(-) > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index 85128ef96246..3b8f5e3313e0 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -51,7 +51,7 @@ > #include <linux/workqueue.h> > #include <linux/sort.h> > > -#include <asm/setup.h> /* COMMAND_LINE_SIZE and kaslr_offset() */ > +#include <asm/setup.h> /* COMMAND_LINE_SIZE */ > > #include "trace.h" > #include "trace_output.h" > @@ -5995,7 +5995,7 @@ struct trace_mod_entry { > }; > > struct trace_scratch { > - unsigned long kaslr_addr; > + unsigned long text_addr; > unsigned long nr_entries; > struct trace_mod_entry entries[]; > }; > @@ -6137,11 +6137,7 @@ static void update_last_data(struct trace_array *tr) > kfree_rcu(module_delta, rcu); > > /* Set the persistent ring buffer meta data to this address */ > -#ifdef CONFIG_RANDOMIZE_BASE > - tscratch->kaslr_addr = kaslr_offset(); > -#else > - tscratch->kaslr_addr = 0; > -#endif > + tscratch->text_addr = (unsigned long)_text; > } > > /** > @@ -7000,7 +6996,7 @@ static void show_last_boot_header(struct seq_file *m, struct trace_array *tr) > * should not be the same as the current boot. > */ > if (tscratch && (tr->flags & TRACE_ARRAY_FL_LAST_BOOT)) > - seq_printf(m, "%lx\t[kernel]\n", tscratch->kaslr_addr); > + seq_printf(m, "%lx\t[kernel]\n", tscratch->text_addr); > else > seq_puts(m, "# Current\n"); > } > @@ -9465,10 +9461,8 @@ static void setup_trace_scratch(struct trace_array *tr, > tr->scratch = tscratch; > tr->scratch_size = size; > > -#ifdef CONFIG_RANDOMIZE_BASE > - if (tscratch->kaslr_addr) > - tr->text_delta = kaslr_offset() - tscratch->kaslr_addr; > -#endif > + if (tscratch->text_addr) > + tr->text_delta = (unsigned long)_text - tscratch->text_addr; > > if (struct_size(tscratch, entries, tscratch->nr_entries) > size) > goto reset; > -- > 2.47.2 >
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 85128ef96246..3b8f5e3313e0 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -51,7 +51,7 @@ #include <linux/workqueue.h> #include <linux/sort.h> -#include <asm/setup.h> /* COMMAND_LINE_SIZE and kaslr_offset() */ +#include <asm/setup.h> /* COMMAND_LINE_SIZE */ #include "trace.h" #include "trace_output.h" @@ -5995,7 +5995,7 @@ struct trace_mod_entry { }; struct trace_scratch { - unsigned long kaslr_addr; + unsigned long text_addr; unsigned long nr_entries; struct trace_mod_entry entries[]; }; @@ -6137,11 +6137,7 @@ static void update_last_data(struct trace_array *tr) kfree_rcu(module_delta, rcu); /* Set the persistent ring buffer meta data to this address */ -#ifdef CONFIG_RANDOMIZE_BASE - tscratch->kaslr_addr = kaslr_offset(); -#else - tscratch->kaslr_addr = 0; -#endif + tscratch->text_addr = (unsigned long)_text; } /** @@ -7000,7 +6996,7 @@ static void show_last_boot_header(struct seq_file *m, struct trace_array *tr) * should not be the same as the current boot. */ if (tscratch && (tr->flags & TRACE_ARRAY_FL_LAST_BOOT)) - seq_printf(m, "%lx\t[kernel]\n", tscratch->kaslr_addr); + seq_printf(m, "%lx\t[kernel]\n", tscratch->text_addr); else seq_puts(m, "# Current\n"); } @@ -9465,10 +9461,8 @@ static void setup_trace_scratch(struct trace_array *tr, tr->scratch = tscratch; tr->scratch_size = size; -#ifdef CONFIG_RANDOMIZE_BASE - if (tscratch->kaslr_addr) - tr->text_delta = kaslr_offset() - tscratch->kaslr_addr; -#endif + if (tscratch->text_addr) + tr->text_delta = (unsigned long)_text - tscratch->text_addr; if (struct_size(tscratch, entries, tscratch->nr_entries) > size) goto reset;