On Fri, Mar 05, 2021 at 08:42:06PM +0100, Marco Elver wrote: > Move the no_hash_pointers warning string into __initconst section, so > that it is discarded after init. Remove common start/end characters. > Also remove repeated lines from the array, since the compiler can't > remove duplicate strings for us since the array must appear in > __initconst as defined. > > Note, a similar message appears in kernel/trace/trace.c, but compiling > the feature is guarded by CONFIG_TRACING. It is not immediately obvious > if a space-concious kernel would prefer CONFIG_TRACING=n. Therefore, it > makes sense to keep the message for no_hash_pointers as __initconst, and > not move the NOTICE-printing to a common function.
This seems to have 2-in-1 patch. Care to split? Feel free to add Reviewed-by: Andy Shevchenko <[email protected]> to the __initconst part, but the rest. > Link: > https://lkml.kernel.org/r/camuhmdulkzcjevvjcp7txzldwljsqphe8hqxhnztni9bjt_...@mail.gmail.com > Reported-by: Geert Uytterhoeven <[email protected]> > Signed-off-by: Marco Elver <[email protected]> > --- > lib/vsprintf.c | 30 +++++++++++++++++------------- > 1 file changed, 17 insertions(+), 13 deletions(-) > > diff --git a/lib/vsprintf.c b/lib/vsprintf.c > index 4a14889ccb35..1095689c9c97 100644 > --- a/lib/vsprintf.c > +++ b/lib/vsprintf.c > @@ -2094,26 +2094,30 @@ char *fwnode_string(char *buf, char *end, struct > fwnode_handle *fwnode, > bool no_hash_pointers __ro_after_init; > EXPORT_SYMBOL_GPL(no_hash_pointers); > > +static const char no_hash_pointers_warning[8][55] __initconst = { > + "******************************************************", > + " NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE ", > + " This system shows unhashed kernel memory addresses ", > + " via the console, logs, and other interfaces. This ", > + " might reduce the security of your system. ", > + " If you see this message and you are not debugging ", > + " the kernel, report this immediately to your system ", > + " administrator! ", > +}; > + > static int __init no_hash_pointers_enable(char *str) > { > + /* Indices into no_hash_pointers_warning; -1 is an empty line. */ > + const int lines[] = { 0, 1, -1, 2, 3, 4, -1, 5, 6, 7, -1, 1, 0 }; > + int i; > + > if (no_hash_pointers) > return 0; > > no_hash_pointers = true; > > - pr_warn("**********************************************************\n"); > - pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); > - pr_warn("** **\n"); > - pr_warn("** This system shows unhashed kernel memory addresses **\n"); > - pr_warn("** via the console, logs, and other interfaces. This **\n"); > - pr_warn("** might reduce the security of your system. **\n"); > - pr_warn("** **\n"); > - pr_warn("** If you see this message and you are not debugging **\n"); > - pr_warn("** the kernel, report this immediately to your system **\n"); > - pr_warn("** administrator! **\n"); > - pr_warn("** **\n"); > - pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); > - pr_warn("**********************************************************\n"); > + for (i = 0; i < ARRAY_SIZE(lines); i++) > + pr_warn("**%54s**\n", i == -1 ? "" : > no_hash_pointers_warning[lines[i]]); > > return 0; > } > -- > 2.30.1.766.gb4fecdf3b7-goog > -- With Best Regards, Andy Shevchenko
