From 62dcd9c59f324e484c1d655884e0101a988f6671 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Mon, 23 Nov 2020 11:23:13 +0100 Subject: earlycon: simplify earlycon-table implementation Instead of using the array-of-pointers trick to avoid having gcc mess up the earlycon array stride, specify type alignment when declaring entries to prevent gcc from increasing alignment. This is essentially an alternative (one-line) fix to the problem addressed by commit dd709e72cb93 ("earlycon: Use a pointer table to fix __earlycon_table stride"). gcc can increase the alignment of larger objects with static extent as an optimisation, but this can be suppressed by using the aligned attribute when declaring variables. Note that we have been relying on this behaviour for kernel parameters for 16 years and it indeed hasn't changed since the introduction of the aligned attribute in gcc-3.1. Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20201123102319.8090-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/of/fdt.c | 7 ++----- drivers/tty/serial/earlycon.c | 6 ++---- 2 files changed, 4 insertions(+), 9 deletions(-) (limited to 'drivers') diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 4602e467ca8b..feb0f2d67fc5 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -906,7 +906,7 @@ int __init early_init_dt_scan_chosen_stdout(void) int offset; const char *p, *q, *options = NULL; int l; - const struct earlycon_id **p_match; + const struct earlycon_id *match; const void *fdt = initial_boot_params; offset = fdt_path_offset(fdt, "/chosen"); @@ -933,10 +933,7 @@ int __init early_init_dt_scan_chosen_stdout(void) return 0; } - for (p_match = __earlycon_table; p_match < __earlycon_table_end; - p_match++) { - const struct earlycon_id *match = *p_match; - + for (match = __earlycon_table; match < __earlycon_table_end; match++) { if (!match->compatible[0]) continue; diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c index b70877932d47..57c70851f22a 100644 --- a/drivers/tty/serial/earlycon.c +++ b/drivers/tty/serial/earlycon.c @@ -175,7 +175,7 @@ static int __init register_earlycon(char *buf, const struct earlycon_id *match) */ int __init setup_earlycon(char *buf) { - const struct earlycon_id **p_match; + const struct earlycon_id *match; bool empty_compatible = true; if (!buf || !buf[0]) @@ -185,9 +185,7 @@ int __init setup_earlycon(char *buf) return -EALREADY; again: - for (p_match = __earlycon_table; p_match < __earlycon_table_end; - p_match++) { - const struct earlycon_id *match = *p_match; + for (match = __earlycon_table; match < __earlycon_table_end; match++) { size_t len = strlen(match->name); if (strncmp(buf, match->name, len)) -- cgit v1.2.3