The same as the rest of the code, get_ss_info_from_atombios() uses calc_pll_cs->ctx->logger for logging. But calc_pll_cs->ctx is initialized only later in calc_pll_max_vco_construct(). Therefore, any output using DC_LOG_SYNC() leads to a NULL pointer deference in get_ss_info_from_atombios().
According to Sashiko, the very same problem exists in dce112_get_pix_clk_dividers() and dcn3_get_pix_clk_dividers() too. To avoid accessing the NULL context, use clk_src->base.ctx->logger everywhere. That context in base is initialized earlier in dce110_clk_src_construct() and dce112_clk_src_construct(). Before get_ss_info_from_atombios() or Sashiko's get_pix_clk_dividers functions above are actually called. This is done by redefining DC_LOGGER to CTX->logger. Before: dce110_clk_src_construct() did: -> sets clk_src->base.ctx = ctx; -> ss_info_from_atombios_create() -> get_ss_info_from_atombios() <- uses calc_pll_cs->ctx # BOOM -> calc_pll_max_vco_construct() <- sets calc_pll_cs->ctx After: dce110_clk_src_construct() does: -> sets clk_src->base.ctx = ctx; -> ss_info_from_atombios_create() -> get_ss_info_from_atombios() <- uses clk_src->base.ctx Closes: https://bugzilla.suse.com/show_bug.cgi?id=1271175 Closes: https://lore.kernel.org/all/[email protected]/ Fixes: 1296423bf23c ("drm/amd/display: define DC_LOGGER for logger") Signed-off-by: Jiri Slaby (SUSE) <[email protected]> Cc: Lakha, Bhawanpreet <[email protected]> Cc: Harry Wentland <[email protected]> Cc: Leo Li <[email protected]> Cc: Rodrigo Siqueira <[email protected]> Cc: Alex Deucher <[email protected]> Cc: "Christian König" <[email protected]> Cc: David Airlie <[email protected]> Cc: Simona Vetter <[email protected]> Cc: [email protected] --- Cc: [email protected] [v2] Set DC_LOGGER to CTX->logger unconditionally (Bhawanpreet). [v1] https://lore.kernel.org/all/[email protected]/ --- .../drm/amd/display/dc/dce/dce_clock_source.c | 20 +++++++++---------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c b/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c index ecb8493ec523..8e3862f6dac2 100644 --- a/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c +++ b/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c @@ -45,9 +45,7 @@ clk_src->base.ctx #define DC_LOGGER \ - calc_pll_cs->ctx->logger -#define DC_LOGGER_INIT() \ - struct calc_pll_clock_source *calc_pll_cs = &clk_src->calc_pll + CTX->logger #undef FN #define FN(reg_name, field_name) \ @@ -287,6 +285,7 @@ static bool calc_pll_dividers_in_range( } static uint32_t calculate_pixel_clock_pll_dividers( + struct dce110_clk_src *clk_src, struct calc_pll_clock_source *calc_pll_cs, struct pll_settings *pll_settings) { @@ -474,7 +473,7 @@ static uint32_t dce110_get_pix_clk_dividers_helper ( { uint32_t field = 0; uint32_t pll_calc_error = MAX_PLL_CALC_ERROR; - DC_LOGGER_INIT(); + /* Check if reference clock is external (not pcie/xtalin) * HW Dce80 spec: * 00 - PCIE_REFCLK, 01 - XTALIN, 02 - GENERICA, 03 - GENERICB @@ -517,12 +516,14 @@ static uint32_t dce110_get_pix_clk_dividers_helper ( /*Calculate Dividers by HDMI object, no SS case or SS case */ pll_calc_error = calculate_pixel_clock_pll_dividers( + clk_src, &clk_src->calc_pll_hdmi, pll_settings); else /*Calculate Dividers by default object, no SS case or SS case */ pll_calc_error = calculate_pixel_clock_pll_dividers( + clk_src, &clk_src->calc_pll, pll_settings); @@ -568,7 +569,6 @@ static uint32_t dce110_get_pix_clk_dividers( { struct dce110_clk_src *clk_src = TO_DCE110_CLK_SRC(cs); uint32_t pll_calc_error = MAX_PLL_CALC_ERROR; - DC_LOGGER_INIT(); if (pix_clk_params == NULL || pll_settings == NULL || pix_clk_params->requested_pix_clk_100hz == 0) { @@ -600,7 +600,6 @@ static uint32_t dce112_get_pix_clk_dividers( struct pll_settings *pll_settings) { struct dce110_clk_src *clk_src = TO_DCE110_CLK_SRC(cs); - DC_LOGGER_INIT(); if (pix_clk_params == NULL || pll_settings == NULL || pix_clk_params->requested_pix_clk_100hz == 0) { @@ -1442,8 +1441,6 @@ static uint32_t dcn3_get_pix_clk_dividers( unsigned long long actual_pix_clk_100Hz = pix_clk_params ? pix_clk_params->requested_pix_clk_100hz : 0; struct dce110_clk_src *clk_src = TO_DCE110_CLK_SRC(cs); - DC_LOGGER_INIT(); - if (pix_clk_params == NULL || pll_settings == NULL || pix_clk_params->requested_pix_clk_100hz == 0) { DC_LOG_ERROR( @@ -1513,7 +1510,6 @@ static const struct clock_source_funcs dce110_clk_src_funcs = { .get_dp_dto_frequency_100hz = get_dp_dto_frequency_100hz }; - static void get_ss_info_from_atombios( struct dce110_clk_src *clk_src, enum as_signal_type as_signal, @@ -1526,7 +1522,7 @@ static void get_ss_info_from_atombios( struct spread_spectrum_info *ss_info_cur; struct spread_spectrum_data *ss_data_cur; uint32_t i; - DC_LOGGER_INIT(); + if (ss_entries_num == NULL) { DC_LOG_SYNC( "Invalid entry !!!\n"); @@ -1657,6 +1653,7 @@ static void ss_info_from_atombios_create( } static bool calc_pll_max_vco_construct( + struct dce110_clk_src *clk_src, struct calc_pll_clock_source *calc_pll_cs, struct calc_pll_clock_source_init_data *init_data) { @@ -1808,6 +1805,7 @@ bool dce110_clk_src_construct( ss_info_from_atombios_create(clk_src); if (!calc_pll_max_vco_construct( + clk_src, &clk_src->calc_pll, &calc_pll_cs_init_data)) { ASSERT_CRITICAL(false); @@ -1822,7 +1820,7 @@ bool dce110_clk_src_construct( if (!calc_pll_max_vco_construct( - &clk_src->calc_pll_hdmi, &calc_pll_cs_init_data_hdmi)) { + clk_src, &clk_src->calc_pll_hdmi, &calc_pll_cs_init_data_hdmi)) { ASSERT_CRITICAL(false); goto unexpected_failure; } -- 2.55.0
