3.16.7-ckt2 -stable review patch. If anyone has any objections, please let me know.
------------------ From: Dave Airlie <[email protected]> commit 1c9498425453bb65ef339a57705c5ef59fe1541d upstream. While developing MST support I noticed I often got the wrong data back from a transaction, in a racy fashion. I noticed the scratch space wasn't locked against concurrent users. Based on a patch by Alex, but I've made it a bit more obvious when things are locked. Signed-off-by: Dave Airlie <[email protected]> Signed-off-by: Alex Deucher <[email protected]> Signed-off-by: Luis Henriques <[email protected]> --- drivers/gpu/drm/radeon/atom.c | 11 ++++++++++- drivers/gpu/drm/radeon/atom.h | 2 ++ drivers/gpu/drm/radeon/atombios_dp.c | 4 +++- drivers/gpu/drm/radeon/atombios_i2c.c | 4 +++- drivers/gpu/drm/radeon/radeon_device.c | 1 + 5 files changed, 19 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/radeon/atom.c b/drivers/gpu/drm/radeon/atom.c index 15da7ef344a4..ec1593a6a561 100644 --- a/drivers/gpu/drm/radeon/atom.c +++ b/drivers/gpu/drm/radeon/atom.c @@ -1217,7 +1217,7 @@ free: return ret; } -int atom_execute_table(struct atom_context *ctx, int index, uint32_t * params) +int atom_execute_table_scratch_unlocked(struct atom_context *ctx, int index, uint32_t * params) { int r; @@ -1238,6 +1238,15 @@ int atom_execute_table(struct atom_context *ctx, int index, uint32_t * params) return r; } +int atom_execute_table(struct atom_context *ctx, int index, uint32_t * params) +{ + int r; + mutex_lock(&ctx->scratch_mutex); + r = atom_execute_table_scratch_unlocked(ctx, index, params); + mutex_unlock(&ctx->scratch_mutex); + return r; +} + static int atom_iio_len[] = { 1, 2, 3, 3, 3, 3, 4, 4, 4, 3 }; static void atom_index_iio(struct atom_context *ctx, int base) diff --git a/drivers/gpu/drm/radeon/atom.h b/drivers/gpu/drm/radeon/atom.h index feba6b8d36b3..6d014ddb6b78 100644 --- a/drivers/gpu/drm/radeon/atom.h +++ b/drivers/gpu/drm/radeon/atom.h @@ -125,6 +125,7 @@ struct card_info { struct atom_context { struct card_info *card; struct mutex mutex; + struct mutex scratch_mutex; void *bios; uint32_t cmd_table, data_table; uint16_t *iio; @@ -145,6 +146,7 @@ extern int atom_debug; struct atom_context *atom_parse(struct card_info *, void *); int atom_execute_table(struct atom_context *, int, uint32_t *); +int atom_execute_table_scratch_unlocked(struct atom_context *, int, uint32_t *); int atom_asic_init(struct atom_context *); void atom_destroy(struct atom_context *); bool atom_parse_data_header(struct atom_context *ctx, int index, uint16_t *size, diff --git a/drivers/gpu/drm/radeon/atombios_dp.c b/drivers/gpu/drm/radeon/atombios_dp.c index b1e11f8434e2..67fb65428b1e 100644 --- a/drivers/gpu/drm/radeon/atombios_dp.c +++ b/drivers/gpu/drm/radeon/atombios_dp.c @@ -100,6 +100,7 @@ static int radeon_process_aux_ch(struct radeon_i2c_chan *chan, memset(&args, 0, sizeof(args)); mutex_lock(&chan->mutex); + mutex_lock(&rdev->mode_info.atom_context->scratch_mutex); base = (unsigned char *)(rdev->mode_info.atom_context->scratch + 1); @@ -113,7 +114,7 @@ static int radeon_process_aux_ch(struct radeon_i2c_chan *chan, if (ASIC_IS_DCE4(rdev)) args.v2.ucHPD_ID = chan->rec.hpd; - atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args); + atom_execute_table_scratch_unlocked(rdev->mode_info.atom_context, index, (uint32_t *)&args); *ack = args.v1.ucReplyStatus; @@ -147,6 +148,7 @@ static int radeon_process_aux_ch(struct radeon_i2c_chan *chan, r = recv_bytes; done: + mutex_unlock(&rdev->mode_info.atom_context->scratch_mutex); mutex_unlock(&chan->mutex); return r; diff --git a/drivers/gpu/drm/radeon/atombios_i2c.c b/drivers/gpu/drm/radeon/atombios_i2c.c index 9c570fb15b8c..4157780585a0 100644 --- a/drivers/gpu/drm/radeon/atombios_i2c.c +++ b/drivers/gpu/drm/radeon/atombios_i2c.c @@ -48,6 +48,7 @@ static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan, memset(&args, 0, sizeof(args)); mutex_lock(&chan->mutex); + mutex_lock(&rdev->mode_info.atom_context->scratch_mutex); base = (unsigned char *)rdev->mode_info.atom_context->scratch; @@ -82,7 +83,7 @@ static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan, args.ucSlaveAddr = slave_addr << 1; args.ucLineNumber = chan->rec.i2c_id; - atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args); + atom_execute_table_scratch_unlocked(rdev->mode_info.atom_context, index, (uint32_t *)&args); /* error */ if (args.ucStatus != HW_ASSISTED_I2C_STATUS_SUCCESS) { @@ -95,6 +96,7 @@ static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan, radeon_atom_copy_swap(buf, base, num, false); done: + mutex_unlock(&rdev->mode_info.atom_context->scratch_mutex); mutex_unlock(&chan->mutex); return r; diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c index 52a0cfd0276a..d024389c4272 100644 --- a/drivers/gpu/drm/radeon/radeon_device.c +++ b/drivers/gpu/drm/radeon/radeon_device.c @@ -902,6 +902,7 @@ int radeon_atombios_init(struct radeon_device *rdev) } mutex_init(&rdev->mode_info.atom_context->mutex); + mutex_init(&rdev->mode_info.atom_context->scratch_mutex); radeon_atom_initialize_bios_scratch_regs(rdev->ddev); atom_allocate_fb_scratch(rdev->mode_info.atom_context); return 0; -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
