From 97007500ec3f9b08913ebec986068b9d250a6eed Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Mon, 15 Feb 2016 19:11:58 +0200 Subject: [PATCH] intel_th: sth: Sanitize packet callback's return values According to the stm class interface, the packet callback should return an error if it is asked to generate packets that it doesn't support. When it succeeds, it should return number of bytes consumed from its payload. Currently, for FLAG packet it mistakenly returns 1. This patch addresses these issues. Signed-off-by: Alexander Shishkin Signed-off-by: Greg Kroah-Hartman --- drivers/hwtracing/intel_th/sth.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/hwtracing/intel_th/sth.c b/drivers/hwtracing/intel_th/sth.c index 56101c33e10f..e1aee61dd7b3 100644 --- a/drivers/hwtracing/intel_th/sth.c +++ b/drivers/hwtracing/intel_th/sth.c @@ -94,10 +94,13 @@ static ssize_t sth_stm_packet(struct stm_data *stm_data, unsigned int master, case STP_PACKET_TRIG: if (flags & STP_PACKET_TIMESTAMPED) reg += 4; - iowrite8(*payload, sth->base + reg); + writeb_relaxed(*payload, sth->base + reg); break; case STP_PACKET_MERR: + if (size > 4) + size = 4; + sth_iowrite(&out->MERR, payload, size); break; @@ -107,8 +110,8 @@ static ssize_t sth_stm_packet(struct stm_data *stm_data, unsigned int master, else outp = (u64 __iomem *)&out->FLAG; - size = 1; - sth_iowrite(outp, payload, size); + size = 0; + writeb_relaxed(0, outp); break; case STP_PACKET_USER: @@ -129,6 +132,8 @@ static ssize_t sth_stm_packet(struct stm_data *stm_data, unsigned int master, sth_iowrite(outp, payload, size); break; + default: + return -ENOTSUPP; } return size; -- 2.39.5