diff options
| author |   Ben Hutchings <bhutchings@solarflare.com> | 2012-10-26 17:53:12 +0100 |
|---|---|---|
| committer | Ben Hutchings <bhutchings@solarflare.com> | 2013-08-21 20:20:39 +0100 |
| commit | 369327fa65f20118571643d673b90d3700166e2d (patch) | |
| tree | 1592dabfa6b61087d09b1ca54340f6c2a94fcb26 /drivers/net | |
| parent | sfc: Add support for MCDI v2 (diff) | |
| download | linux-dev-369327fa65f20118571643d673b90d3700166e2d.tar.xz linux-dev-369327fa65f20118571643d673b90d3700166e2d.zip | |
sfc: Fix race in completion handling
When we poll for MCDI request completion, we don't hold the interface
lock while setting the response fields in struct efx_mcdi_iface.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/ethernet/sfc/mcdi.c | 25 |
1 files changed, 10 insertions, 15 deletions
diff --git a/drivers/net/ethernet/sfc/mcdi.c b/drivers/net/ethernet/sfc/mcdi.c index 2c5ee893feeb..1c8bf81bdc03 100644 --- a/drivers/net/ethernet/sfc/mcdi.c +++ b/drivers/net/ethernet/sfc/mcdi.c @@ -112,16 +112,6 @@ static void efx_mcdi_copyin(struct efx_nic *efx, unsigned cmd, efx->type->mcdi_request(efx, hdr, hdr_len, inbuf, inlen); } -static void -efx_mcdi_copyout(struct efx_nic *efx, efx_dword_t *outbuf, size_t outlen) -{ - struct efx_mcdi_iface *mcdi = efx_mcdi(efx); - - BUG_ON(atomic_read(&mcdi->state) == MCDI_STATE_QUIESCENT); - - efx->type->mcdi_read_response(efx, outbuf, mcdi->resp_hdr_len, outlen); -} - static int efx_mcdi_errno(unsigned int mcdi_err) { switch (mcdi_err) { @@ -200,9 +190,11 @@ static int efx_mcdi_poll(struct efx_nic *efx) /* Check for a reboot atomically with respect to efx_mcdi_copyout() */ rc = efx_mcdi_poll_reboot(efx); if (rc) { + spin_lock_bh(&mcdi->iface_lock); mcdi->resprc = rc; mcdi->resp_hdr_len = 0; mcdi->resp_data_len = 0; + spin_unlock_bh(&mcdi->iface_lock); return 0; } @@ -231,7 +223,9 @@ static int efx_mcdi_poll(struct efx_nic *efx) return -ETIMEDOUT; } + spin_lock_bh(&mcdi->iface_lock); efx_mcdi_read_response_header(efx); + spin_unlock_bh(&mcdi->iface_lock); /* Return rc=0 like wait_event_timeout() */ return 0; @@ -419,7 +413,7 @@ int efx_mcdi_rpc_finish(struct efx_nic *efx, unsigned cmd, size_t inlen, "MC command 0x%x inlen %d mode %d timed out\n", cmd, (int)inlen, mcdi->mode); } else { - size_t resplen; + size_t hdr_len, data_len; /* At the very least we need a memory barrier here to ensure * we pick up changes from efx_mcdi_ev_cpl(). Protect against @@ -427,16 +421,17 @@ int efx_mcdi_rpc_finish(struct efx_nic *efx, unsigned cmd, size_t inlen, * acquiring the iface_lock. */ spin_lock_bh(&mcdi->iface_lock); rc = mcdi->resprc; - resplen = mcdi->resp_data_len; + hdr_len = mcdi->resp_hdr_len; + data_len = mcdi->resp_data_len; spin_unlock_bh(&mcdi->iface_lock); BUG_ON(rc > 0); if (rc == 0) { - efx_mcdi_copyout(efx, outbuf, - min(outlen, mcdi->resp_data_len)); + efx->type->mcdi_read_response(efx, outbuf, hdr_len, + min(outlen, data_len)); if (outlen_actual != NULL) - *outlen_actual = resplen; + *outlen_actual = data_len; } else if (cmd == MC_CMD_REBOOT && rc == -EIO) ; /* Don't reset if MC_CMD_REBOOT returns EIO */ else if (rc == -EIO || rc == -EINTR) { |