linux-kernel - [PATCH] powerpc/pseries: Remove confusing warning message.

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Message-Id: <20191001132928.72555-1-ldufour@linux.ibm.com>
Date:   Tue,  1 Oct 2019 15:29:28 +0200
From:   Laurent Dufour <ldufour@...ux.ibm.com>
To:     sfr@...ux.ibm.com, mpe@...erman.id.au, benh@...nel.crashing.org,
        paulus@...ba.org, aneesh.kumar@...ux.ibm.com, npiggin@...il.com,
        linuxppc-dev@...ts.ozlabs.org, linux-mm@...ck.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH] powerpc/pseries: Remove confusing warning message.

Since the commit 1211ee61b4a8 ("powerpc/pseries: Read TLB Block Invalidate
Characteristics"), a warning message is displayed when booting a guest on
top of KVM:

lpar: arch/powerpc/platforms/pseries/lpar.c pseries_lpar_read_hblkrm_characteristics Error calling get-system-parameter (0xfffffffd)

This message is displayed because this hypervisor is not supporting the
H_BLOCK_REMOVE hcall and thus is not exposing the corresponding feature.

Reading the TLB Block Invalidate Characteristics should not be done if the
feature is not exposed.

Fixes: 1211ee61b4a8 ("powerpc/pseries: Read TLB Block Invalidate Characteristics")
Reported-by: Stephen Rothwell <sfr@...ux.ibm.com>
Signed-off-by: Laurent Dufour <ldufour@...ux.ibm.com>
---
 arch/powerpc/platforms/pseries/lpar.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c
index b53359258d99..f87a5c64e24d 100644
--- a/arch/powerpc/platforms/pseries/lpar.c
+++ b/arch/powerpc/platforms/pseries/lpar.c
@@ -1419,6 +1419,9 @@ void __init pseries_lpar_read_hblkrm_characteristics(void)
 	unsigned char local_buffer[SPLPAR_TLB_BIC_MAXLENGTH];
 	int call_status, len, idx, bpsize;
 
+	if (!firmware_has_feature(FW_FEATURE_BLOCK_REMOVE))
+		return;
+
 	spin_lock(&rtas_data_buf_lock);
 	memset(rtas_data_buf, 0, RTAS_DATA_BUF_SIZE);
 	call_status = rtas_call(rtas_token("ibm,get-system-parameter"), 3, 1,
-- 
2.23.0