From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
To: Bjorn Andersson <andersson@kernel.org>
Cc: Konrad Dybcio <konradybcio@kernel.org>,
Mukesh Ojha <quic_mojha@quicinc.com>,
Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
Stephan Gerhold <stephan.gerhold@linaro.org>,
Bartosz Golaszewski <bartosz.golaszewski@linaro.org>,
Kuldeep Singh <quic_kuldsing@quicinc.com>,
Elliot Berman <quic_eberman@quicinc.com>,
Andrew Halaney <ahalaney@redhat.com>,
Avaneesh Kumar Dwivedi <quic_akdwived@quicinc.com>,
Andy Gross <andy.gross@linaro.org>,
linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 3/6] firmware: qcom: scm: Handle various probe ordering for qcom_scm_assign_mem()
Date: Wed, 8 Jan 2025 12:12:51 +0100 [thread overview]
Message-ID: <b0db7570-5606-401f-bf1a-dd1076d2dc52@linaro.org> (raw)
In-Reply-To: <o5oz3scbvsvutv43uqgh74xzfxituzieaa57o6mzomdyr3qixo@2j4ogsbu255o>
On 07/01/2025 01:42, Bjorn Andersson wrote:
>>
>> diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
>> index 5d91b8e22844608f35432f1ba9c08d477d4ff762..93212c8f20ad65ecc44804b00f4b93e3eaaf8d95 100644
>> --- a/drivers/firmware/qcom/qcom_scm.c
>> +++ b/drivers/firmware/qcom/qcom_scm.c
>> @@ -1075,6 +1075,9 @@ int qcom_scm_assign_mem(phys_addr_t mem_addr, size_t mem_sz,
>> int ret, i, b;
>> u64 srcvm_bits = *srcvm;
>>
>> + if (!qcom_scm_is_available())
>> + return -EPROBE_DEFER;
>
> This API is generally called from places other than probe, making the
> return of EPROBE_DEFER undesirable. While not pretty, a client depending
> on the scm driver to be probed is expected to call
> qcom_scm_is_available().
>
> qcom_rmtfs_mem_probe() does this right before calling
> qcom_scm_assign_mem(), am I misunderstanding the case you're describing?
I tried to reproduce my NULL ptr but now I cannot and indeed if every
path is protected with qcom_scm_is_available() everything should be fine.
Let's skip this patch then.
Best regards,
Krzysztof
next prev parent reply other threads:[~2025-01-08 11:12 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-12-09 14:27 [PATCH v2 0/6] firmware: qcom: scm: Fixes for concurrency Krzysztof Kozlowski
2024-12-09 14:27 ` [PATCH v2 1/6] firmware: qcom: scm: Fix missing read barrier in qcom_scm_is_available() Krzysztof Kozlowski
2024-12-09 14:27 ` [PATCH v2 2/6] firmware: qcom: scm: Fix missing read barrier in qcom_scm_get_tzmem_pool() Krzysztof Kozlowski
2024-12-09 14:27 ` [PATCH v2 3/6] firmware: qcom: scm: Handle various probe ordering for qcom_scm_assign_mem() Krzysztof Kozlowski
2024-12-09 20:25 ` Bartosz Golaszewski
2025-01-07 0:42 ` Bjorn Andersson
2025-01-08 11:12 ` Krzysztof Kozlowski [this message]
2024-12-09 14:27 ` [PATCH v2 4/6] firmware: qcom: scm: Cleanup global '__scm' on probe failures Krzysztof Kozlowski
2024-12-09 14:27 ` [PATCH v2 5/6] firmware: qcom: scm: smc: Handle missing SCM device Krzysztof Kozlowski
2024-12-09 15:14 ` Bartosz Golaszewski
2024-12-09 14:27 ` [PATCH v2 6/6] firmware: qcom: scm: smc: Narrow 'mempool' variable scope Krzysztof Kozlowski
2025-01-07 16:38 ` (subset) [PATCH v2 0/6] firmware: qcom: scm: Fixes for concurrency Bjorn Andersson
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