From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZpA82LN5KGVVW9dFLSWnBdYbkdzlxLgyixMSZA6aGoUriHl0/nUqqmgVUJ0UNYQ9C0JNVvJ ARC-Seal: i=1; a=rsa-sha256; t=1526937896; cv=none; d=google.com; s=arc-20160816; b=v9FeDO2WZl6K5pfioxs71CnyZP2Z7uKg3CkqU7a7BL4mWB1yTbn18r6jeBaK4t7B+j bEi/Aq3aZdWax1IVCJ9qDP1Zf9nCYwyw4fWGQ3M/hZ7BAFi1AIRGSFjo2fqbkrFiuAtW 0OUNMXrWuRmFEfx5b/NutLPzmGmDjpAapDShm/Ah3GQ+exUVwrWof1yKzdWxfqqJTils rWyM5YPYqz59i/xPxyODTCoxvlMoaBsq3q0FM0u5AFpGecX2r5OU+7iu5lWOQqSvsA5e i3ewqKbML+Rm1EGO1GGZxst0tgdXx7yTxyiR+a50M5aEDc71ceaskAczyFK+h6RZCejD IdFQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:dkim-signature:arc-authentication-results; bh=HoKl4VRKR6zQBzNSV2hVjA7vuo6CvBZhC59zsgmNMIs=; b=GA7YAGQeWMlquc6mNvEwY/D4etwpojZzcjC0Mw59F2RzE40QsWxJmXpzABC8lhBlCy MzeXw2x/jOmURsiEytYq5jiVG4Rgx+Ypo8NV8MCLLlo37ZD1eTNDQtBvFc0Rkwhyj2yz r18dwaubvfkdXS0/BKXIsx1Yz8Kkb4LVznG7mSD/49eRP4eokYj8nA0Q03sj+CBh2VGA XXLOO7Ac8IeShxNOGHYAX5fknkj7JYZZgYe9GbWsGsd2EQ6vQaJQleCfkSKsBAPPQewr H/77e9aW+If7d/ueLIhKZcx/EomMxGIbq0S23rgUr17N1e0PcW7Rwu4Y6dZuUy/fmjzc 3x9A== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=ng9xRY+k; spf=pass (google.com: domain of srs0=nia/=ii=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=nia/=II=linuxfoundation.org=gregkh@kernel.org Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=ng9xRY+k; spf=pass (google.com: domain of srs0=nia/=ii=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=nia/=II=linuxfoundation.org=gregkh@kernel.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nicholas Piggin , Michael Ellerman Subject: [PATCH 4.16 033/110] powerpc/powernv: Fix NVRAM sleep in invalid context when crashing Date: Mon, 21 May 2018 23:11:30 +0200 Message-Id: <20180521210506.681631570@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180521210503.823249477@linuxfoundation.org> References: <20180521210503.823249477@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1601109847879759429?= X-GMAIL-MSGID: =?utf-8?q?1601110432225725903?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nicholas Piggin commit c1d2a31397ec51f0370f6bd17b19b39152c263cb upstream. Similarly to opal_event_shutdown, opal_nvram_write can be called in the crash path with irqs disabled. Special case the delay to avoid sleeping in invalid context. Fixes: 3b8070335f75 ("powerpc/powernv: Fix OPAL NVRAM driver OPAL_BUSY loops") Cc: stable@vger.kernel.org # v3.2 Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/platforms/powernv/opal-nvram.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) --- a/arch/powerpc/platforms/powernv/opal-nvram.c +++ b/arch/powerpc/platforms/powernv/opal-nvram.c @@ -44,6 +44,10 @@ static ssize_t opal_nvram_read(char *buf return count; } +/* + * This can be called in the panic path with interrupts off, so use + * mdelay in that case. + */ static ssize_t opal_nvram_write(char *buf, size_t count, loff_t *index) { s64 rc = OPAL_BUSY; @@ -58,10 +62,16 @@ static ssize_t opal_nvram_write(char *bu while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { rc = opal_write_nvram(__pa(buf), count, off); if (rc == OPAL_BUSY_EVENT) { - msleep(OPAL_BUSY_DELAY_MS); + if (in_interrupt() || irqs_disabled()) + mdelay(OPAL_BUSY_DELAY_MS); + else + msleep(OPAL_BUSY_DELAY_MS); opal_poll_events(NULL); } else if (rc == OPAL_BUSY) { - msleep(OPAL_BUSY_DELAY_MS); + if (in_interrupt() || irqs_disabled()) + mdelay(OPAL_BUSY_DELAY_MS); + else + msleep(OPAL_BUSY_DELAY_MS); } }