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Revision b5d281f6c16dd432b618bdfd36ddba1a58d5b603 authored by Christian Marangi on 19 June 2022, 22:03:51 UTC, committed by Chanwoo Choi on 29 June 2022, 20:11:17 UTC 
PM / devfreq: Rework freq_table to be local to devfreq struct
 
On a devfreq PROBE_DEFER, the freq_table in the driver profile struct,
is never reset and may be leaved in an undefined state.

This comes from the fact that we store the freq_table in the driver
profile struct that is commonly defined as static and not reset on
PROBE_DEFER.
We currently skip the reinit of the freq_table if we found
it's already defined since a driver may declare his own freq_table.

This logic is flawed in the case devfreq core generate a freq_table, set
it in the profile struct and then PROBE_DEFER, freeing the freq_table.
In this case devfreq will found a NOT NULL freq_table that has been
freed, skip the freq_table generation and probe the driver based on the
wrong table.

To fix this and correctly handle PROBE_DEFER, use a local freq_table and
max_state in the devfreq struct and never modify the freq_table present
in the profile struct if it does provide it.

Fixes: 0ec09ac2cebe ("PM / devfreq: Set the freq_table of devfreq device")
Cc: stable@vger.kernel.org
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
1 parent f44b799
Raw File
ashldi3.c 
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 */

#include <linux/export.h>

#include <linux/libgcc.h>

long long notrace __ashldi3(long long u, word_type b)
{
	DWunion uu, w;
	word_type bm;

	if (b == 0)
		return u;

	uu.ll = u;
	bm = 32 - b;

	if (bm <= 0) {
		w.s.low = 0;
		w.s.high = (unsigned int) uu.s.low << -bm;
	} else {
		const unsigned int carries = (unsigned int) uu.s.low >> bm;

		w.s.low = (unsigned int) uu.s.low << b;
		w.s.high = ((unsigned int) uu.s.high << b) | carries;
	}

	return w.ll;
}
EXPORT_SYMBOL(__ashldi3);
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