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From: Valery Borovsky <vebohr@gmail.com>
To: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>,
	Arnd Bergmann <arnd@arndb.de>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Benson Leung <bleung@chromium.org>,
	Tzung-Bi Shih <tzungbi@kernel.org>,
	Guenter Roeck <groeck@chromium.org>,
	Miquel Raynal <miquel.raynal@bootlin.com>,
	Richard Weinberger <richard@nod.at>,
	Vignesh Raghavendra <vigneshr@ti.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Linus Walleij <linusw@kernel.org>,
	Randy Dunlap <rdunlap@infradead.org>,
	linux-arm-kernel@lists.infradead.org,
	linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org,
	chrome-platform@lists.linux.dev, linux-mtd@lists.infradead.org,
	Valery Borovsky <vebohr@gmail.com>
Subject: Re: [PATCH 1/5] perf/arm_pmu_acpi: fix reference leak in arm_pmu_acpi_probe error path
Date: Tue,  5 May 2026 13:36:27 +0300	[thread overview]
Message-ID: <inv007-withdrawal-vebohr@gmail.com> (raw)
In-Reply-To: <cover.1777889235.git.vebohr@gmail.com>

Yeah, you're right, my bad. The `arm_pmu_acpi.c` patch is definitely broken.

Since `spe_dev` and `trbe_dev` are statically allocated, they don't have a
`.dev.release` callback. If we hit `platform_device_put()` here, the refcount
drops to zero and triggers `device_release()`, which is going to scream about
the missing release function. At best, we get a messy WARN; at worst, it'll
panic the kernel if someone's running with `panic_on_warn`.

The kernel-doc note about `platform_device_put()` is really meant for dynamic
allocations where the release path actually frees memory. For static setups
like this, the original code is actually the right way to go.

Please drop patches 1/5 through 4/5 from the v1 series—they all suffer from
the same logic error. Patch 5/5 (mfd: sm501) is the only clean one, so I've
re-sent that as a standalone v2.

Sorry for the noise.

Valery Borovsky

WARNING: multiple messages have this Message-ID (diff)
From: Valery Borovsky <vebohr@gmail.com>
To: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>,
	Arnd Bergmann <arnd@arndb.de>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Benson Leung <bleung@chromium.org>,
	Tzung-Bi Shih <tzungbi@kernel.org>,
	Guenter Roeck <groeck@chromium.org>,
	Miquel Raynal <miquel.raynal@bootlin.com>,
	Richard Weinberger <richard@nod.at>,
	Vignesh Raghavendra <vigneshr@ti.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Linus Walleij <linusw@kernel.org>,
	Randy Dunlap <rdunlap@infradead.org>,
	linux-arm-kernel@lists.infradead.org,
	linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org,
	chrome-platform@lists.linux.dev, linux-mtd@lists.infradead.org,
	Valery Borovsky <vebohr@gmail.com>
Subject: Re: [PATCH 1/5] perf/arm_pmu_acpi: fix reference leak in arm_pmu_acpi_probe error path
Date: Tue,  5 May 2026 13:36:27 +0300	[thread overview]
Message-ID: <inv007-withdrawal-vebohr@gmail.com> (raw)
In-Reply-To: <cover.1777889235.git.vebohr@gmail.com>

Yeah, you're right, my bad. The `arm_pmu_acpi.c` patch is definitely broken.

Since `spe_dev` and `trbe_dev` are statically allocated, they don't have a
`.dev.release` callback. If we hit `platform_device_put()` here, the refcount
drops to zero and triggers `device_release()`, which is going to scream about
the missing release function. At best, we get a messy WARN; at worst, it'll
panic the kernel if someone's running with `panic_on_warn`.

The kernel-doc note about `platform_device_put()` is really meant for dynamic
allocations where the release path actually frees memory. For static setups
like this, the original code is actually the right way to go.

Please drop patches 1/5 through 4/5 from the v1 series—they all suffer from
the same logic error. Patch 5/5 (mfd: sm501) is the only clean one, so I've
re-sent that as a standalone v2.

Sorry for the noise.

Valery Borovsky

______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/

  parent reply	other threads:[~2026-05-05 10:36 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <cover.1777889235.git.vebohr@gmail.com>
2026-05-04 10:08 ` [PATCH 1/5] misc: eeprom: digsy_mtc: fix reference leak on failed device registration Vastargazing
2026-05-04 10:08   ` Vastargazing
2026-05-04 10:08 ` [PATCH 2/5] platform/chrome: cros_ec_lpc: " Vastargazing
2026-05-04 10:08   ` Vastargazing
2026-05-05  2:40   ` Tzung-Bi Shih
2026-05-04 10:08 ` [PATCH 3/5] mtd: maps: physmap: " Vastargazing
2026-05-04 10:08   ` Vastargazing
2026-05-04 13:58   ` Miquel Raynal
2026-05-04 13:58     ` Miquel Raynal
2026-05-04 10:08 ` [PATCH 4/5] perf: arm: pmu: " Vastargazing
2026-05-04 10:08   ` Vastargazing
2026-05-04 11:47   ` sashiko-bot
2026-05-05  8:50   ` Sudeep Holla
2026-05-04 10:08 ` [PATCH 5/5] mfd: sm501: " Vastargazing
2026-05-04 10:08   ` Vastargazing
2026-05-04 12:48   ` [PATCH v2] " Valery Borovsky
2026-05-04 13:52     ` Miquel Raynal
2026-05-05 15:00       ` Lee Jones
2026-05-05 15:12         ` Miquel Raynal
2026-05-06 15:40     ` [PATCH v3] " Valery Borovsky
2026-05-14 14:54       ` Lee Jones
2026-05-14 16:26       ` Valery Borovsky
2026-05-05 10:36 ` Valery Borovsky [this message]
2026-05-05 10:36   ` [PATCH 1/5] perf/arm_pmu_acpi: fix reference leak in arm_pmu_acpi_probe error path Valery Borovsky
2026-05-06 15:43 ` [PATCH 3/5] mtd: maps: physmap-core: fix reference leak on failed device registration Valery Borovsky
2026-05-06 15:43   ` Valery Borovsky

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