From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 386C3272908; Tue, 11 Feb 2025 22:57:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739314672; cv=none; b=L9d44DiQePZVDo5SHz1i/E+KW7dZPQfoVx0meR11YInq6zaGST3Y59faqTQqfgHmOl+l1xcnLueihL1qk+eV5K85UCnKhQVlVgJrLFQG1CoMf82ZIrxDE52zPCNnepUIBY/ah/3uxo4mlHx9B4Gi5AV13BcBRcSJM0zjHPiTt+k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739314672; c=relaxed/simple; bh=oUV6Ci2wrXg0RwC2lTlfl6pXAwiSc6nTNV8kazRpBVU=; h=Date:To:From:Subject:Message-Id; b=Ym7cASQQpdam478GHQgrKEJbTuAoRjJNLBglyoqBSpZI4Kj9pP9FnAaYO29nhXCYvy9phgHQzYh4OXZQSoct2a3N8TZfopCxYPqdDC6+sUjuLfo+gdFP9mIKnplSs/xizACEHpXK1SDlwgSqJEdGzAbeRp39tjR4p6fmy1xLamk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=JC1O4tmS; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="JC1O4tmS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 78DDEC4CEDD; Tue, 11 Feb 2025 22:57:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1739314671; bh=oUV6Ci2wrXg0RwC2lTlfl6pXAwiSc6nTNV8kazRpBVU=; h=Date:To:From:Subject:From; b=JC1O4tmS+SO1ttU91Lq5MyeQxDwAkFJs0B4VrRD8iBC47g4VWQlt8GigIwkWAHp33 390a/B4AYwy70R821BfExKe28nS/T4sFP3F8JzMJ4jtinE7PisJbW7hkyAPcT2gVBb yyPQBppfTfK2AJ9oqVM3VNFr6lNRRRNkX7N28A18= Date: Tue, 11 Feb 2025 14:57:50 -0800 To: mm-commits@vger.kernel.org,vincenzo.frascino@arm.com,stable@vger.kernel.org,ryabinin.a.a@gmail.com,rostedt@goodmis.org,npache@redhat.com,glider@google.com,dvyukov@google.com,bigeasy@linutronix.de,andreyknvl@gmail.com,longman@redhat.com,akpm@linux-foundation.org From: Andrew Morton Subject: + kasan-dont-call-find_vm_area-in-rt-kernel.patch added to mm-hotfixes-unstable branch Message-Id: <20250211225751.78DDEC4CEDD@smtp.kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: kasan: don't call find_vm_area() in RT kernel has been added to the -mm mm-hotfixes-unstable branch. Its filename is kasan-dont-call-find_vm_area-in-rt-kernel.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kasan-dont-call-find_vm_area-in-rt-kernel.patch This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Waiman Long Subject: kasan: don't call find_vm_area() in RT kernel Date: Tue, 11 Feb 2025 11:07:50 -0500 The following bug report appeared with a test run in a RT debug kernel. [ 3359.353842] BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 [ 3359.353848] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 140605, name: kunit_try_catch [ 3359.353853] preempt_count: 1, expected: 0 : [ 3359.353933] Call trace: : [ 3359.353955] rt_spin_lock+0x70/0x140 [ 3359.353959] find_vmap_area+0x84/0x168 [ 3359.353963] find_vm_area+0x1c/0x50 [ 3359.353966] print_address_description.constprop.0+0x2a0/0x320 [ 3359.353972] print_report+0x108/0x1f8 [ 3359.353976] kasan_report+0x90/0xc8 [ 3359.353980] __asan_load1+0x60/0x70 print_address_description() is run with a raw_spinlock_t acquired and interrupt disabled. find_vm_area() needs to acquire a spinlock_t which becomes a sleeping lock in the RT kernel. IOW, we can't call find_vm_area() in a RT kernel. Fix this bug report by skipping the find_vm_area() call in this case and just print out the address as is. For !RT kernel, follow the example set in commit 0cce06ba859a ("debugobjects,locking: Annotate debug_object_fill_pool() wait type violation") and use DEFINE_WAIT_OVERRIDE_MAP() to avoid a spinlock_t inside raw_spinlock_t warning. Link: https://lkml.kernel.org/r/20250211160750.1301353-1-longman@redhat.com Fixes: c056a364e954 ("kasan: print virtual mapping info in reports") Signed-off-by: Waiman Long Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Andrey Ryabinin Cc: Dmitriy Vyukov Cc: Steven Rostedt Cc: Mariano Pache Cc: Sebastian Andrzej Siewior Cc: Vincenzo Frascino Cc: Signed-off-by: Andrew Morton --- mm/kasan/report.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) --- a/mm/kasan/report.c~kasan-dont-call-find_vm_area-in-rt-kernel +++ a/mm/kasan/report.c @@ -398,9 +398,20 @@ static void print_address_description(vo pr_err("\n"); } - if (is_vmalloc_addr(addr)) { - struct vm_struct *va = find_vm_area(addr); + if (!is_vmalloc_addr(addr)) + goto print_page; + /* + * RT kernel cannot call find_vm_area() in atomic context. + * For !RT kernel, prevent spinlock_t inside raw_spinlock_t warning + * by raising wait-type to WAIT_SLEEP. + */ + if (!IS_ENABLED(CONFIG_PREEMPT_RT)) { + static DEFINE_WAIT_OVERRIDE_MAP(vmalloc_map, LD_WAIT_SLEEP); + struct vm_struct *va; + + lock_map_acquire_try(&vmalloc_map); + va = find_vm_area(addr); if (va) { pr_err("The buggy address belongs to the virtual mapping at\n" " [%px, %px) created by:\n" @@ -410,8 +421,13 @@ static void print_address_description(vo page = vmalloc_to_page(addr); } + lock_map_release(&vmalloc_map); + } else { + pr_err("The buggy address %px belongs to a vmalloc virtual mapping\n", + addr); } +print_page: if (page) { pr_err("The buggy address belongs to the physical page:\n"); dump_page(page, "kasan: bad access detected"); _ Patches currently in -mm which might be from longman@redhat.com are kasan-dont-call-find_vm_area-in-rt-kernel.patch