[Bpf] [PATCH 1/1] bpf, docs: Describe stack contents of function calls

Will Hawkins <hawkinsw@obs.cr> Thu, 06 July 2023 22:20 UTC

From: Will Hawkins <hawkinsw@obs.cr>
To: bpf@vger.kernel.org, bpf@ietf.org
Cc: Will Hawkins <hawkinsw@obs.cr>
Date: Thu, 06 Jul 2023 18:20:20 -0400
Message-Id: <20230706222020.268136-2-hawkinsw@obs.cr>
In-Reply-To: <20230706222020.268136-1-hawkinsw@obs.cr>
References: <20230706222020.268136-1-hawkinsw@obs.cr>
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Subject: [Bpf] [PATCH 1/1] bpf, docs: Describe stack contents of function calls
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The execution of every function proceeds as if it has access to its own
stack space.

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
---
 Documentation/bpf/instruction-set.rst | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Documentation/bpf/instruction-set.rst b/Documentation/bpf/instruction-set.rst
index 751e657973f0..717259767a41 100644
--- a/Documentation/bpf/instruction-set.rst
+++ b/Documentation/bpf/instruction-set.rst
@@ -30,6 +30,11 @@ The eBPF calling convention is defined as:
 R0 - R5 are scratch registers and eBPF programs needs to spill/fill them if
 necessary across calls.
 
+Every function invocation proceeds as if it has exclusive access to an
+implementation-defined amount of stack space. R10 is a pointer to the byte of
+memory with the highest address in that stack space. The contents
+of a function invocation's stack space do not persist between invocations.
+
 Instruction encoding
 ====================
 
-- 
2.40.1

[Bpf] [PATCH 0/1] Describe stack contents for fun… Will Hawkins
[Bpf] [PATCH 1/1] bpf, docs: Describe stack conte… Will Hawkins
Re: [Bpf] [PATCH 1/1] bpf, docs: Describe stack c… Alexei Starovoitov
Re: [Bpf] [PATCH 1/1] bpf, docs: Describe stack c… Will Hawkins
Re: [Bpf] [PATCH 1/1] bpf, docs: Describe stack c… Alexei Starovoitov
Re: [Bpf] [PATCH 1/1] bpf, docs: Describe stack c… Will Hawkins